EHA-PID-201-A-20
by Vickers
The EHA-PID-201-A-20 module is a regulated DC power supply and signal conditioner manufactured by Vickers within the EHA Power Supplies series. It furnishes the low-level voltages and references needed for closed-loop motion hardware, while accepting command and feedback signals that coordinate proportional valves and other actuators in automated equipment.
Nominal operation requires a supply of 24 VDC, and at this input the unit draws only 6 W, minimizing panel heat. Command data enter through a differential demand port that accepts ±10 V and presents a high impedance of 100 kΩ, so upstream controllers are not loaded. A separate feed-forward channel also spans ±10 V but offers a lower impedance of 6 kΩ to improve noise immunity over short cable runs. Sensor feedback is handled either as a ±10 V voltage input with 1 MΩ impedance or as a current signal observed across a 100 Ω burden resistor. Positive and negative reference outputs deliver +10 V and –10 V at 10 mA each, providing stable excitation for potentiometers and displacement transducers.
Closed-loop drive signals leave the card through the PID stage, which can swing from ±10 V while sourcing up to 5 mA for direct valve modulation. Output accuracy is maintained by internal regulation that keeps residual ripple within ±10% pk of the commanded value. The electronics sit inside an enclosure rated IP20 under IEC 529, indicating finger-safe construction for mounting inside a protected cabinet. With isolated reference rails and a dedicated 5 mA PID channel, the module links seamlessly to external amplifiers, ensuring deterministic control without the need for auxiliary buffering.
