How
Are AC/DC Hall-Effect Current Clamps Specified?
AC
CURRENT TRANSFORMERS
AYA
offers a very extensive line of precision clamp-on AC
current transformers that are specified just like standard
closed-core current transformers. The specifications of
an AC clamp includes the current range that it is designed
for, the output that it delivers at full scale, the input-output
current ratio, the size of the window opening, the voltage
rating, the accuracy and other parameters. Clamps whose
output signal is a current also include burden rating
in VA at a specified load resistance. Clamps that provide
a voltage output incorporate a current-to-voltage converter
and their specifications include a minimum load resistance
for obtaining the specified accuracy. Two such AC current
clamps are shown below.
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| Current
Clamp with Current Output |
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Current
Clamp with Voltage Output |
AC/DC
HALL-EFFECT CURRENT CLAMPS
Current Clamps
that can measure both AC and DC current simultaneously
incorporate such Hall-Effect sensors which are
placed in the path of the magnetic field of the clamp.
If the magnetic field is generated by an AC current under
measurement, the output is an AC signal. If the magnetic
field is generated by a DC current under measurement,
the output signal is a DC signal. An AC/DC clamp also
includes a battery and a signal conditioner which converts
the Hall-Effect output current into a calibratable
voltage that is available at the output terminals of the
clamp.
AYA AC/DC Microclamps
AYA AC/DC Mid-Size Current Clamp AYA AC/DC Current Clamp
- 7500 Amperes
The AYA AC/DC current
clamps are bidirectional. They can measure POSITIVE DC
current, NEGATIVE DC current, AC current or a combination
of AC and DC currents. Their current measuring range is
specified to indicate the full scale DC current and the
full scale AC current in Peak-to-Peak values. If the AC
current is a pure sinewave, its RMS value is 0.707 of
the sinewave peak, which is also 0.707 of the DC current
rating of the clamp. Its Peak-to-Peak value is twice the
DC current rating.
For Example:
The Model P3C-7500-A
current clamp has a full scale of either +7,500 Amperes
DC or -7,500 Amperes DC. However, it can also measure
accurately any AC current or AC/DC combination whose positive
peak is as high as +7,500 Amperes and whose negative peak
is as high as -7,500 Amperes. This can be expressed as
a rating of 15,000 Amperes Peak-to-Peak. If the current
is a pure AC sinewave, its RMS value is:
0.707 X 7,500 = 5,302.50
Amperes RMS.
AC/DC HALL-EFFECT
OPEN-FRAME CURRENT TRANSDUCERS
For high current
applications, AYA offers open frame Hall-Effect Transducers
that can measure up to 30,000 Amperes peak-to-peak and
15,000 Amperes DC. THey require an external power source
for the excitation circuit and for the internal signal
conditioner.
Open-Frame Hall-Effect AC/DC Current Transducer
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