The BSI239 is loop powered isolator used to measure DC voltages and process currents plus a range of optional inputs. Input/output isolation of 2kV rms is achieved by transformer coupling of power supply and signal. The BSI239 accepts a wide range of dc voltage and current input signals as well a supporting reverse and direct action mode at no extra cost. Standard output is 4-20mA with a minimum supply voltage of 8V. This enables the BSI239 to be used in 12V battery supply systems or in automotive applications. Other factory set output configurations are 10 – 50mA loop powered and 0 – 10mA, 0 -20mA or voltage output in 3-wire connection. Double surge protection is standard with all Series 200 loop powered transmitters to prevent failure due to spikes induced by DC switched inductive loads. Final calibration is trimmed using the front accessible zero and span 15-turn trim adjustments. A front mounted L.E.D. and a test socket verify module function and assist in calibration checks without disconnection of output wires.