AN PTCA Car Wash vp

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					AN-PTCA001                                                                                                                                        Nematron Pointe Control Application                                                                                                          The Car Wash




                                                                                           AN-PTCA001: The Car Wash
                                                                         1.0 Overview                                                                                                                                                      tional wax application (deluxe option) occurs, fol-
                                                                                                                                                                                                                                           lowed by a final rinse and the hurricane dry.
This application note describes a generic sample
Pointe Controller system application. It illustrates
may basic features including the following.
                                                                                                                                                                                                                                                   2.0 The Basic Control Architecture
   • Tag-name definition                         Control for this application, is provided by a Pointe
   •   Defining local I/O                        Controller (PTC5800), located at station 1. Since
                                                 there is a fair distance between station 1 and station
   •   Use of an ethernet RTU for remote I/O     2, we will save on wiring expenses and improve reli-
   •   Visual Flowchart Editor (VFE) programming ability by using an ethernet RTU (OL4054) for the
                                                 second station's I/O. We also have a small operator
   •   Ladder Logic Programming
                                                 terminal, the OL3420 attached to the Pointe Con-
   •   Local HMI operation                       troller at station 1.
   • Real Time clock operations
                                                         The figure below shows the car wash and the re-
   • Monitor/Debug interface
                                                         lated control components. The I/O resident in the
The basic premise of this application is that it consti-
                                                         Pointe Controller and the Ol4054 is shown as well.
tutes the control system for a two station car wash.
As shown below, the car wash has an initial station
that performs and initial rinse, soaps down the car, The Pointe Control application executes in the
scrubs the wheels, top and sides, then does a sec- Pointe Controller. The Pointe Controller is constant
ondary rinse. A conveyor then pulls the vehicle to commendations with the OL4054
the second station. At the second station, an op-


                                                                               PtC5800                                                                                                 OL4054
                                                 0              1   0                  1   0                  1   0                  1                                                      0              1   0                  1
                              RX                                                                                                                                          RX
                                                 2              3   2                  3   2                  3   2                  3                                                      2              3   2                  3
                                       PtC5800                                                                                                                                     OL4054
                                                 4              5   4                  5   4                  5   4                  5                                                      4              5   4                  5
                              TX                                                                                                                                          TX                6              7   6                  7
                                                 6              7   6                  7   6                  7   6                  7                 RS232
              RS232                              Opti                   Opti                   Opti                   Opti
                                                                                                                                                                                            Opti
                                                                                                                                                                                                   Logic           Opti
                                                                                                                                                                                                                          Logic
                                                        Logic                  Logic                  Logic                  Logic
                                                                                                                                                                                                   10                 10
           Pointe
                                                        10                 10                     10                     10                          Opti
                    Control                             9                  9                      9                      9                                  Logic                                  9                  9
                                                                                                                                                                                                   8                  8
                                                        8                  8                      8                      8
                                                                                                                                                      Ethernet                                     7                  7
              Ethernet                                  7                  7                      7                      7
                                                                                                                                                                         L                         6                  6
                             L                          6                  6                      6                      6
                                                                                                                                                                                                   5                  5
                                                        5                  5                      5                      5                                               R
                             R                                                                                                                                                                     4                  4
                                                        4                  4                      4                      4                                               S
                             S                                                                                                                                                                     3                  3
                                                        3                  3                      3                      3
                                                                                                                                                                         T                         2                  2
                             T                          2                  2                      2                      2                            +       -
             +      -                                                                                                                                                                              1                  1
                                                        1                  1                      1                      1                                          Supplied by
                        Supplied by                                                                                                                                   Class 2
                          Class 2                                                                                                                                   Circuit Only
                        Circuit Only                                                                                                                                8-30 VDC
                        8-30 VDC




           Input                                                                                         Output                                     Input                                                                             Output
           0 Car Sense 1                                                                                 0 Spray 1                                  0 Car Sense 2                                                                     0 Spray 2
           1 Wheel Sense                                                                                 1 Soaper                                   1 Dry Sensor                                                                      1 Conveyor Motor
           2                                                                                             2 Top Brush                                2 Conveyer Fault                                                                  2 Blower
           3                                                                                             3 Side Brush                               3                                                                                 3 Waxer                   Hurricane dryer
           4                                                                                             4 Wheel Scubber                            4                                                                                 4
           5                                                                                             5 Wheel Scrub Insert                       5                                                                                 5
           6                                                                                             6                                          6                                                                                 6
                                                                                                                                                                                                                                                    Final rinse
           7                                                                                             7                                          7                                                                                 7

                                                                                                                                                                                                                                                                                   Dry
                                                                                                                                                                                                                                                                                   Sensor
                                                                                                OL3420
                                                                                                                                                                                   Top Brush

                                                     Pull to car sensor 1
                                                           WAITING!
                                 OM


                                       Start                            Delux
                                                                                                                                                                                                                                                                              }
                                                                                                                                                                                                                                                                              }
                                                                                                                                                                                                                                                                              }

                                                                                                                                         Wheel
                                                                                                                                         Sensor                                                                                                                Side Brush                   Station #2
                                                                                                                                                                                                                                                  }
                                                                                                                                                                                                                                                  }
                                                                                                                                                                                                                                                  }


                                                                                                                                                   Wheel Scrubber                                                                                                     Station #1




                                                                                                                                                                                                                                                                                                         1
AN-PTCA001                         Nematron Pointe Controller Application                         The Car Wash



                                                           3.3 Memory Tags
           3.0 Defining Tag Names                          Memory tags is where we keep internal data and
From our system layout and our knowledge of the            status information.
basic sequence of operations we want our car wash
to perform, we can define most of the tag names            The bits tags indicate yes/no status information. We
that we will need. In the actual development pro-          will need a flag to indicate whether or not we are
cess, you'll define the known tags - then add              doing a deluxe wash, when each station is complete
additional tags as they become necessary. Here,            and when the conveyor should be enabled. In addi-
we'll just go through all of the tags that are required    tion, since we want to update our time information
to control our car wash.                                   on the display once per second, we need a flag to in-
                                                           dicate that it is time to update the display. Those
3.1 Input Tags                                             tag-name definitions are shown below.
The input bits, are all either I/O inputs, or bits asso-
ciated with the operator panel. To enter them, ex-
pand the Memory tree on the left side of the editor
and double click on "Inputs, %IX (Bits)". the correct
entries are shown below.




                                                           We also will need a number of 8 bit unsigned, 32 bit
                                                           unsigned and 32 bit signed variables.

                                                           We use 8-bit as step counters. In the wash se-
                                                           quence, these step counters are used to keep track
3.2 Output Tags                                            of the active process step(s).
For this application, all output tags are bit tags asso-
ciated with digital outputs or operator panel func-
tions.




                                                                                                              2
AN-PTCA001                      Nematron Pointe Controller Application                     The Car Wash



The only 32 bit unsigned variable we need in this 3.5 Timers
application is a tag for the number of seconds re-
                                                   Lastly, one timer is needed, in this application, to
maining in the process step. This tag simply holds
                                                   time the various processes. It is shown below.
the seconds remaining value temporarily, before
the value is inserted into the display line.




We need three 32 bit signed tag-names to hold data
pertaining to the real-time clock, as shown below.          4.0 Defining the I/O Hardware
                                                     This demo application will use one OL2201 digital
                                                     input simulator module and one OL2108 relay
                                                     output module, in addition to the OL3420 operator
                                                     terminal, in the Pointe Controller. We'll use an
                                                     OL2201 digital input simulator and an OL2109
                                                     transistor output module in the RTU.

                                                       Note : The only reason the OL2108 is used one
                                                       place and an OL2109 the other is to provide an
                                                       example of both.

                                                    To define the I/O, select "Configure I/O" from the
3.4 String Tag-names                                "Project" drop down list. In the slots, where the I/O
Anytime we deal with a display that has alphanu- modules are to be placed, select the appropriate
meric capability, we need string tag-names. The modules by clicking the arrow, then selecting the
first two tag-names listed below (line1 and line2) module type, as shown below.
are the names that we will use when writing text to
the two display lines. The timeStamp tag is used to
hold the time read from the real-time clock (it is
read as a long string). The other tags are strings
used to make up time messages for the display.




                                                                                                        3
AN-PTCA001                      Nematron Pointe Controller Application                  The Car Wash



After selecting the appropriate I/O modules for the
Pointe Controller, associate tag-names with the
physical I/O, as shown in the following series of
screens.




                                                      Now do the same for the RTU, as shown.




                                                                                                  4
AN-PTCA001                       Nematron Pointe Controller Application   The Car Wash




        5.0 The application program
A very powerful feature of the Pointe Controller is
the ability to break your application program up
into logical segments. Breaking the program into
separate flow or ladder charts that each are associ-
ated with an identifiable device, or process, simpli-
fies the software, makes documentation, editing
and development much easier and clearer, and re-
sults in better programs.

The program, for this application consists of three
flow charts and one ladder chart. The charts, and a
brief functional summary of each is given below.
   • CarWash : This is the overall supervisory
     flow chart for the entire car wash. It waits
     for the operator to press the START button,
     then provides high level supervision of the
     overall car wash sequence. It passes off di-
     rect control to the other flow charts to han-
     dle the de tailed func tion al ity of each
     station.
   • StationOne : This flow chart is enabled by
     the CarWash chart. It handles the sequence
     of operations at the first station.
   • ConveyorControl : This ladder chart handles
     the use of the car conveyor to transfer the
     car from station 1 to station 2. It is enabled
     by the CarWash chart and passes control
     back when it is complete.
   • StationTwo : This flow chart is enabled by the
     CarWash chart. It handles the sequence of
     operations at the second station. It hands
     control back to CarWash when complete.


This program is downloadable from either the
Nematron web site (www.nematron.com) or the
Optimation web site (www.optimate.com).




                                                                                    5
AN-PTCA001                         Nematron Pointe Controller Application                                         The Car Wash



5.1 The CarWash Flow Chart
The CarWash flow chart is shown on
                                               CarWash
the right, and continued on the next
page.
                                             Read real time

The first levels of blocks take care of
some system houskeeping. The real
                                                   If            oldSeconds =
time clock is read on every pass, and         one second then         seconds
its data parsed into the appropriate             tick            update_display =
                                                    ?                TRUE
tags. Every time the second's value                 else
changes, the "update_display flag is
set. This flag is used later to handle the
                                                                 Turn off wash
updating of the display, for timed oper-     wash state=0 then
                                                                 active LED
                                                                 Clear conveyor
ation count downs.                                 ?             Enabled

                                                    else
Before the operator preses the start
button, the system is in wash state 0. In                                if              set up “seconds to
this state, the time of day (Greenwich                             update_display then   go” string”
                                                                      = true             (used throughout
Mean Time), date, etc. is displayed on                                   ?               program)
the operator panel's top line, updating                                   else

once per sec ond. If the sen sor                                                          display time &
                                                                                          date on top line
indicotors (the toggle switches on the
two OL2201 modules) have been
cleared (all flipped to the right), the
                                                                                                  if
bottom line of the display will be given                                                    all sensors    then
a message reading "Push START when                                                           cleared
                                                                                                  ?
ready. If not, it will be given the mes-                                                          else
sage "Clear all switches".
                                                                                         Place “Clear all         Place “Push START
                                                                                         switches” prompt         when ready”
When the operator presses the start                                                      on bottom line           on bottom line
button, the wash state will be changed
to 1, causing the program to move to
the next area of the flow chart.                                         if
                                                                    START button then     Set wash state
                                                                      pressed                  =1
When we get to wash state 1, the flow                                    ?
                                                                              else
chart turns on and starts the LED, inset
in the START button ON, but not flash-
ing. It will then put the message "Pull           if              Turn ON washing
                                             wash state=1 then    lite and turn its
car to sensor 1" on the top line of the            ?              flash OFF
display and "WAITING" on the bottom
                                                    else
line.
                                                                 Display “Pull to
                                                                  car sensor 1”
                                                                 Display “WAITING”
The flow chart then waits for the Car 1                          on 2nd line
sensor switch to be moved to the left,
indicating that your car is at the first
                                                                         if              wash state = 2
station. When it sees this sensor acti-                             car Sense 1 then
vated, it will change the wash state tag                                = ON             station 1 step = 0
                                                                         ?
to 2.                                                                         else


                                               continue on
                                               next page




                                                                                                                                  6
AN-PTCA001                       Nematron Pointe Controller Application                               The Car Wash



In wash state 2, the actual sequence of
op er a tions is handed off to the
StationOne flow chart. This chart sim-               if
                                                                      washing flash
                                                wash state=2 then
ply turns ON the washing LED's flash-                ?
                                                                       = ON
ing operation.
                                                      else

When the StationOne flow chart com-
pletes, it will set the wash state to 3.            if
                                                            then    turn ON conveyor
Wash state 3 is han dled by the                wash state=3
                                                                    enable
                                                    ?
ConveyorControl ladder logic chart.
When it com pletes successfully,                      else
ConveyorControl will set the wash
state to 4. If the conveyor jams, wash
                                                     if
state will be set to 7.                         wash state=4
                                                             then   turn OFF conveyor
                                                                    enable
                                                     ?
Wash state four is the wash station 2                 else
operations, which is handled by the
StationTwo flow chart. When it com-
pletes, it will set the wash state to 5.            if               turn OFF washing
                                               wash state=5 then     flash
                                                                     turn OFF delux
                                                    ?                light
In wash state 5, the washing flash and
                                                      else
delux lights are turned OFF to indicate
that the active wash operation is com-                              display “Pull out of
                                                                    wash bay” and
plete. A prompt - "Pull out of wash bay"                            “WAITING!”
is placed on the display until the car
sensor 2 is deactivated. When sensor
2 is off, indicating that the car has
                                                                             if
moved out of the second wash station,                                  car sense 2    then
                                                                                             wash state = 6
wash state is set to 6.                                                   = OFF
                                                                              ?
                                                                              else
In wash state 6, our wash operation is
complete. Our very polite controller
displays "Thank you", "Come Again!"                 if               display
                                               wash state=6 then     “Thank you.”
for three seconds, then sets the wash               ?                “Come Again!”
state to 0. We're now ready to start
again with the next car.                              else

                                                                     wait 3 seconds
Wash state 7 is reached only if there is
a conveyor jam. Once it is manually
cleared & the jam sensor is OFF, the                                 wash state = 0

wash state is set to 5.

As you can see, the real "meat" of the              if
                                                            then
                                                                    display
                                               wash state=7         “Conveyor jammed”
wash con trol take s place in                       ?               “Please clear it!”
Stat ionOne, St ationTwo and
ConveyorControl. The flow chart ties it                else

all together.                                                              if
                                                                       conveyor
                                                                                      then
                                                                       jammed                wash state = 5
                                                                        = FALSE
                                                                            ?
                                                                               else


                                                   Return




                                                                                                                7
AN-PTCA001                         Nematron Pointe Controller Application                                              The Car Wash



5.2 The StationOne Flow Chart                   StationOne

The StationOne flow chart is shown
on the right and continued on the
next page.                                           if                      if               set process timer
                                               wash state=2 then       station 1 step then    for 20 seconds
                                                      ?                    =0                 set step 1
                                                                             ?
The StationOne flow chart waits for                    else                   else
the overall wash state to be wash
state 2. In wash state 2, this flow
chart takes over control.                                                    if
                                                                       station 1 step then    Turn spray_1 ON
                                                                           =1
                                                                             ?
The first thing it does is spray the car                                      else
for 20 seconds. Step 0 starts the
                                                                                                     if              display “Initial
timer & step 1 performs the spray un-                                                          update_display then   Rinse” & number of
                                                                                                 = TRUE              seconds remaining
til the process timer times out. While                                                               ?
spraying the operator panel will dis-                                                                  else
play "Initial Rinse" and count down
the time remaining.                                                                                 if
                                                                                               process time then     station1_step = 2
                                                                                                 complete
When the process timer is sensed as                                                                  ?
complete, in step 1, the flow chart                                                                    else          set process timer
                                                                                                                     for 18 seconds
sets the station_1 step to 2 and starts
the process timer.
                                                                             if
In step 2, the spray is turned offand                                  station 1 step then   Turn spray_1 OFF
                                                                           =2                Turn soaper ON
soap is applied. The operator panel                                          ?
informs the operator that the car                                             else
wash is applying soap along with the                                                                 if              display “Applying
time remaining. Step 2's flow logic                                                            update_display then   the soap” &
                                                                                                 = TRUE              number of
continues to check the process timer                                                                 ?               seconds remaining

until it times out. When it times out,                                                                 else

the station1_step is advanced to 3.
                                                                                                    if
                                                                                               process time then     station1_step = 3
Step 3 turns off the soaper and out-                                                             complete
puts the signal for the wheel scrub-                                                                 ?

bers to insert. The operator panel                                                                     else          stop process timer

displays a message indicating that
the wheel scrubbers are being in-
                                                                                             Turn soaper OFF
serted and the program is waiting for                                        if
                                                                       station 1 step then   Turn wheel scrubber
the sensor that indicates they are in-                                     =3                insert ON

serted. Once the wheel scrubber                                              ?
                                                                              else
sensor input indicates that the wheel      continues to Return block
                                                                                                     if              display “Wheel
scrubbers are fully inserted, sta-                                                             update_display then   scrubbers IN” and
tion_1 step is advanced to 4 and the                                                             = TRUE              “Switch ON when IN”
                                                                                                     ?
process timer is started.                                                                              else



                                                                                                     if
                                                                                                wheel sense then     station1_step = 4
                                                                                                 = TRUE
                                                                                                      ?
                                                                                                       else          set process timer
                                                                                                                     for 17 seconds



                                                                continued on next page




                                                                                                                                           8
AN-PTCA001                          Nematron Pointe Controller Application                            The Car Wash



By the time the program flow reaches
step 4, the wheel scrubbers have been
verified as fully inserted. Step 4 han-                 if
                                                  station 1 step then    Turn wheel
dles the scrubbing of the wheels.                                        scrubbers ON
                                                      =4
While the wheels are being scrubbed,                    ?
the operator panel will display "Scrub-                  else
bing the wheels" and indicate the
                                                                                if              display “Scrubbing
number of seconds remaining. Once                                         update_display then   the wheels” & number
the process time has completed, the                                         = TRUE              of seconds remaining
                                                                                ?
flow chart will advance the station1
step to 5.                                                                       else



In step 5, the wheel scrubbers are                                             if
turned off and extracted. The operator                                    process time then     station1_step = 5
                                                                            complete
panel informs the operator that the
                                                                                ?
wheel scrubbers are moving out and it                                                           stop process timer
                                                                                 else
is waiting for the wheel scrubber insert
switch to be turned off to verify that
they are out of the way. Once the
wheel scrubbers are verified as re-                     if
                                                  station 1 step then   Turn insert OFF
tracted, the station1step number is ad-
                                                      =5                Turn scrubbers OFF
vanced to 6 and the process timer
                                                        ?
started for the next operation.                          else
                                                                        display “Wheel
                                                                        scrubbers OUT” &
In station 's sixth step, the car is scrub-                             “Switch OFF when
                                                                        out”
ber side and top with brushes. [Since
this is a high quality car wash, the
brushes are very soft, and will not
                                                                               if
scratch the paint.] Again, the opera-                                     wheel insert then
tor is informed of the action that is                                                           station1_step = 6
                                                                          sense=FALSE
occuring and the time remaining, via                                            ?
the operoator panel's alphanumeric                                               else           set process timer
display.                                                                                        to 22 seconds


When the bush step completes, the
flow chart advances the step count to 7                 if              Turn top and side
and starts the timer for the next pro-            station 1 step then   brushes ON
cess.                                                 =6
                                                        ?
                                                         else

                                                                                if              display “Top & Side
                                                                          update_display then   brushes” and
                                                                            = TRUE              time remaining
                                                                                ?
                                                                                 else



                                                                                if
                                                                           process time then    station1_step = 7
                                                                            complete
                                                                                 ?
                                                                                 else           set process timer
                                                                                                for 20 seconds



                                              continued on next page




                                                                                                                       9
AN-PTCA001                        Nematron Pointe Controller Application                                   The Car Wash



The final step of station one's flow
chart handles the second rinse. The                         from previous page
rinse occurs for the time period set in
                                            from 1st page
step 6. While rinsing, the operator
                                                                    if              Turn spray_1 ON
panel will display the fact that the sec-                     station 1 step then   Turn top and side
ond rinse is occuring and count down                              =7                brushes OFF
                                                                    ?
the rinse time. When the process timer                               else
times out, the wash state will be ad-
                                                                                           if              display “Second
vanced to 3 and the station 1 step reset                                             update_display then   Rinse” & number of
to 0. By looking at this flow chart, you                                               = TRUE
                                                                                           ?
                                                                                                           seconds remaining
can see that once the wash step is                                                          else
changed from 2, this flow chart will no
longer control the process. The Car-
                                                                                          if
Wash program will next activate the                                                  process time then     station1_step = 0
                                                                                                           wash state = 3
ConveyorControl ladder logic chart to                                                  complete
                                                                                           ?
control the process of moving the car
                                                                                            else
to the second station.




                                              Return




                                                                                                                          10
AN-PTCA001                         Nematron Pointe Controller Application                        The Car Wash



5.3 The Conveyor Control Ladder Chart                      The conyevor enable latching relay turns on the
                                                           comnveyor motor (rung 5). When the car is pulled
The ladder chart for conveyor control is shown be-
                                                           away from car sensor 1, the messages change to
low. The functionality of this ladder chart is enable
                                                           "Moving to station 2" and "switch ON when there"
when, in wash step 3, the CarWash flow chart turns
                                                           (rung 2). Normal completion occurs when car sense
on the conveyor enable bit. That bit is shown as the
                                                           2 becomes active (rung 3). Abnormal completion
conveyor enable contact on the first rung.
                                                           occurs when a conveyor jam is sensed (rung 4).
The closing of the conveyor enable contact will
                                                           Normal completion advances the wash state to 4 &
cause the messages, "Conveyor Enabled" and
                                                           initializes the step counter for the next operation,
"Clear car sensor 1" to be displayed one time. Since
                                                           stationTwo control. It also clears the conveyor en-
rung 1 has a latching coil output, conveyor_com-
                                                           able. All of this occurs in rung 3.
mand, whose normally open contact is in the path of
energization, this rung will be active on only the first
pass.                                                      Abnormal completion moves the wash state to 7.
                                                           (See the CarWash flow chart for more detail)




                                                                                                            11
AN-PTCA001                        Nematron Pointe Controller Application                                           The Car Wash



5.4 The StationTwo Flow Chart               StationTwo

Station Two's flow chart is shown on the
                                                                                              if
right. When the CarWash flow chart                if                  if                                        station2 step = 1
                                            wash state=4 then   station 2 step then      delux wash then        set process timer
advances to wash state 4, station 2's              ?                =0                     = TRUE               for 22 seconds
operations are enabled, as shown.                                     ?                       ?
                                                   else                else                    else

                                                                                      station2_step = 2
Our high quality car wash will first
check, in station2 step 0, if the users
                                                                                      set process timer
has selected a delux wash. If so, the                                                 for 10 seconds
chart advances to step 1. If not, it will
skip step 1 and go to step 2. In either
case the process timer will be set to the
                                                                      if
appropriate time for the process step.                          station 2 step then      Turn waxer ON
                                                                    =1
                                                                      ?
In step 1, the stationTwo flow chart will                              else
                                                                                                if               display “Applying
control the application of wash to the                                                    update_display then    Wax” &
                                                                                            = TRUE               number of
vehicle. It turns the waxer on. While                                                           ?                seconds remaining
the wax is being applied, the operator                                                            else
panel will display a message indicat-
ing that wax is being applied and the                                                          if
                                                                                          process time then      station2_step = 2
number of seconds remaining. When                                                           complete
the process timer times out, the station                                                        ?
                                                                                                                  set process timer
2 step will advance to step 2.                                                                    else
                                                                                                                  for 20 seconds


Flow chart step 2 controls the final
rinse. It turns the waxer OFF and the                                 if                  Turn waxer OFF
                                                                station 2 step then       Turn spray2 ON
spray on . The spray will occur for the                             =2
time period set. While spraying the                                   ?
                                                                       else
operator panel will inform the opera-                                                           if               display “Final Rinse”
                                                                                          update_display then    and number of
tor the the final rinse is occuring and                                                     = TRUE               seconds remaining
count down the time. On time out, the                                                           ?

stationTwo step will advance to 3.                                                                else


                                                                                                if
Step 3 will blow dry the vehicle for a                                                     process time then     station2_step = 3
preset period of time. When it is com-                                                       complete
                                                                                                 ?
plete, the station 2 operations are                                                               else            set process timer
complete. The wash state will be set to                                                                           for 25 seconds

5. This will disable the functionality of
this flow chart and pass control back to
the CarWash flow chart.                                               if                  Turn spray2 OFF
                                                                station 2 step then       Turn blower ON
                                                                    =3
                                                                      ?
                                                                       else
                                                                                                if               display “Blow Drying”
                                                                                          update_display then    and number of
                                                                                            = TRUE               seconds remaining
                                                                                                ?
                                                                                                  else


                                                                                                if               station2_step = 0
                                                                                           process time then     wash state = 5
                                                                                             complete            stop process timer
                                                                                                 ?
                                                                                                  else


                                               Return




                                                                                                                                    12
AN-PTCA001                        Nematron Pointe Controller Application                         The Car Wash



5.5 Preparing the Chart List & Setting                    fine for the Car Wash application, so simply click the
Parameters                                                OK.
One the program charts have been created and
prior to compiling the program, a few details must
be set up.
                                                          5.6 Compiling the Application
The next program development step entails defin-          Once the program charts have been entered, the
ing the chart list. Under the "Project" drop down         chart list established and the pref-
menu list, select "Configure Chart List". Once the list   erences selected, it is time to com-
somes up, move the four charts to Chart List side, as     pile the application. To do so, click
shown below. By moving charts to the left hand ta-        the "Build" icon, shown on the right,
ble, you define those charts as being the ones that       or select "Build Runtime" from the
will run as part of the application.                      Project drop down list.

                                                          A successful build will show messages in the mes-
                                                          sage window like those shown below. The key state-




                                                     ment is the last line, stat ing "Pro ject build
                                                     successful". Any other result will require correcting
                                                     a problem and re-building until the "Project build
The last set of parameters to set is found under the complete" is achieved.
"Edit" list. Select the "Preferences" selection. Tha
following screen will pop up.




The default setting indicate that the logic solve will
occur every 20 milliseconds, debug data will be sent
to the monitor every 250 milliseconds, if the control-
ler is hung up on anything for 5 seconds, it will be
reset, and the program source will be downloaded
into the Pointe Controller. These parameters are




                                                                                                             13
AN-PTCA001                       Nematron Pointe Controller Application                      The Car Wash



                                                      The only other connection is 12 or 24VDC power
       6.0 Connecting up the System                   connected to each base.
The configured Car Wash system is shown below.
                                                       The Pointe Controller and the OL4054 must be
Physically, the development PC, the Pointe Control-    configured with IP addresses in the same subnet
ler and the Ol4054 are all connected through a         address space.
hub. The OL3420 operator terminal is connected to
the Pointe Controller via a 10 pin ribbon cable. I/O
                                                     The link light should be on at the PC, Pointe Control-
modules are placed in the positions defined in the
                                                     ler and OL4054. If it is not, there is an interconnect
I/O Configuration for the program. Thosed place-
                                                     problem.
ments are as follows.

Pointe Controller :
   • Slot 1 (nearest the ethernet connection):
     OL2201 digital input simulator
   • Slot 2 : OL2108 Relay module
OL4054
   • Slot 1 : OL2201 digital input simulator
   • Slot 2 : OL2109 transistor output module




                               Pointe Controller, Ol4054 and
                               PC connected through hub




                                                                                                        14
AN-PTCA001                         Nematron Pointe Controller Application                         The Car Wash




      7.0 Downloading the Application
Once, the application has been developed and
built, it is time to download it to our
Pointe Controller system. With the sys-
tem configurea as shown in the previous
section, select the Monitor. You can se-
lect Monitor, either by double clicking
the Mon i tor icon (shown here), or
sleecting "Activate Monitor" from the drop down list,
under "Window".

When the Monitor window initially pops up, it will
look similar to that shown below. In this state, the
Monitor is showing you that no Pointe Controller is
attached.




                                                           (re)load", the click the "Load" button. If the current
                                                           build of the CarWash program is already in the
                                                           Pointe Controller, it will pop right back with a mes-
                                                           sage stating that "Project unchanged, load request
                                                           ignored". Otherwise it will spend some time con-
                                                           verting the progam to downloadable format, then
                                                           send it over the Ehernet link. If you look under the
                                                           "Console" tab, you can follow the conversion pro-
                                                           cess. After the conversion is complete, a progress
                                                           bar will pop up, as shown to show the download
                                                           progress.
Select your Pointe Controller from the drop down
list, next to "Controller". In this configuration, there
will only be one Pointe Controller listed. Select it.




The Monitor will take some time attaching to the
Pointe Controller, reading back any program that it
has loaded and reading back current status. If the
Pointe Controller is running, stop it by clicking the
"Stop" button, near the top of the Monitor window.

To download the program, select the CarWash pro-
gram from the drop down list next to "Project to




                                                                                                              15
AN-PTCA001                        Nematron Pointe Controller Application                         The Car Wash



8.0 Start-up & Operation                                  and start again, just select "Stop" on the Monitor,
                                                          and then "Reset" and Start. You can also simply
Once the program is downloaded, you are in a
                                                          "stop" the program for any period of time, the "Start"
postion to start and run it. All it takes is clicking the
                                                          it again. The program will pick up where it left off.
the "Start" button on the monitor. When you do that,

                                                          Since we don't want to ship a development PC with
                                                          each car wash controller, the Pointe Controller is
                                                          inteded to operate stand alone. Try it. Disconnect
                                                          the PC's ethernet cable. Power off the system.
                                                          Power it back up without the PC connected. The Car
                                                          Wash application will automatically start up [as-
                                                          suming that you left it in the run mode, ie started].




the program will starf. If you select the "Charts" tab,
you can see a list of the charts that are running.




You should be able to run through the car wash op-
eration at this point. Push the Start button on the
OL3420 operator panel. For the most part, the pro-
cess will execute and prompt you if and when you
need to do something. For operational details, look
at your charts. The nice thing about flow charts is
they are self documenting. You should be easily
able to follow the program flow.

As you run through washing a car, notice that com-
munications between the Pointe Controller and the
OL4054 RTU is continuous. Remote operations at
the OL4054 are instantaneous - as if the I/O was lo-
cal.

Once you run through the car wash, you should be
back to the beginning - ready to wash another car. If
you ever want to abort the process in the middle,



                                                                                                             16
AN-PTCA001                      Nematron Pointe Controller Application   The Car Wash




    9.0 Program Monitoring and Debug
If you download and execute the CarWash pro-
gram, it should come up and run perfectly the first
time. However, in developing an application, from
scratch, you'll need to go through a debug process -
unless you happen to be one of those rare individu-
als who always thinks of all the special cases that
might occur and never makes a mistake.

This sectioncovers basic debug and monitoring fea-
tures of the Pointe Controller - using the Car Wash
application. For more detail, go to the Pointe Con-
troller user's manual.

9.1 Monitoring Flow and Ladder Charts
With the Monitor running, select the "Charts" tab
and double click on the name of any of the charts.
The chart monitor will pop up as shown below.




If you click the "Enable flow logic" and "Enable de-
bug trace" icons, shown on the right,
The debug trace will turn on. The
trace will highlight in yellow the
real-time logic flow of your program in
yellow, at the top of the next column.




                                                                                  17
AN-PTCA001                        Nematron Pointe Controller Application                       The Car Wash



If you want to look at data, associated with a machinery is potentially dangerous. Click "Yes" to
particual block, just double--click on the block, and proceed.
a block watch window will pop up, like shown be-
low.                                                  The next time the program gets to the block that has
                                                      the breakpoint, the program flow chart will stop.

                                                          Note : Only the flow chart with the breakpoint
                                                          will stop. Other charts will continue to execute.
                                                          You must be careful that your actions do not
                                                          cause problems with real machinery and per-
                                                          sonnel, before setting a breakpoint.

                                                         Once you hit a breakpoint, you can use the single
                                                         step icons to step through your logic.

                                                         To clear a breakpoint, select the block and click the
                                                         breakpoint icon again. To put the flow chart back in
                                                         normal run operation, click the "Go" icon.
To monitor more data items or particular data items,
not necessarily associate with a particular block, set
up a watch window through the Monitor's browser
tab and bring it up by selecting the Watch window in
the "View" drop down list.

9.2 Breakpoints and Single Step Operations
Setting breakpoints and single stepping are very
fundamental debug operations. You generally
want to see exactly what your program does in cer-
tain situations. To set a breakpoint, select the pro-
gram block you want to break on, then click the




"Insert/Remove Breakpoint" icon, shown below. A
warning message, as shown, will pop up, informing
you that stopping a program when controlling real




                                                                                                           18
AN-PTCA001                       Nematron Pointe Controller Application   The Car Wash




                10.0 Conclusion
The pages of this application note have described a
typical control system application of the Pointe Con-
troller. The program itself was covered in some
depth, while downloading, and debug features
were just touched upon. The scope ot the applica-
tion note did not enable covering the array of soft-
ware, deployment and I/O features of the Pointe
Controller. There are many more such features and
deployment options available. These are described
in the Pointe Controller manual as well as other ap-
plication notes.

This application note was intended to illustrate the
ease of use, flexibility and power of the Pointe Con-
troller while stepping a new user through a simple
application. Its strength lies in those qualities as
well as the fact that it is designed to be deployable
as a node in a larger network. See other Nematron
and Optimation documentation for more informa-
tion.




                                                                                   19

				
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