This card is designed for pressure controlled servo pumps. It manages closed loop control of pressure reducing and pressure relief valves.
The card works as a bypass control module. The command value is directly transferred to the control output (pressure valve) and the closed loop compensates only the linearity failures. In most of cases the optimization is possible without any measuring instruments (a pressure sensor is necessary only).
It has an integral power amplifier for direct control of proportional valves.
Card setup via software only, through an on-board USB-B port. Customizable parameters are: ramp up, ramp down, PID parameters, dither, frequency and amplitude, PWM, maximum and minimum pressure.
The EWM-PQ-AA has been developed as a classic p/Q controller but it work well also with high response valves via an analogue command input for pressure and flow.
The p/Q controller automatically switches between Q and p control modes to assure that the set point limits for P has not to exceed.
The pressure feedback is analogue type.
The card use the RS232C interface, and is settable via notebook, using the software kit EWMPC.