Schweitzer Engineering Laboratories SEL-421-4 - Table 2.6 Main Board Jumpers-JMP2, JMP3, and JMP4

2.19
Date Code 20171021 Instruction Manual SEL-421 Relay
Installation
Jumpers
Table 2.6 describes the JMP2, JMP3, and JMP4 positions. Refer to Figure 2.19
for the locations of these jumpers. The SEL-421 ships with JMP2, JMP3, and
JMP4 OFF (no +5 Vdc on Pin 1).
Changing Serial Port Jumpers
You must remove the main board to access the serial port jumpers. Perform the
following steps to change the JMP2, JMP3, and JMP4 jumpers in an SEL-421:
Step 1. Follow your company standard to remove the relay from service.
Step 2. Disconnect power from the SEL-421.
Step 3. Retain the GND connection, if possible, and ground the equipment to
an ESD mat.
Step 4. Remove the communications cable connected to the front-panel
serial port, if applicable.
Step 5. Remove the rear-panel EIA-232 PORT mating connectors.
Unscrew the keeper screws and disconnect any serial cables
connected to the PORT 1, PORT 2, and PORT 3 rear-panel receptacles.
Step 6. Remove any Ethernet and IRIG-B connections.
Step 7. Loosen the four front-panel screws (they remain attached to the front
panel), and remove the relay front panel.
Step 8. Remove the 34-pin ribbon cable from the front panel by pushing the
extraction ears away from the connector.
Step 9. Disconnect the power, the interface board, and the analog input board
cables from the main board.
Step 10. Carefully pull out the drawout assembly containing the main board.
Step 11. Locate the jumper you want to change.
Jumpers JMP2, JMP3, and JMP4 are located at the rear of the main
board, directly in front of PORT 3, PORT 2, and PORT 1,
respectively (see Figure 2.19).
Step 12. Install or remove the jumper as needed (see Table 2.5 for jumper
position descriptions).
Step 13. Reinstall the SEL-421 main board, and reconnect the power, the
interface board, and the analog input board cables.
Step 14. Reconnect the cable removed in Step 7 and reinstall the relay front-
panel cover.
Step 15. Reattach the rear-panel connections.
Table 2.6 Main Board Jumpers—JMP2, JMP3, and JMP4
Jumper
Jumper
Location
Jumper
Position
a
a
ON is the jumper shorting both pins of the jumper. Place the jumper over one pin only for OFF.
Function
JMP2 Rear OFF Serial PORT 3, Pin 1 = not connected
ON Serial PORT 3, Pin 1 = +5 Vdc
JMP3 Rear OFF Serial PORT 2, Pin 1 = not connected
ON Serial PORT 2, Pin 1 = +5 Vdc
JMP4 Rear OFF Serial PORT 1, Pin 1 = not connected
ON Serial PORT 1, Pin 1 = +5 Vdc
DANGER
Contact with instrument terminals
can cause electrical shock that can
result in injury or death.
WARNING
Have only qualified personnel service
this equipment. If you are not quali-
fied to service this equipment, you
can injure yourself or others, or cause
equipment damage.
CAUTION
Equipment components are sensitive
to electrostatic discharge (ESD).
Undetectable permanent damage can
result if you do not use proper ESD
procedures. Ground yourself, your
work surface, and this equipment
before removing any cover from this
equipment. If your facility is not
equipped to work with these compo-
nents, contact SEL about returning
this device and related SEL equip-
ment for service.