15/05/96
7
MPC2000 01/96B
Fault Time Accuracy:
+/- 1 second up to 10 seconds
+/- 1 /- 2% above 10 seconds
Threshold Current Level: Overload S/- 1.5%
3.1.7. Current Unbalance Alarm and Trip
Method:
Unbalance = 100 x (Imax - Imin) / Ir %
Where Imax = max. of 3 phase currents
Imin = min. of 3 phase currents
Ir = Larger of Imax or Motor FLC
Alarm
Threshold Unbalance Level:
50% of Unbalance c/- 2%
Fixed Time Delay Accuracy:
1.0 +/- 0.5 seconds
Trip Curves
Threshold Unbalance Level:
Unbalance Current S/- 2%
Trip Time Accuracy:
+/- 1 second up to 10 seconds
+/- 1 /- 2% above 10 sec.
3.1.8. Fault Time Delays
Accuracy:
+/- 0.5 seconds or +/- 2% of time
Exceptions
High Set Over-current:
-0.1 to +0.2 sec. up to 1 second
Earth Fault Trip:
-0.1 to +0.2 sec. for less than
1 second delayTotal Run Time
Accuracy:
+/- 2%
3.1.9. Relay Contacts
Rated Load:
8A @ 250V AC/8A @ 30V DC (Resistive)
6A @ 250V AC/3A @ 30V DC (Inductive)
Maximum Operating Voltage:
280V AC, 125V DC
Maximum Operating Current:
8 Amps
Minimum Permissible Load:
5V DC, 100mA
Note:
AC Inductive load PF = 0.4
DC Inductive Load L/R = 7mS
3.1.10. Dielectric Strength
2000V AC for 1 minute, between ground and:
