DOOR MAINTENANCE

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					                             DOOR MAINTENANCE
INTRODUCTION

Maintaining a shielded enclosure within specifications over a number of years requires periodic inspection and
correction processes. Implementation of a regular scheduled maintenance program will ensure the enclosure is
kept in good condition. As the doors are the only moving parts, very little maintenance is required after the
enclosure has been properly installed.

GENERAL

Do not slam the door shut. Operate the door with a firm rotation of the handle, ensuring the action of the
latching mechanism is complete to give the final closed and RF tight position.

Check to see the floor and door areas are kept clean and clear of debris. Do not wet mop the floors. The
introduction of any moisture to the shielded enclosure may lead to corrosion of components and subsequent
degradation to the RF integrity of the enclosure. Check the operation of the door frequently and watch for the
accumulation of dirt and foreign objects. Keeping the door and frame clean on all contact surfaces will help to
maintain shielding effectiveness.

As a precaution to ensure the shielding integrity of the enclosure is maintained, holes should not be drilled in
either the panels or framework, or screws and nails put through the walls. If it is essential that fittings be
mounted to the walls or ceiling, the methods advised below under "Fitting of Internal Fixtures to Walls and
Ceiling" should be followed.

CLEANING

KNIFE EDGE DOORS
Taking care not to damage the contact fingers, lightly wipe down the beryllium copper contact fingerstrip using
a soft rag moistened with C.R.C. Formula 2.26 or similar solvent. To clean the recessed contact fingers on
knife edge doors, it will be necessary to carefully slide the cleaning cloth in between the two opposing rows of
fingers. It is recommended that the cleaning cloth be placed over a thin spatula (e.g. a plastic credit card or
wooden 'tongue depressor' (similar to an 'icy-pole' stick)). The brass 'knife edge' should also be cleaned. If
there is an excessive build up of dirt or verdigris (this is unlikely if regular cleaning is carried out), the brass
'knife' may be cleaned preferably using industrial "scotchbrite", or if this is not available using fine emery (e.g.
600 grit or higher).

COMPRESSION DOORS
Taking care not to damage the contact fingers, lightly wipe down the beryllium copper contact fingerstrip using
a soft rag moistened with C.R.C. Formula 2.26 or similar solvent. The door-frame of compression doors is
zinc sprayed. This contact area should be cleaned in a similar fashion to the contact fingers, and if necessary,
given a light rub with a plastic scouring pad such as "Scotchbrite". Do not use abrasives such as emery or
wire wool on the zinc sprayed surface as excessive use of abrasives may remove the zinc finish .

DOORS - GENERAL

On both compression and knife-edge doors, a regular check for damaged contact fingers should be made. If
any fingers are broken, it is important to determine how the fingers became damaged, and especially important
that any broken and grossly misshapen fingers are removed to ensure that further damage is prevented.

Damage to fingers on compression doors is known to happen through mishandling and grabbing the doors on
the outer edge, and also by accidental knocking or catching of the fingers by feet, equipment and loose
clothing.
                                                                                                       door maint rev2 0070.doc


                  RFI Industries Pty Limited                                    EMC ENGINEERS & LABORATORIES

52 – 54 Holloway Drive                         t     +61 (0)3 8739 6700                                        EMC TESTING
Bayswater Victoria 3153                        f     +61 (0)3 8739 6799                                   EMC COMPONENTS
AUSTRALIA                                                                                               MAGNETIC SHIELDING
                                               e     sales@rfi-ind.com.au                             EMC INSTRUMENTATION
P.O. Box 254                                   e     emclabs@rfi-ind.com.au                          RF ANECHOIC CHAMBERS
Bayswater Victoria 3153                                                                         RF/EM SHIELDED ENCLOSURES
AUSTRALIA                                      ABN           66 005 273 950
                                                                                                                                  1
                           DOOR MAINTENANCE
Although the recessed position of the fingers on knife edge doors provides a high degree of protection from
accidental damage, care should be exercised with these doors, and periodic checks made, to ensure that foreign
bodies do not get trapped within the recess.

Replace missing/broken beryllium copper "fingers" as necessary.             For finger replacement instructions refer
below to paragraph 7-22 - REPAIRS.

ROUTINE MAINTENANCE - PERIODICALLY

Ensure that the door latch assembly operates smoothly. The Cam Roller on the door latch is a sealed bearing
and does not require any maintenance. Similarly, the door hinges are fitted with sealed bearings by RFI
Industries and do not require any maintenance. The handle assembly is set during production and should not
require further adjustment. In the event that wear is observed on any of these items, RFI Industries should be
consulted.

Periodically (every 6-12 months depending on use) remove the cover to the Gear and Rack Assembly and
lubricate the gear and rack with general-purpose grease (Castrol LM Multi-purpose or equivalent). The
lubricant should be used very sparingly to avoid contamination of RF gaskets. Refer to Drawing No 10008(1).

Periodically (every 6-12 months depending on use) apply general-purpose grease (Castrol LM Multi-purpose
or equivalent) to the internal brass slides via the open slots at top and bottom of the door latch mechanism.

DOOR ADJUSTMENT

KNIFE EDGE DOORS

During manufacture, the door will be adjusted so that it is appropriately aligned with the frame and the recess
containing the contact fingers. Under normal operating conditions, there should be no need to carry out
further adjustments to the door. If however, a row of contact fingers become damaged, this may be as a result
of damage or impact to the door causing it to become misalignment with the frame. If a misalignment is
suspected, this should be checked, using Figures 3 to 5 as a guide to tolerances.


Although adjustment screws are fitted to the hinges allowing simple vertical adjustments to the door, there is
no simple adjustment that may be made to correct horizontal or rotational misalignments. It is strongly
recommended that an RFI Industries representative only carry out all door adjustments.

COMPRESSION DOORS

The door will normally be adjusted for correct pressure of the contact strips prior to shipment. If the door
requires either an inward or outward adjustment for correct compression of the contact strip, a small degree of
adjustment is possible by the judicious insertion or removal of shims under the hinge. On the locking side of
the door, a small amount of adjustment of the cams is possible by the insertion or removal of shims.

The compression is normally set so that when a small piece of paper is inserted between fingers and frame and
the door is closed, the paper should be very firm to pull out. This is a guide only, and only carrying out a
formal RF attenuation test can provide proof of adequate adjustment.

It is strongly recommended that all adjustments be carried out by RFI Industries representatives who are
familiar with the tolerances permitted.

                                                                                                          door maint rev2 0070.doc


                  RFI Industries Pty Limited                                       EMC ENGINEERS & LABORATORIES

52 – 54 Holloway Drive                       t     +61 (0)3 8739 6700                                             EMC TESTING
Bayswater Victoria 3153                      f     +61 (0)3 8739 6799                                        EMC COMPONENTS
AUSTRALIA                                                                                                  MAGNETIC SHIELDING
                                             e     sales@rfi-ind.com.au                                  EMC INSTRUMENTATION
P.O. Box 254                                 e     emclabs@rfi-ind.com.au                               RF ANECHOIC CHAMBERS
Bayswater Victoria 3153                                                                            RF/EM SHIELDED ENCLOSURES
AUSTRALIA                                    ABN           66 005 273 950
                                                                                                                                     2
                                DOOR MAINTENANCE
REPAIRS

REPLACING CONTACT FINGER-STRIP

Whenever damaged or broken contact fingers are discovered, it is important to examine the door to try and
determine the cause of the damage, and more importantly to ensure that loose and broken bits of finger are
removed so as to not to cause further damage to other fingers.

Contact fingers are generally one of three types:

Non self-adhesive (for knife-edge doors).

Self-adhesive (for knife-edge doors).

Clamped fingers on special doors.

FINGERS – Non Self-Adhesive (as used on knife edge doors)

In 1998, RFI Industries introduced a non self-adhesive contact strip for the knife edge door. Applicable part
numbers are 0097-0515-47 (or the ultrasoft version 0098-0515-47). These are applied to rooms with a serial
number greater than S931. The doors still use some self-adhesive contact strip so it is important to check the
identity of the correct part when ordering spares. Self-adhesive part numbers are 0097-0515-17 and 0098-
0515-17.

To ensure adequate contact of the replacement section of finger-strip it will be necessary to replace at least 30
cm (12 ins) of strip. Accordingly, even if a much shorter section of contact strip is actually damaged, at least
30 cm should be removed by carefully cutting both ends of the section to be repaired with a Stanley knife and
lifting out the damaged section. The contact area should be thoroughly cleaned to ensure that the contact
surface is free from any dirt, grease or other contaminant.
                                                                             100mm
                                                                             Typical


                          600mm
                          Typical
                                                                                 100mm
                                                                                 Typical




Typical locations of Self-adhesive (shaded) finger strip.

                                                                                                        door maint rev2 0070.doc


                  RFI Industries Pty Limited                                     EMC ENGINEERS & LABORATORIES

52 – 54 Holloway Drive                        t     +61 (0)3 8739 6700                                          EMC TESTING
Bayswater Victoria 3153                       f     +61 (0)3 8739 6799                                     EMC COMPONENTS
AUSTRALIA                                                                                                MAGNETIC SHIELDING
                                              e     sales@rfi-ind.com.au                               EMC INSTRUMENTATION
P.O. Box 254                                  e     emclabs@rfi-ind.com.au                            RF ANECHOIC CHAMBERS
Bayswater Victoria 3153                                                                          RF/EM SHIELDED ENCLOSURES
AUSTRALIA                                     ABN           66 005 273 950
                                                                                                                                   3
                             DOOR MAINTENANCE
Caution: Extreme care must be taken when attempting this procedure to ensure that the contact fingers do not
become distorted

SELF ADHESIVE FINGERS

To ensure adequate adhesion of the replacement section of contact strip it will be necessary to replace at least
30 cm (12 ins) of strip. Accordingly, even if a much shorter section of contact strip is actually damaged, at
least 30 cm should be removed by carefully cutting both ends of the section to be repaired with a Stanley knife
and lifting out the damaged section.

The contact area should be thoroughly cleaned to ensure that the contact surface is free from any dirt, grease or
residual adhesive. Adhesive can only be properly removed with ethyl alcohol or methyl ethyl ketone (MEK).

When replacing self-adhesive contact strips, it is essential that pressure is applied to the back of the adhesive
surface along the fullest length possible. In the case of contact finger 0097-0538-17 (or 'ultra-soft' version
0098-0538-17 as are most commonly fitted to compression doors, running the flat surface of a knife or similar
instrument under each of the fingers when the strip is in place does this.

Caution: Extreme care must be taken when attempting this procedure to ensure that the contact fingers do not
become distorted. In the case of contact finger 0097-0515-17 (or 'ultra-soft' version 0098-0515-17) as are
commonly fitted to knife edge doors i.e. where the contact fingers are fitted within in a protective channel, the
recommended method of fitting is to remove the protective tape from the adhesive, carefully position the strip
in the channel then press up on the fingers with a steel rule. This will hold the fingerstrip in place until the
door is closed. Opening and closing the door 6-7 times will normally apply sufficient pressure to positively fix
the fingers in position.

CLAMPED FINGERS

Loosen the screws in the brass retaining strip, ease out, and cut off the length of damaged contact strip.
Replace with new contact strip (ensuring that appropriate 'notches' are cut out to allow the strip to fit around
screws) and retighten the retaining strip.

Note: To ensure adequate clamping of the replacement fingers, it is recommended that the length of
replacement fingers be at least as long as the distance between three screws of the retaining strip. It is also
recommended that the contact area be examined (including the surfaces beneath the retaining strip) to ensure
that the contact area is clean of dirt, grease and any corrosion.

DAMAGED PANELS

Should the cladding of the panel edges show signs of lifting, it may be held down by Araldite or similar
adhesive on the extreme edge. The unpainted contact area of the panel should be kept clean, small dents or
penetrations can be filled with solder and smoothed out by sanding, making sure to remove all flux to avoid
corrosion.

PAINTING

If it is necessary to repaint the enclosure at any time, care should be taken not to paint the contact areas. If the
paint is applied to the joint between framework and panel, capillary action may draw the paint into the contact
area and reduce attenuation.

                                                                                                       door maint rev2 0070.doc


                  RFI Industries Pty Limited                                    EMC ENGINEERS & LABORATORIES

52 – 54 Holloway Drive                         t     +61 (0)3 8739 6700                                        EMC TESTING
Bayswater Victoria 3153                        f     +61 (0)3 8739 6799                                   EMC COMPONENTS
AUSTRALIA                                                                                               MAGNETIC SHIELDING
                                               e     sales@rfi-ind.com.au                             EMC INSTRUMENTATION
P.O. Box 254                                   e     emclabs@rfi-ind.com.au                          RF ANECHOIC CHAMBERS
Bayswater Victoria 3153                                                                         RF/EM SHIELDED ENCLOSURES
AUSTRALIA                                      ABN           66 005 273 950
                                                                                                                                  4

				
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