Test Procedures – 7
7–21
Time Delay Accuracy Test
Test Settings:
Magnitude #1
60 V (0.50 pu)
Time Delay #1
5 cycles
Function 27
Disable
11. Press ENTER. The SELECT FUNCTION LED
should turn on and the unit should display
VOLTAGE RELAY
VOLT freq curr powr
C
12. Press ENTER. The unit should display
OVERVOLTAGE SETPOINTS
PHASE_OVER phase_under
C
13. Turn the knob clockwise to highlight
NUTRL_UNDER. Press ENTER. The unit
should display
NEUTRAL UNDERVOLTAGE #1
60 Volts (.50 PU)
14. Press ENTER. The unit should display
DELAY NEUTRAL UNDERVOLT#1
30 Cycles
15. Change the setpoint by rotating the knob
counterclockwise to 5 cycles. The unit should
display
DELAY NEUTRAL UNDERVOLT#1
5 Cycles
16. Press ENTER once and then EXIT until the
unit displays
BECKWITH ELECTRIC CO.
M-0420
17. Decrease the test voltage input to 55 V ac
and start timing. The unit should trip after 5
cycles ±1 cycle time delay.
18. The 27N UNDERVOLTAGE LED should turn
on and the unit should rotate displays
-TRGT- 06/22/93 10:19:12
Trip# = 11
-TRGT- 06/22/93 10:19:12
NEUTRAL UNDERVOLT #1
19. Reset the input voltage to 120 V ac.
20. Press TARGET RESET/LAMP TEST. The
27N UNDERVOLTAGE LED should turn off.
The unit should display
BECKWITH ELECTRIC CO.
M-0420
—END—
27N
RMS UNDERVOLTAGE, NEUTRAL CIRCUIT OR ZERO SEQUENCE (CONT)
Summary of Contents for M-0420
Page 56: ...M 0420 Instruction Book 3 4 This Page Intentionally Left Blank ...
Page 92: ...M 0420 Instruction Book 5 28 This Page Left Intentionally Blank ...
Page 156: ...A 8 M 0420 Instruction Book This Page Intentionally Left Blank ...
Page 160: ...B 4 M 0420 Instruction Book This Page Intentionally Left Blank ...
Page 164: ...C 4 M 0420 Instruction Book This Page Intentionally Left Blank ...
Page 166: ...D 2 M 0420 Instruction Book This Page Intentionally Left Blank ...
Page 174: ...E 8 M 0420 Instruction Book This Page Intentionally Left Blank ...