FPE circuit breakers and other brands often trip repeatedly when certain conditions are present. Many are quick to blame the circuit breaker or home electrical wiring, but a bit of investigation often shows the real cause to be user-related. If you have installed FPE circuit breakers yourself and notice recurring problems after installation, it's possible you didn't tighten them properly. You may need to shut off the power and have another look at your installation.
A related problem comes when using a new appliance. If you have installed a small refrigerator or air conditioner in a rec room or garage, you may notice tripping when using power tools or other motorized equipment. The FPE circuit breakers trip more often because the combination of the new appliance and the motorized equipment running at the same time is too much for your electrical system. You may need to turn off the air conditioner when running a vacuum cleaner, for example, or run the vacuum on an extension cord from another room. The fault is usually not with the FPE circuit breaker in these cases, even though it appears to be so.