| Metering Units represent the secondary values for the current and voltage transformers. That is Metering Units are the values present at the voltage and current inputs at the back of the meter. As an example, if the PTs (voltage transformers) have a ratio of 480:120 and the CTs (current transformer) have a ratio of 300:5; and you were injecting full secondary values (120 Vl-l and 5 A) for all three phases you would see the the following values: kw A = 120 V * 5 A = 600 W = 0.600 kW kw B = 120 V * 5 A = 600 W = 0.600 kW kw C = 120 V * 5 A = 600 W = 0.600 kW kw total = 0.600 kw + 0.600 kw + 0.600 kw = 1.80 kw |
*note: these calculation assume a unity power factor
*note: Metering Units can sometimes be referred to as "uncompensated" or "unscaled" values.
Udgivet til:Schneider Electric Danmark
