BECKWITH ELECTRIC Syncrocloser M-3410A, Instruction Book

Page: 104 / 225

Configuration and Settings – 3
3–33
IECI IECVI IECEI IECLTI
Save
Cancel
Pickup:
Time Dial:
0.50 A
0.5
6.00 A
11.0
Outputs
Blocking Inputs
2 1 2 1 FL
Curves
Definite Time Inverse Time Very Inverse Extremely Inverse
#1
(51N) Inverse Time Residual Overcurrent X
Figure 3-38 M-3810A IPScom
®
for Windows™ (51N) Inverse Time Residual
Overcurrent Setup Dialog Screen
Path : Relay/Setup/Setpoints/51N Inverse Time Residual Overcurrent
COMMAND BUTTONS
Save Saves all entered information to the control.
Cancel Returns you to the previous window; any changes to displayed information are lost.
51N Inverse Time Residual Overcurrent
The Inverse Time Residual Overcurrent (3 I
0
) function
(51N) provides protection against ground faults.
Since normal residual current is usually much lower
than the full load phase current, this function can
be set more sensitively than the phase overcurrent
protection.
The setting and time delay should be coordinated
with system elements to assure desired operation.
The curves available for use are shown in Appendix
D, Inverse Time Curves, Figures D-1 through D-8.
They cover a range from 1.5 to 20 times pickup.
For currents beyond 20 times the pickup setting,
the relay operating time will remain the same as the
20 times pickup setting.