angle of 0°. Note, the DC voltage transducer is identical, except instead of 50 or 60 Hz as
the default output frequency, the display changes to read DC.
When the test is Started, the measured voltage output is displayed. This is the value that
gets displayed in the Transducer Test Screen under the MPRT Output, next to the
Label of AC Voltage or DC Voltage. Another value of Volts gets calculated using the
measured dc Volts or dc milliampere output as displayed in the Transducer Output
section. Let us assume that in our example transducer, the output is in dc milliamperes.
For this example, let us say that 1 miiliampere of dc current is equal to the full scale
output of 150 Volts. Therefore, the theoretical output Volts from the transducer would be
150 Volts, if the output current is 1 milliampere. For this example, let's say that the
measured output voltage of MPRT is 150.01 Volts.
For this example, let's assume the measured output current from the transducer is 0.999
mAmperes. Based on a Max. value of 1 mA equals 150 Watts, the displayed AC Volts in
the Transducer Output section of the Transducer Test Screen should read 150 *
0.999 = 149.85 Volts
The Accuracy displayed in the Transducer Output section would be equal to the
following,
(149.85 - 150.01 / 150.01) * 100 = % accuracy or
-0.106 %
If this were a 0.2 % transducer, then the firmware would compare the accuracy values
between the Setting Screen and the Test Screen and would display PASS in the
Transducer Output section of the test screen.
Note: All of the calculations are very similar when testing DC Voltage
transducers
3.8.10.8.2 AC and DC Current Transducers
The single phase AC or DC current transducer requires 1 current to test. The MPRT will
automatically select the first current channel available, I1. The test will initially start at the
default value current that is set in the Default Setting Screen. For example, 5 Amperes.
When the user inputs the MAX. Current value in the Transducer Setting Screen, the
firmware will automatically set the test current for full scale value. Note: to power up the
amplifier of some transducers, V1 may be selected to provide the AC voltage source.
Remember to select the proper output voltage for V1 (it will be set to the System Default
value in the setting screen).
Example: The default current is 5 Amperes AC, and the user inputs 5 Amperes AC as
Max. Value. Therefore, when the user inputs 5 Amperes in the MAX. value window, the
test set should automatically show a test current value of 5.000 Amperes at an angle of
0°. Note, the DC current transducer is identical, except instead of 50 or 60 Hz as the
default output frequency, the display changes to read DC.
When the test is Started, the measured test current output is displayed in the
Transducer Test Screen under the MPRT Output, next to the Label of AC Current or
DC Current. Another value of Current gets calculated using the measured dc Volts or dc
milliampere output as displayed in the Transducer Output section. Let us assume that
in our example transducer, the output is in dc milliamperes. For this example, let us say
that 20 milliampere of dc current from the transducer is equal to the full scale output of 5
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