Product Description:

The EEA-PAM-561-A-30 is a single-slot power amplifier card manufactured by Vickers for the EEA-PAM Power Amplifiers series. Designed for proportional valve control, it converts low-level command signals from a machine controller into regulated solenoid current so hydraulic actuators follow the desired setpoints. The card also furnishes auxiliary reference outputs and position feedback terminals, allowing closed-loop operation with LVDT position transducers and delivering precise flow or pressure modulation in automated presses, injection molding machines, and other industrial equipment.

It draws a control supply of 50 mA from the host rack and provides a stabilized output of ±15 VDC for external electronics. The enable circuit presents an input impedance of 22 kΩ; once the terminal sees at least 9.8 VDC the card is un-muted and the power stage activates. Internal dissipation is limited to 40 W, so forced-air convection is generally sufficient inside a standard panel. Reference signals of ±10 VDC at 5 mA are available to command proportional coils, while a solenoid current monitor outputs 1 V per amp for real-time diagnostics. Position feedback from an LVDT is buffered to ±10 VDC through a 10 kΩ monitor path, simplifying scope checks during setup.

The power stage is energized from a nominal bus of 24 VDC, and the design tolerates line excursions up to 40 VDC while shutting down gracefully below 18 VDC to prevent unpredictable valve motion. Incoming rail ripple can reach 10 % peak-to-peak without affecting closed-loop accuracy. Output current to the coils is slewed by an adjustable ramp generator; the user can limit acceleration to 5 s or sharpen response to 0.050 s depending on process needs. When the module is disabled, the reference path stays energized, allowing diagnostic signals to be monitored without energizing the valve.