The Dytran model 4102C is current source power unit is a single channel, battery operated portable unit, designed to operate with IEPE accelerometer, pressure transducers and force sensors which contain integral amplifiers. IEPE sensors require a source of constant current, usually in the range of 2 to 20 mA, at a supply (compliance) voltage range of +18 to +30 VDC.

The current source power unit supplies a fixed constant current (called sensor drive current) to the sensor of 2 mA at +18 Volts compliance voltage level. Power to operate the sensor is supplied by two 9 Volt transistor radio type dry cell batteries, operating in series, to produce +18 Volts DC. A low current voltmeter located on the front panel of the 4102C constantly monitors the voltage appearing at the "Sensor" jack. This DC voltage is quiescent bias voltage of the sensor and measuring this voltage is very useful in testing for faulty operation of cables and sensors. A momentary pushbutton switched located just below the meter checks battery voltage without disturbing the test in progress. Both "Sensor" and "Output" jacks are BNC.