EPC Servo Controller

EPC Basics

EPC is an acronym for Electronic Pump Controller. However it is much more than a simple pump controller. The EPC Servo Amplifier Module is a micro controller-operated component that can be applied to operate servo or proportionally operated pumps and valves. Because of it's onboard microprocessor this unit can perform many additional functions that your typical Servo Amplifier can not. The unit can be configured for several types of control applications including:

  • Flow Control
  • Flow Control with Pressure Limit
  • Flow Control with System Horse Power Limit
  • Pressure Control
  • Pressure Control with Flow Preset
  • Closed Loop Speed Control
  • Load Sense Control
EPC Specifics

The EPC allows for a single control axis with a power amplifier to drive most servo valves, pumps, and proportional valves. The basic pump controller configuration allows for fast (up to a 1600Hz) closed loop response with both stroke position and pressure feedback. In addition, two independent function programs can be dynamically selected with a digital input signal. The unit also provides a digital output for simple diagnostics or a watchdog signal.

Three general-purpose analog inputs are provided for command and pressure feedback signals in either ±10 VDC, 0-to-20mA, or 4-to-20mA format. Additionally, one analog input is provided as a dedicated fine-adjustable LVDT stroke feedback device. The module allows for two low-power programmable diagnostic analog output voltage signals.

Click for a printable copyThe EPC is configured by first assigning one of twelve built-in function programs to one or both of the program blocks. Typically, the output of the function programs is then passed to the Pump Controller, which provides the valve drive current.

If the full features of the module are used, up to three (3) independent closed loop PI (Proportional with Integral) control algorithms are utilized. Most function programs provide a closed loop control algorithm for pressure or stroke, while the Pump Controller can be configured for both stroke and power feedback.