WHAT IS FIBER OPTICS?
Answer: In its simplest terms, fiber optics is a medium for carrying information from one
point to another in the form of light. Unlike the copper wire mode of transmission, fiber
optics is not electrical in nature.
WHAT ARE THE ADVANTAGES OF FIBER OPTIC SYSTEMS?
Answer: Fiber optic systems have the following advantages over copper wire systems:
Speed: Fiber optic systems operate at high speeds - up to gigabits.
Bandwidth: Fiber optic systems have large carrying capacity because light sources are
used for transmission.
Distance: Signals can be transmitted much further without needing to be regenerated or
Resistance: Fiber lines are inherently resistant to EMI/RFI and transient surges; therefore,
they are ideal for data communications near heavy electrical equipment and other
electrical or radio interference.
WHAT DO I NEED TO USE FIBER OPTIC SYSTEMS?
Answer: Fiber optic systems are used for transmitting information over long
distances. For example, RS-232 has a distance limitation of 16 ft (5m). Some projects
require the RS-232 data to be sent over long distances, if it is transmitted within 4000 ft
(1.2km), then you can probably use an RS-232 data repeater (such as 3onedata
Model232D). However, if the distance is over 4000 ft (1.2km), then a fiber optic system is
WHAT DOES A TYPICAL FIBER OPTIC SYSTEM CONSIST OF?
Answer: A typical fiber optic system consists of a transmitting device, which generates
the light signal; an optical fiber cable (one or two cores for transmitting and receiving),
which carries the light; and a receiver, which accepts the light signal that is being
transmitted. The fiber itself is passive and does not contain any active, generative
properties. For our products, the transmitting and receiving devices are built within the
same device. Sometimes we call it a Fiber Optic Converter or Fiber Optic Transceiver.
WHAT IS THE DIFFERENCE BETWEEN SINGLE-MODE (SM) AND MULTI-MODE
Answer: Two basic types of fiber and many different types of fiber optic cables are used
today. The two types of fiber are called Single-Mode (SM) and Multi-Mode (MM). SM
fiber is more expensive, but more efficient than MM fiber, SM fiber is generally used in
situations in which the distances to be covered are greater.
SM fiber is a single strand of glass fiber with a diameter of 8.3 to 10 microns that has one
mode of transmission. SM fiber comes with a relatively narrow diameter; the small core
and single light wave virtually eliminate any distortion that could result from overlapping
light pulses, providing the least signal attenuation and the highest transmission speeds of
any fiber cable type. The typical distances for SM fiber are 12.4 miles (20 km) to 62 miles
Multi-Mode fiber is a multi-strand of glass fiber with a diameter of 50 to 100
microns. Light waves are dispersed into numerous paths or modes, causing signal
distortion at the receiving end for long distance cable runs. The typical distance for MM
fiber is 1.2 miles (2 km).
Note: Fiber optic converter and fiber cable must be of the same type, e.g. SM fiber optic
converter must be used together with SM fiber cable, while MM fiber optic converter must
be used together with MM fiber cable.
WHAT ARE THE USABLE FIBER OPTIC CABLES FOR OUR FIBER OPTIC
Answer: Almost all Single-Mode and Multi-Mode cables are supported for our fiber optic
- Single-Mode: 8.3/125, 8.7/125, 9/125, 10/125µm;
- Multi-Mode: 50/125, 62.5/125µm.
WHAT CONNECTOR TYPES DOES OUR FIBER OPTIC PRODUCTS COME WITH?
Answer: Our fiber optic converters come with the options of ST and SC connectors.
ST: A keyed bayonet type similar to a BNC connector; it can be inserted into and removed
from a fiber optic converter quickly and easily.
SC: A push on/pull off connector with a plastic housing and a locking tab; it is one of the
earliest and most commonly used types.
WHAT IS THE WAVELENGTH FOR OUR FIBER OPTIC PRODUCTS?
Answer: The wavelength for our fiber optic converters is 1310nm
(nanometers). Wavelength and frequency are related, 1310nm falls into the frequency
range of infrared. The reason for infrared range frequency is that the attenuation of the
fiber is much less there.
HOW MANY CORES OF THE FIBER OPTIC CABLE DO I NEED IN ORDER TO
CONNECT OUR FIBER OPTIC CONVERTERS?
Answer: Our fiber optic converters work in pairs (point to point); two cores of the fiber
optic cable are required, one for transmitting and one for receiving.
WHAT IS THE MAXIMUM DISTANCE FOR THE RS-232, RS-485 AND RS-422
CONNECTIONS OF THE FIBER OPTIC CONVERTER?
Answer: The typical maximum distance for RS-232 is 16 feet (5 meters); for RS-485 and
RS-422, it is about 4000 feet (1.2 km).
WHAT IS THE MAXIMUM DISTANCE FOR 10 OR 100M ETHERNET OF THE FIBER
Answer: The typical maximum distance for 10/100M Ethernet is about 328 feet (100
meters) by using CAT5E twisted pair cable.
WHAT ARE THE TYPICAL FIBER LINK DISTANCES FOR OUR PRODUCTS?
Answer: Depending on the fiber cable and the type of converter used, a Multi-Mode
fiber optic link can go up to 1.2 miles (2 km), while a Single-Mode fiber optic link can go up
to 12.4 miles (20 km).
CAN I CONNECT AN RS-232 DEVICE TO ONE SIDE AND CONNECT RS-485 OR
RS-422 DEVICES TO THE OTHER SIDE OF THE FIBER LINK?
Answer: Yes. Standards can be mixed and matched, so an RS-232 device can be
connected to one side of the fiber link, and RS-485/422 devices to the other; or RS-485
(2-wire) devices can be connected to one side of the fiber link, and RS-422 (4-wire)
devices to the other, without using a converter and isolator.
ARE THERE ANY JUMPER OR DIP SWITCH SETTINGS FOR SERIAL DATA TYPES
OR BAUD RATES FOR YOUR RS-232 / RS-485 / RS-422 TO FIBER OPTIC
Answer: No. There are no jumper or DIP switch settings in the unit. Simply connect
the serial data into its respectively connectors and hook up the system. The Model277
series support data rates up to 460kbps and features data format auto-sensing and
self-adjusting, and therefore, no DIP switches or jumpers are required. When working with
RS-485 signals, the CommFront’s auto-turnaround feature eliminates the need for flow