MPC2000D
Issue 2 22/4/98
Page
5
3.1.5. Thermistor/RTD Inputs
Time Delay:
0.5 +/- 0.2 seconds
Thermistors
Range:
0.1 - 30 Kilo-Ohms
Accuracy:
+/- 0.1 Kilo-Ohm up to 5 Kilo-Ohm
+/- 3% above 5 Kilo-Ohm
RTD's
Range:
100 to 240 Ohms
Accuracy:
+/- 3%
Max. Wire Resistance:
25 Ohms
3.1.6. Overload Alarm and Trip Curves
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%
