Measurement Ranges and Accuracy
The accuracy of the current measurements depends on both the value displayed (or transmitted) and the circuit-breaker rating, where:
Accuracy = 0.5% In + 1.5% reading
Example:
For a circuit breaker with a 4000 A rating and a current displayed on MicroLogic trip unit of 49 A, the accuracy is:
0.5% x 4000 + 1.5% x 49 = ±21 A
|
Measurement type |
Measurement |
Range |
Accuracy at 25 °C |
|
Instantaneous current |
I1, I2, I3 |
0.05 x In to 20 x In |
±1.5% |
|
IN |
0.05 x In to 20 x In |
±1.5% |
|
|
I |
0.05 x In to In |
±10% |
|
|
I |
0 to 30 A |
±1.5% |
|
|
I1 max, I2 max, I3 max |
0.05 x In to 20 x In |
±1.5% |
|
|
IN max |
0.05 x In to 20 x In |
±1.5% |
|
|
I |
0.05 x In to In |
±10% |
|
|
I |
0 to 30 A |
±1.5% |
|
|
Demand current |
I1, I2, I3 |
0.05 x In to 20 x In |
±1.5% |
| IN |
0.05 x In to 20 x In |
±1.5% |
|
| I1 max, I2 max, I3 max |
0.05 x In to 20 x In |
±1.5% |
|
| IN max |
0.05 x In to 20 x In |
±1.5% |
|
|
Phase-to-phase voltages |
U12 |
170 to 1150 V |
±0.5% |
|
U23 |
170 to 1150 V |
±0.5% |
|
|
U31 |
170 to 1150 V |
±0.5% |
|
|
Phase-to-neutral voltages |
V1N |
100 to 1150 V |
±0.5% |
|
V2N |
100 to 1150 V |
±0.5% |
|
|
V3N |
100 to 1150 V |
±0.5% |
|
|
Average voltage |
U avg |
170 to 1150 V |
±0.5% |
|
Voltage unbalance |
U unbal |
0 to 100% |
±0.5% |
|
Instantaneous power |
P |
0.015 to 184 MW |
±2% |
|
Q |
0.015 to 184 Mvar |
±2% |
|
|
S |
0.015 to 184 MVA |
±2% |
|
|
Power factor |
PF |
-1 to +1 |
±2% |
|
Demand power |
P |
0.015 to 184 MW |
±2% |
|
Q |
0.015 to 184 Mvar |
±2% |
|
|
S |
0.015 to 184 MVA |
±2% |
|
|
P max |
0.015 to 184 MW |
±2% |
|
|
Q max |
0.015 to 184 Mvar |
±2% |
|
|
S max |
0.015 to 184 MVA |
±2% |
|
|
Total energy |
E.P |
-1010 GWh to +1010 GWh |
±2% |
|
E.Q |
-1010 Gvarh to +1010 Gvarh |
±2% |
|
|
E.S |
-1010 GVAh to +1010 GVAh |
±2% |
|
|
Total energy in |
E.P |
-1010 GWh to +1010 GWh |
±2% |
|
E.Q |
-1010 Gvarh to +1010 Gvarh |
±2% |
|
|
Total energy out |
E.P |
-1010 GWh to +1010 GWh |
±2% |
|
E.Q |
-1010 Gvarh to +1010 Gvarh |
±2% |
|
|
Frequency |
F |
45 Hz to 440 Hz |
±0.1% |