Product Description:

The EHH-AMP-702-J-20 is an electronic amplifier card manufactured by Vickers and supplied in the Vickers Accessories series. It converts low-power voltage references into controlled solenoid current for proportional hydraulic valves, letting a PLC modulate pressure or flow without separate drive hardware. By mounting directly on the valve body through a molded connector, the card shortens signal paths, minimizes conducted noise, and keeps the hydraulic package compact in industrial automation cells.

The unit runs from a nominal bus of 24 VDC and remains functional down to 20 VDC. It withstands excursions up to 40 VDC without overstressing internal components. While regulating the solenoid, its driver stage draws no more than 35 W and can source up to 1.6 A of load current, matching the coil requirements of most Vickers proportional valves. Internally, the amplifier uses a 10 VDC full-scale command range, provides a 10 V reference output for external potentiometers, and has a typical 1.5 V drop between supply and load so controller headroom is preserved. The supply line enters through an ISO 4400 (DIN 43650) connector that also carries the valve leads, and cable jackets up to 10 mm in diameter fit the strain relief.

An input impedance of 10 kΩ prevents loading of small-signal sources, while a built-in indicator LED lights at 200 mV to show logic power availability. The driver injects dither at 120 Hz to overcome spool friction and modulates the solenoid with a carrier of 1200 Hz PWM for smooth current resolution. Sealed housing and gaskets give the assembly an IP67 rating, so it tolerates washdown and oil spray between -20 °C and 70 °C ambient. This combination suits hydraulic valve installations that are exposed to moisture, oil, and routine industrial contamination.