Inspecting Pushmatic Circuit Breakers
Pushmatic circuit breakers were introduced to the market in
the 1950’s. The original Pushmatic breakers were manufactured until the late
1960’s. The Pushmatic breakers are more of a large “button” style instead of
the more modern handle style circuit breakers. Before we address the actual inspection of
Pushmatic breakers, let’s examine the way the Pushmatic operates and is
constructed. Modern circuit breakers utilize a combination of a magnetic and thermal mechanism to interrupt the
circuit. This is a “belt & suspender” fail safe for the circuit. Early
Pushmatic breakers only had a thermal mechanism, providing only one method to
interrupt the circuit. I am unaware of any fires caused by these early
breakers. When inspecting an electric panel employing Pushmatic circuit
breakers, here are some of the items we should be looking for:
In addition to everything else we look for in an electric
panel, pay close attention to the position of the Pushmatic breaker. Pushmatic
breakers are bolted into the Main Service Panel not “snapped in” like modern
lever type breakers. Visually ensure that the breaker is not loose and pushed
completely down (if in the on position) or is completely up (if in the off
position). The early Pushmatic breakers may not be fully engaged because they
were lubricated and may be difficult to operate after several years. If you
look at the breaker when it is in the on position or pushed fully down, you
will see word “on”. If disengaged, or if the breaker is in the up position, the
words “off” will be visible. One of the other problems with the early Pushmatic
breakers is that they became stuck between off and on. This would pose a
quandary and safety issue for the homeowner or electrician working on a
circuit. Another problem experienced by the early Pushmatic’s is the ability to
reset. The breaker will not stay down or in the “on” position. If you see any
of these issues, the breaker should be replaced. Always recommend a qualified
electrician evaluate and upgrade as necessary. Newer Pushmatic replacements do
not have these problems and are safe. It also should be noted that replacement
Pushmatic breakers must be properly matched for the electric panel. Not all
replacements will fit all panels. Newer
Pushmatic replacements are quite expensive and it may be wise recommending that
your client upgrade the Main Service Panel with new modern style circuit
breakers.


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