DR7DC

The DR7DC is a single channel DC amplifier intended to provide variable excitation and signal amplification for strain gauge type transducers. It provides up to 10V output (or 4-20mA) with transducer signals from 10 mV to 10V. This allows operation with some high output transducers (DCTH, etc); for example, to provide 4-20mA outputs with signal inputs up to 10V.

This unit accepts both uni-polar (eg. 0 to 4mV) or bi-polar (eg +/-4mV) input signals and can produce corresponding uni-polar or bi-polar voltage outputs (ie 0 to 10V or +/-10V). Sensitivities and gains given in this document refer to both. Current outputs (4 to 20mA) are uni-polar.

The DR7DC incorporates a DC-DC converter ensuring that the output of the unit is electrically isolated from the supply.

The unit is housed in a DIN-rail mounting thermoplastics case with recessed screw-clamp terminals for all connections and 25-turn front-panel-accessible, zero and fine gain adjustments. There is also a front panel push switch and a facility to connect remotely an internal shunt calibration resister.

All other controls are internal including excitation coarse gain and switches to filter the output.