The Mag Switch on a Cabinet Saw Is Overheating

Heater Control

• Table saws often have a heater control dial that works much like a circuit breaker. If the operating temperature of the saw reaches a certain level, the mag switch will trip and will shut down the saw. The heater control dial has numbers, usually between 10 and 17, and can be turned to a higher value to increase the temperature limit.

Sensitivity Screw

• A small screw located on the mag switch controls the sensitivity levels of the off switch. Turn the screw on the mag switch to see if the saw turns off automatically. Rotate the screw to decrease the sensitivity of the screw and try pressing in the switch again. If the saw does not turn off until the switch is pressed about ¼ inch, the correct sensitivity has been reached and the switch should not overheat or shut down so quickly.

Dirt and Dust

• Since the saw typically is a woodworking machine, the sawdust and dirt can collect on the mag switch over time, causing interference and overheating. Disconnect power to the saw and clean out the switch using a can of compressed air. Then reconnect the power and try the saw again.

Overheating Motor

• The motor on the saw also may overheat, causing the mag switch to overheat and shut down the machine. Let the saw cool down completely and then disconnect the power before cleaning sawdust from the saw motor, duct and fan. Slow down the feed rate when you reconnect the power to help reduce overloading.