Replace Your Masterpact M Trip Unit and Save Money

August 3rd, 2015

Breakers last for years; it’s trip units that need attention. Changing the breaker because components like a Masterpact M trip unit isn’t supported any more wastes time and money.

ComAp’s AMP-SAFE PRO is direct replacement for Masterpact M trip units. It extends the life of installed breakers, reduces maintenance time and slashes parts costs.

The AMP-SAFE PRO is the only UL and CE-listed replacement for STR trip units. It extends the serviceable life of a circuit breaker without the expense or downtime associated with a full refurbishment.

Schneider Electric discontinued support for the Masterpact M trip unit in 2014. The company promotes an entirely new circuit breaker when existing trip units fail. This is expensive, disruptive and unnecessary.

With the AMP-SAFE PRO, a circuit breaker can be restored to full working condition in less than twenty minutes.

Save money, save time

The money saved by replacing a trip unit instead of the Masterpact M circuit breaker is far from trivial. New circuit breakers cost anywhere upwards of £30,000. That’s roughly ten times more than a new AMP-SAFE PRO trip unit.

And that’s before you even think about the time taken to replace the circuit breaker. The AMP-SAFE PRO Masterpact M trip unit takes less than twenty minutes to replace. Commissioning a new circuit breaker can take more than a man-day.

Engineering time is not your only consideration. When a circuit breaker is down for maintenance there are knock-on effects for other parts of your business. A 20-minute disruption is easy to work around; it’s not so convenient if the disruption last for more than a day.




The AMP-SAFE PRO is compatible with Merlin Gerin & Square D Masterpact M trip unit, IEC or UL-rated circuit breakers as well as Klockner Moeller IZM models that use a XZMA type protection unit.


The AMP-SAFE PRO can be user-programmed to replace STR-18M, 28D, 38S or 58U trip units.

Technical accuracy

The AMP-SAFE PRO has the same protective functions, settings and time-current curves as the original STR.

If you want to know more about how the AMP-SAFE PRO can help you, call Ian Wassman on 07767 112262 or email him at