ESAB EPP-400 Manuel D'instructions page 312

section 6
6.11 current transducer for optional output current monitoring
A spare Current Transducer is available for optional remote output current monitoring. The Current Transducer is some-
times referred to as a Hall Sensor or a Hall Transducer. The word, "Hall," comes from the expression, "Hall effect." The Hall
effect is the underlying principle for the transducer operation. Such a transducer is capable of accurately monitoring either
AC or DC currents carried by the conductor(s) passing through an opening in the transducer. The transducer monitors
the current without making any connection to the circuit being monitored. Therefore, the sensing circuitry is galvanically
isolated from the power source output.
To utilize the signal from the Current Transducer, the remote sensing circuitry must contain both positive and negative
15VDC bias supplies capable of providing 250 mA. A 5.00 Ohm resistor connected in the signal path acts as a shunt. The
current signal from the Current Transducer is equal to the monitored current divided by 5000. Therefore, 400A power
source output current results in 80.0 mA current through the 5 Ohm shunt resistor. 80.0 mA through 5 Ohms provides 400
mV across the resistor, thus the signal is 1.0 mV per Ampere output. A standard meter set to read millivolts will accurately
display the output current in Amperes.
ESAB has tested two transducers, one each from two vendors. The recommended circuit using the ±15V bias supplies and
the 5 Ohm resistor is compatible with both transducers.
The two tested transducers are:
(1) LEM P/N LF-505S
Technical information can be found at http://www.lem.com
use "LF 505S" as the search criteria.
(2) ABB P/N ES500C
Technical information can be found at http://www.abb.com
use "ES500C" as the search criteria.
312
troubleshootinG