Panel Mount Counter with Quadrature Input (Max Pulse Rate: 250 kHz, Diff. high/low thresholds: +/- 100 mV; Diff. common mode: +/- 1 V; Single-ended high voltage: 2.5 V to 10 V; Single-ended low voltage: -1 V to +1 V), Standard Input Power (85 – 264 VAC or 95 – 300 VDC), SSR Output (Two 120 mA), No Analog Output, RS-485 Communication. The PC-QD is a quadrature meter that accepts the A & B quadrature signals from linear encoders or shaft encoders to provide a highly accurate, scaled display of position, length, or angle in engineering units. The A & B quadrature signals are 90 degrees out of phase, and their phase relationship determines whether up counts (+) or down counts (-) are counted. The PC-QD meter totalizes the counts and then scales the total for display and control.