Products > AC-PRO

AC-PRO® (Discontinued Product)

AC-PRO® End-Of-Life Announcement

The AC-PRO® Trip unit is a solid state, true RMS sensing overcurrent device for use on 600 volt class circuit breakers. The AC-PRO® comes standard with Long-Time, Short-Time, Instantaneous, Ground Fault, and Phase Unbalance protections. Each of these protective features can be turned on or off at any time except for the Long-Time setting. The units do not use ratings plugs and have a programmable CT rating. These features allow one unit to be used in a wide variety of different breakers. This simplifies the use, standardization, maintenance, training and spares situation throughout a facility. 

AC-PRO on a GE AK-25 BreakerAll of the interaction with the AC-PRO® is done through the front mounted backlit LCD and key panel. The settings for all of the functions are made in Amps and Seconds and are saved in non-volatile memory. In order to prevent accidental modification of the settings, the AC-PRO® has a security key that must be inserted in the top of the unit before changing settings. There is also an added security procedure that must be done before changing the CT rating.  Without the security key inserted, the AC-PRO® functions in a read-only mode. The last trip data, trip history and commissioning data can all be viewed, but nothing in the unit can be modified. 

When the AC-PRO® is in service it will display continuous 3-phase current monitoring on the LCD.  When the current exceeds the Long-Time pickup value the LCD will display OVERLOAD and list the phase and current, the red PICKUP LED will also illuminate. 

The green "SELF TEST OK" LED on the front of the unit indicates that the AC-PRO® is functioning properly. When the LED is illuminated it indicates that the software routines and microcontroller are functioning properly and the actuator is connected. 

During normal operation the AC-PRO® is powered by breaker mounted CT’s and will power up at 10% of the CT rating.  When there is no CT power the AC-PRO® can be powered by the PT Module, an auxiliary power pack or the internal battery. The internal battery is a 9 volt lithium type battery that is only used to power the display for reviewing trip data or commissioning the unit when there is no other power supply. 

The battery is not used for any of the protective features or to save any of the information on the unit.

AC-PRO Trip UnitThe AC-PRO® is designed to be used in wide range of rugged environments. The entire unit is housed in an extruded aluminum housing, the circuit boards are conformally coated and the keypad is covered in a contamination resistant membrane. Every AC-PRO® is tested under load and at elevated temperature for 24 hours before being released. None of the units are batch tested.

The AC-PRO® can be supplied as part of a complete retrofit kit. The kits include everything you would need to completely retrofit a breaker (brackets, mounting hardware, wiring, actuators, CT’s, installation documentation and instruction manuals).

All AC-PRO®’s are covered by a 2 year limited warranty

AC-PRO retrofit kit for G.E. AK-2-25The following options and accessories are available for the AC-PRO®

  • QT Display remote access unit
  • Secondary injection test set
  • 50Hz, 40Hz and 25Hz units are available
  • 1 amp and ½ amp units are available


Add-on options of Voltage Monitoring and MODBUS Communications for AC-PRO® are no longer part of our standard offering. If these functions are required, our suggested solution is AC-PRO-II® or AC-PRO-II® with VDM.

The AC-PRO® also has the QUICK-TRIP® arc flash reduction system available.

The QUICK-TRIP® system helps reduce the arc flash hazard on downstream equipment for times when personal must work on energized equipment. The QUICK-TRIP® system can be turned on and off without opening the cubicle door and features:

  • QT-Instantaneous setting
  • QT-Ground Fault setting
  • Door mounted switch with lockable cover or KIRK Key switch
  • Door mounted QT-DISPLAY with LCD display

AC-PRO® Variations

UL and CE Certification CE Label

To ensure that the AC-PRO® will function when needed it was tested to the ANSI C.37.59 Standards for fault interruption. As a result of this testing the AC-PRO® is UL listed on the following breakers.


AC-PRO® UL Listings
Manufacturer Breaker Model Breaker Rating
General Electric AK-2-50 1600A
General Electric AK-2-75 3000A
ITE K-1600 1600A
ITE K-600 600A
ITE K-800 800A
ITE KB Steel Back 600A
Schneider Electric Series H-3 800A to 4000A
Westinghouse DB-50 1600A
Westinghouse DS-206 800A
Westinghouse DS-416 1600A
Westinghouse DS-632 3200A

The AC-PRO® was tested & is certified to withstand radio frequency interference per the ANSI C37.90.2 Standard

ISO 9001

Product Fliers

AC-PRO® Product Flier

QUICK-TRIP®For AC-PRO® Product Flier

Instruction Manuals

AC-PRO® Instruction Manual

AC-PRO® Secondary Injection Test Set Manual


Replacing the AC-PRO® Battery and
Battery Cover

AC-PRO® Basic Information

Programming the AC-PRO®

AC-PRO® Battery Replacement (without battery cover)