Common use of Testing Equipment Clause in Contracts

Testing Equipment. The goal is to accurately measure the TRUE power consumption2 of the MFD. This necessitates the use of a True RMS Watt-Hour Meter, one per phase, accurate to three figures. There are many Watt-hour meters to choose from, but manufacturers will need to exercise care in selecting an appropriate model. The following factors should be considered when purchasing a meter and setting up the actual test. To begin, it is important to understand that MFDs which contain switching power supplies draw current in a waveform different from typical sinusoidal current.3 Figure 1 shows the typical current 2True power is defined as (volts)x(amps)x(power factor), and is typically reported as ▇▇▇▇▇. Apparent power is defined as (volts)x(amps) and is usually expressed in terms of VA or volt-amps. The power factor for equipment with switching power supplies is always less than 1.0; so true power is always less than apparent power.