The BBSI134 produces an isolated bipolar output signal from any type of input signal. Input signals can be bipolar or unipolar process signals such as -10 to +10V or 4 to 20mA. The output drive circuit is factory configured to provide load independent voltage or load independent bipolar current output. Maximum current drive for voltage output is 20mA at ±20V output. Applications requiring output >20mA up to 2A as is the case with hydraulic drive solenoids, can be accommodated using an external bipolar DC-power supply with a separate heat sink, carrying the drive transistors. Final calibration is trimmed using the front accessible OFFS and SPAN 15-turn trim adjustments. The output signal level is indicated by a green LED on the front, giving a clear indication of module function. All units are fitted with a 0.5 second filter. This filter constant can be increased or decreased if required. RF and power transient protection are with all BASI modules. Power supply isolation is achieved by the use of transformers for AC power and DC/DC converter for DC power.