Troubleshooting Procedure; Relay Calibration - Schweitzer Engineering Laboratories SEL-351-5 Instruction Manual

Troubleshooting Procedure

All Front-Panel LEDs Dark
1. Input power not present or fuse is blown.
2. Self-test failure.
Cannot See Characters on Relay LCD Screen
1. Relay is deenergized. Check to see if the ALARM contact is closed.
2. LCD contrast is out of adjustment. Use the steps below to adjust the contrast.
a) Remove the relay front panel by removing the six front-panel screws.
b) Press any front-panel button. The relay should turn on the LCD back lighting.
c) Locate the contrast adjust potentiometer adjacent to the serial port connector.
d) Use a small screwdriver to adjust the potentiometer.
e) Replace the relay front panel.
Relay Does Not Respond to Commands From Device Connected to Serial Port
1. Communications device not connected to relay.
2. Relay or communications device at incorrect baud rate or other communication parameter
incompatibility, including cabling error.
3. Relay serial port has received an XOFF, halting communications. Type <CTRL>Q to send
relay an XON and restart communications.
Relay Does Not Respond to Faults
1. Relay improperly set.
2. Improper test source settings.
3. CT or PT input wiring error.
4. Analog input cable between transformer secondary and main board loose or defective.
5. Failed relay self-test.
Relay Meter Command Does Not Respond as Expected
1. Global settings PTCONN, VSCONN, NFREQ, or PHROT not set correctly.
2. Group Settings CTR, CTRN, PTR or PTRN not set correctly.
3. Relay analog inputs not connected correctly.
R C
ELAY ALIBRATION
The SEL-351 Relay is factory-calibrated. If you suspect that the relay is out of calibration, please
contact the factory.
Date Code 20020426 Testing and Troubleshooting
SEL-351-5, -6, -7 Instruction Manual
13-9