Product Description:

The EEA-PAM-571-D-32 is a plug-in power amplifier card produced by Vickers as part of the EEA-PAM Power Amplifiers series. It supplies coil current, ramps command signals, and processes transducer feedback so proportional valves can track electrical references in pressure, position, or flow control loops found in automated presses, injection machines, and test rigs.

The board is energized from a regulated 24 VDC source and offers ±10 V reference outputs that each deliver 5 mA for external set-point potentiometers. A voltage command channel loads the driving controller with 47 kΩ, while the alternative current command path presents 100 Ω. The internal ramp generator accepts triggers through a 10 kΩ input, and its analog output may feed loads down to 10 kΩ without distortion. For position feedback, the card furnishes a stabilized 15 VDC supply for an LVDT, and the monitor point allows diagnostic measurement through a 10 kΩ path. Sensor inputs are matched to the process being measured: the current interface repeats the 100 Ω figure used on the command side, whereas the voltage interface offers a high 1 MΩ load so delicate probes are not burdened.

An alarm transistor can sink up to 50 mA and includes 50 Ω of series resistance to limit fault-loop currents. Feed-forward action is brought in through a dedicated path that is terminated with 6 kΩ, letting rapid spool shifts bypass the slower closed loop when necessary. The ramp output must not drive less than 5 kΩ to retain its calibrated slew rate, and the voltage sensor input’s very high impedance of 1 MΩ guards against loading low-energy transducers. A separate drive-zero indicator, also set at 50 Ω, enables coil neutral adjustment while the circuit is active, completing the impedance network that keeps signal integrity and valve dynamics consistent across all operating modes.