TRANSDUCER FOR ACTIVE AND REACTIVE POWER

• Datasheet (Adobe Acrobat Format)
• Unipolar output characteristic
• Bipolar output characteristic
• Live zero output
• Complies with IEC 60688
  

The transducer converts active or reactive power in an AC system into a load independent DC current or voltage signal which may be used to drive a number of remotely installed instruments.

Depending on the application, versions of this transducer are available for single phase and three phase (3 or 4 wire, balanced or unbalanced loads) measurement.

The multiplication of voltage and current signals may be either by means of analogue multipliers or by TDM methods, depending on the harmonic content of the signals.

MODE OF OPERATION

The voltage and current signals are transformed and multiplied. I transducers incorporating more than one multiplier, the various power signals are summated in (7). The output amplifier (8) provides either a load independent current signal (with maximum burden) or a load independent voltage signal (with minimum burden). The auxiliary voltage is transformed in (4), rectified and smoothed in (5) and is used to power the multiplier(s), summator, output amplifier and to provide offset voltage for live zero versions.

The 90 phase shift circuit (3) is required for single phase reactive power measurement.

Connection Diagrams

BA1 - REACTIVE POWER (kVAr) - single phase
WA1 - ACTIVE POWER (kW) - single phase

BA33B - REACTIVE POWER (kVAr) - 3 phase 3 wire balanced load

WA33B - ACTIVE POWER (kVAr) - 3 phase 3 wire balanced load

BA33U - REACTIVE POWER (kVAr) - 3 phase 3 wire unbalanced load
WA33U - ACTIVE POWER (kW) - 3 phase 3 wire unbalanced load

BA34U - REACTIVE POWER (kVAr) - 3 phase 4 wire unbalanced load
WA34U - ACTIVE POWER (kW) - 3 phase 4 wire unbalanced load

Technical Data

1.Input Quantities
Voltage:	All standard values up to 600V
Burden:	2.5mA maximum
Overload in terms of rated input:	1.73x indefinitely 2.5x 10 seconds
Current:	0-1A, 0-5A (other values on request)
Burden:	0.3VA at rated output
Overload in terms of rated input:	1.2x indefinitely 40x 0.5 second
Frequency:	45-55-65 Hz
2.Output
Characteristic:	A or B or D or E
Output quantity:	impressed current signal (voltage signal available on request)
Standard values:	1, 5, 20mA unipolar or bipolar
Maximum load:	10k, 2k, 500 Ohm (+50% on request)
Maximum output voltage:	15V DC (18V DC on request)
Maximum current output:	1.25x rated (typical) 2.00x rated (maximum)
Ripple:	0.5% standard
Response time:	210ms standard
3.Auxiliary Power Supply
Voltage:	110V, 220V 50Hz ±20%. (other values and DC on request)
Burden:	2.0VA at rated output
4.Accuracy
Error limit at rated conditions:	±0.5%(Watts), ±1.0%(Vars) at 23°C, 45-55Hz, cos phi=1
Linearity Error:	0.1%
Long term drift:	0.25%
Temperature Shift:	400ppm/°C
Variation with auxiliary supply:	0.05% for ±20% variation
Variation with power factor(Watt transducer)	Additional error max 0.5% at cos phi=0.5
5.Protection
Impulse test between isolated sets of terminals:	5kV (0.5J, 1.2/50 wave. IEC standard)
Voltage withstand rating between sets of terminals:	4kV, 50Hz AC for 1 minute
Power voltage across output:	220V 50Hz AC indefinitely
Surge across output terminals:	5kV, 25J 1kV, 4J
6.Physical Constraints
Working temperature:	-25°C to 13°C to 33°C to 55°C
Storage Temperature:	-55°C to 75°C (above dewpoint)
Relative Humidity:	80%
Variation due to external magnetic field(worst case):	0.05% at 400A/m, 50Hz
Position:	Surface mounting in any position indoors.
7.Enclosure	DIN B