The BFRT287 is a isolating transmitter that accepts a variety of frequency or pulse input signals. Typical inputs include signals from turbine flow meters, NAMUR proximity sensors, or any device producing a DC pulse or pulsing contact. Frequency range is 5Hz up to 5kHz with an amplitude range of 0.2Vp-p up to 50V pulses. The input conditioning consists of a charge-pump circuit, converting pulse signals produced by a front trigger circuit to an analogue signal. The measured input is then scaled by an isolating transmitter with a link selectable output providing true three way input/output/supply isolation up to 2000V. Final calibration is trimmed using the front accessible zero and span 15-turn trim adjustments and a link selectable output range. A wide range ac/dc supply powers the input and the output circuits.