EEA-EDC-436-A2-14 by Vickers

The EEA-EDC-436-A2-14 is a plug-in power amplifier card produced by Vickers for the EEA-PAM Power Amplifiers series. Mounted on a DIN rail or card rack beside the hydraulic manifold, the module accepts low-level process commands and delivers regulated coil current to proportional solenoid valves. By translating voltage or current references from a PLC into precise magnetic force, it lets an automation system modulate hydraulic pressure and flow without dedicated valve electronics.

During operation the card draws a maximum input power of 40 W from a nominal supply of 24 V DC. If the supply drops to 19 V DC or lower, an internal undervoltage latch disables the output to prevent unintended motion. The incoming rail must be filtered so ripple does not exceed 4 V pk-pk. Command processing is flexible: the voltage channel accepts up to 10 V and offers a 47 k? impedance, while the current channel works with industry-standard loop signals and presents a 100 ? load. Separate ±10 V reference outputs can each source 5 mA for external potentiometers, and an auxiliary +15 V terminal can provide 50 mA to small indicators or transducers. An enable line must reach 10 V before the amplifier responds to any command input.

With the amplifier enabled, the output stage supplies a bias of 1.4 A at zero command to overcome valve dead band and guarantee a predictable neutral position. Current-mode inputs can rise to 20 mA, giving full-span control from standard 4-20 mA transmitters. The factory ramp network limits command-to-current rise to 50 ms, smoothing small steps, and an onboard potentiometer allows that interval to be extended to a maximum of 2 s for large hydraulic cylinders. Keeping supply ripple within tolerance and maintaining adequate reference current helps preserve proportional accuracy throughout the duty cycle.