// Catalogue

Proportional Controlled Pumps: Electro Proportional Flow and Pressure Control

Proportional controlled pumps are variable pumps whose flow or pressure is set by an electrical signal, often from a PLC. TSA Hydraulics Engineering supplies them within the Servo & Control family of our Motors & Drives range, in piston and vane designs.

Before blaming the pump, put a meter on the signal. Many proportional pump faults turn out to be a broken connector, a tired amplifier card, or a 0 to 10 V signal feeding an input set for 4 to 20 mA. When the pump itself is worn, send the full pump and control code, and we will match a genuine pump or an equivalent, ready to leave Sydney.

// Buying guide

How Proportional Pump Control Works

A proportional solenoid on the pump’s control valve moves the swash plate or cam ring. The stronger the signal, the more flow or pressure the pump delivers. Common versions include:

Proportional flow control: the signal sets the displacement, so the pump delivers a set flow.
Proportional pressure control: the signal sets the maximum pressure.
p/Q control: flow and pressure are both set electrically, often with power limiting.
Closed loop control: a sensor on the swash plate reports its actual position, for higher accuracy.

Why Use a Proportional Pump?

Program different flows and pressures for each step of a machine cycle.
Replace several relief and flow control valves with one pump control.
Waste less energy, because the pump only makes what each step needs.
Get smooth starts and stops, with ramps set in the electronics.

Electronics and Signals

Proportional pumps need an amplifier to drive the solenoid. This can be:

Onboard electronics: built into the pump, taking a voltage or current command directly.
A separate amplifier card: mounted in the cabinet, with adjustable ramps and minimum and maximum settings.

Typical command signals are 0 to 10 V, plus or minus 10 V, or 4 to 20 mA. Note the settings on the old card before replacing anything.

Fault Finding

Measure the command signal at the pump or amplifier.
Check the solenoid coil resistance and the connector.
Confirm the amplifier settings haven’t been changed.
Check the pump’s pilot pressure and case drain.
Look for contamination in the control valve, which can make the response jumpy.

Proportional Controlled Pumps Specifications to Check

Pump type, displacement and maximum pressure
Control type: flow, pressure, p/Q or closed loop
Solenoid voltage and current
Command signal and electronics type
Response time and hysteresis
Flange, shaft and port details

Why Buy From TSA Hydraulics Engineering

As a proportional control pump supplier, we match the pump, the control valve and the electronics as a set, so the replacement responds just like the original. You get OEM or equivalent options, and help sourcing proportional controlled pumps replacement parts such as solenoids, amplifier cards and control valves. We tell you upfront whether a part is genuine or an equivalent.

// FAQs