T&R 200A-3PH mk2, Руководство по эксплуатации и техническому обслуживанию

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1.5.3 Phase Measurement
The 200A-3PH mk2 auxiliary metering circuit may be used to measure the phase difference
between one of the phases of the main output current and the auxiliary metering input.
1.5.3.1 Phase measurement between output current and an external voltage
Certain relays and transducers require the injection of a current and the application of a
phase-shifted voltage (e.g. directional relays). In such situations, the auxiliary metering circuit
may be used to measure the phase angle between the 200A-3PH mk2 output current and an
externally generated phase-shifted voltage. The circuit configuration is shown below using a
T&R Test Equipment DVS3 mk2 voltage source. The AUX METERING MODE switch should
be set to “PHASE”.
Figure 1.19 Phase measurement
When measuring the phase angle between the output current and an external voltage, the
200A-3PH mk2 defines the voltage generated across a resistive load in phase with the
current. Connecting a resistor as shown in figure 1.19 will therefore result in a voltage in
phase with the output current from phase A.
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