13-44
Testing and Maintenance
BE1-951
Auxiliary Undervoltage and Overvoltage Pickup Verification (3rd harmonic Vx input)
Step 1
Prepare the 27X and 59X/159X pickup functions for testing by transmitting the commands in Table
13-61 to the relay. Reset targets.
Table 13-61. 27X and 59X/159X Pickup Test Commands
Command
Purpose
A=
Gain write access
SL-N=NONE
Zero out custom logic settings.
Overwrite with logic=none settings.
Y
Confirm overwrite
SL-N=27X_59X/159X
Sets 27X_59X/159X as custom logic name
SG-VTX=1,AN
Set auxiliary voltage parameters
SL-27X=3,0
Enables 27X, disables blocking
SL-59X/159X=3,0
Enables 59X/159X, disables blocking
SL-VO1=27XT+59XT/159XT
Enables OUT1 to close for 27X or 59X/159X trip
SG-TRIG=27XT+59XT/159XT,
27XPU+59XPU/159XPU,0
Enables 27XT + 59XT/159XT to log trigger fault
recording.
EXITY;Y
Exit and save settings
Step 2 Using Table 13-62 as a guide (same values as the fundamental test but at 3rd harmonic
frequency), transmit the first row of setting commands (highest 27X PU, lowest 59XPU/159X PU)
to the relay.
Table 13-62. 27X and 59X/159X Pickup Settings
Pickup Settings
Purpose
Undervoltage
Overvoltage
S0-27X=70,50ms
S0-59X/159X=90,50
ms
Sets 27X PU at 70 V, 59X/159X at 90 V, TD
at min
S0-27X=60,50ms
S0-59X/159X=100,
50ms
Sets 27X PU at 60 V, 59X/159X at 100 V, TD
at min
S0-27X=50,50ms
S0-59X/159X=110,
50ms
Sets 27X PU at 50 V, 59X/159X at 110 V, TD
at min
Step 3 Prepare to monitor the 27X and 59X/159X function operation. Operation can be verified by
monitoring OUT1.
Step 4
Connect and apply a single-phase, 80 Vac, 3rd harmonic voltage source to terminals C17 (polarity)
and C18 (non-polarity). Refer to Figure 13-1 for terminal locations.
Step 5 Slowly decrease the voltage until OUT1 closes. Pickup should occur 2 percent or 1 volt of
the pickup setting. Slowly increase the voltage until OUT1 opens. Dropout should occur between
102 and 103 percent of the actual pickup value. Verify the 27-3 Bus target on the HMI.
Step 6
Continue to increase voltage until OUT1 closes. Pickup should occur 2 percent or 1 volt of
the pickup setting. Slowly reduce the voltage until OUT1 opens. Dropout should occur between 97
and 98 percent of the actual pickup value.