The PD121 is a 4-wire signal conditioner with common process signal input and a controlled high current output. One terminal of the load is connected to supply negative.

• If wanting a controlled voltage output then use a PD122
• If wanting an isolated input, a controlled current output and the output load is fully independent of the power supply then use a PD122.

FEATURES

• High Power Output for applications where an output drive of 100mA (24V) up to 2Adc is required, as is common with hydraulic solenoid drive applications.
• Signal conversion from all commonly used process control signals.
• Signal inversion for applications where the output has to decrease for increasing input (Reverse action).
• Signal filtering for fluctuating input signals. The "Ramp option" allows for the time constant to be selected by the user.
• Gain and bias (scaling) adjustments to amplify or zero shift a portion of the input signal.
• Dither option. A low level AC signal is superimposed on the output to prevent the output valve or hydraulic solenoid from becoming stuck in applications where the valve is stationary for long periods of time (the amplitude and frequency of the dither signal are specified for the application)