Manual

Appendix G Data Scales
224 EM920 Power Quality and Revenue Meter
Appendix G Data Scales
The maximum values for volts, amps and powers in the
EM920 setup and in communications are limited by the
voltage and current scale settings. See Device Options and
Mode Control in Chapter 5 on how to change the voltage and
current scales in your meter.
The following table shows the meter data scales.
Scale Range
Maximum voltage (V max)
Voltage scale × PT Ratio, V
1
Maximum current (I max)
Current scale × CT Ratio, A
2, 3
Maximum Power (P max)
4
V max × I max × 2, W
Maximum frequency 100 Hz
1
The default voltage scale is 144V (120V+20%).
2
CT Ratio = CT primary current/CT secondary current
3
The default current scale is 4 × CT secondary (4.0A with 1A
secondaries and 20.0A with 5A secondaries).
4
Maximum power is rounded to whole kilowatts. With
PT=1.0, it is limited to 9,999,000 W.