4115B

Dytran model 4115B is a high-precision constant current power unit designed to support IEPE sensors in low-frequency and thermally sensitive environments. Unlike conventional AC-coupled systems that use a 10 µF capacitor—resulting in high-pass filtering and limited low-frequency response—the 4115B offers a DC coupling mode that restores the sensor output to a true zero-volt baseline using a level-shifting summing amplifier.

This DC mode is ideal for applications requiring accurate low-frequency measurements, such as structural health monitoring or slow dynamic events. The unit includes a front panel “output zero” control via a 10-turn potentiometer, allowing precise voltage nulling. A built-in voltmeter and monitor switch enable real-time observation of either the sensor bias voltage or the conditioned output.

For added flexibility, the 4115B features an AC/DC coupling selector, making it suitable for environments where DC coupling may introduce thermal drift or instability. It can operate as a stand-alone desktop unit or be rack-mounted in Dytran’s 19-inch model 4200 rack adaptor, with space for up to 10 units thanks to its narrow 1.65-inch width.