
3-40-0003-00 Printed in USA
TESTING
Models 5843 and 5844 are easily tested. Testing the units can be done by setting the Test mode switch that
transmits 100 Hz signal on the optical transmit port or requires transmitting and receiving data using an IED
while observing that the diagnostic LEDs are illuminating in the proper sequence.
To test whether a unit is transmitting and receiving correctly, insert a short fiber jumper between its "T" and
"R" optical ports, power the units, transmit a signal or set the test mode switch to ON and note that all four
diagnostic LEDs illuminate during communications.
To test the units in a loop configuration, two Link/Repeaters are required. Connect two short jumper fibers
from the "T" optical port of each Link/Repeater to the "R" optical port of the other. Set the Mode switch on one
of the units to REP and the other to OFF. The unit with the Mode switch in the OFF position is the Master.
Power both units. Using the Master, set the Test mode switch to ON or transmit and receive data through the
other unit in the repeat mode. Observe the diagnostic LEDs illumination patterns during communication.
TROUBLE SHOOTING
If the unit does not work properly, refer to the User Manual (UM5843), and use the following check list:
1. Is the unit properly powered?
• Verify the unit is receiving the correct power.
2. Check that the diagnostic LEDs are responding to the optical and electrical activity.
3. Is the unit mated properly to the IED? If an adapter is used, check that pin assignments are con-
nected correctly.
4. Are the fiber cables connected properly? "T" to "R"; not "R" to "R" nor "T" to "T".
5. Are the DTE/DCE and mode switches set to the proper positions for the application?
6. Review the IED's software and protocols. Does the IED have physical "Handshaking" requirements
and have the appropriate settings on the IED been made to compensate for these requirements.
7. Consult factory.
Pinout for DTE Mode (Normal Functionality) Pinout for DCE Mode (Normal Functionality)
2 Transmitted Data (Link Input) 2 Received Data (Link Output)
3 Received Data (Link Output) 3 Transmitted Data (Link Input)
5 Signal Common 5 Signal Common
(Extended Functionality) (Extended Functionality)
1 Chassis (Earth) Ground 1 Chassis (Earth) Ground
6 Data Set Ready (+5v output) 6 Data Set Ready (+5v output)
8 TTL Output 8 TTL Output
7 Repeat Enable / Disable 7 Repeat Enable / Disable
9 +9 to 15 Vdc Input 9 +9 to 15 Vdc Input
DO NOT ATTEMPT TO DISASSEMBLE LINK/REPEATERS AS THERE ARE NO SERVICEABLE PARTS WITHIN.
THIS ACTION WILL VOID THE WARRANTY.
25 Commerce Way #1 • North Andover, MA 01845
Phone 978 688-8807 • FAX 978 688-8771
IS5843zRevision AD
www.garrettcom.com