Yokogawa 2377A31 - Power Factor Transducer, 45-65 Hz, Three phase 3 wire

• Compact width 40 mm
  40 mm: DC-DC Isolator, AC current, AC voltage and Frequency. 55 mm: Power, Reactive power, Phase and power Factor Terminal cover: provided for every type.
• Auxiliary power applications
  Applicable from non auxiliary power to AC or DC auxiliary power.
• Various output signals
  Constant voltage outputs: 5 V, 10 V, 1 - 5 V
  Constant current outputs: 1 mA, 5 mA, 4-20 mA
  Especially, the constant current type canconnect a load corresponding to 10 V. So, it can stand with long distance wiring for such telemeter
  transmission and general industrial measurement.
• True RMS rectified type 2374A
  For general application and high harmonic distortion wave caused by thyristor, the true RMS rectified type with logarithm conversion is recommended.

Wiring Connections

• Any of the drawing shows AC input through external CT and/or VT. But direct input wiring is available. In case of direct input, secondary ground of CT and VT is not necessary.
• Any of the drawing has auxiliary power, however, there is type of non required auxiliary power in measurement of power, reactive power, phase, power factor and frequency.
• Type 5V and 1mA of voltage, current transducer 2372A or 2373A does not require auxiliary power.

AC Voltage / Current Transducer functional principle

1. Average rectified (2372A)
   A rectifier that makes proportional output to average of AC converts to DC. With related to RMS AC value, it calibrates output so that in no case of wave distortion, DC is output in proportional to input RMS. In case of 0-5 V or 0-10 mV, it does not need auxiliary power.
2. RMS rectified (2373A)
   AC-DC converter circuit consists of only passive element for RMS calculation of item 4 right. An advantage to average rectified is able to stand wave distortion. This model also does not need auxiliary power.
3. True RMS rectified (2374A)
   To realize RMS calculation of item 4 below, it uses AC-DC converter circuit being called as log-antilog method. For wave distortion, accurate RMS value is output. The distortion wave containing more than 15% of third harmonic wave is also output within specified accuracy. Auxiliary power is required.
4. RMS calculation