Brute Force Electrical Diagnostics
A systematic approach to finding failed components is a more definitive way to troubleshoot electrical problems with appliances. I recommend using the LoZ function of your multimeter if you have it. Below are point-to-point voltage drop testing methodologies for both 240v and 120v appliances.
240v Point-to-Point™ Voltage Testing
120v Point-2-Point™ Voltage Testing
Below is the methodology and checklist for 120v appliances. I recommend using the LoZ function of your multimeter if you have it. A voltage pen can be substituted in some cases for the voltmeter. You would simply be checking for the presence of 120v at each point in the circuit.
Point-2-Point™ Voltage Pen Diagnostics
Click the picture below to purchase our recommended voltage pen.
A voltage pen (non-contact) voltage tester can also be used for point-to-point voltage drop testing. It is less accurate, but can give you a “go” or “no-go” sense of what is happening in a circuit. Below is a method for troubleshooting 120v circuits such as dryer motors, defrost systems, and gas dryer circuits, using a voltage pen. Note that a voltage pen is not appropriate for point-to-point 240v troubleshooting since L1 and L2 will both trigger the pen – and you will be unable to discern between the two. It would be the “multimeter” equivalent of referencing neutral or ground in a 240v diagnosis, which is not advisable.
Recommended LoZ Meter
The Klein CL800 is a great all-around meter for field techs. It is comprehensive – including just about every feature you’d want in the field, including LoZ testing for AC and DC volts. Producing and writing such articles takes much time. I do make a commission of of any sales purchased through the following link, and I do appreciate your support. CLICK HERE FOR THE KLEIN CL800 (OR CLICK THE IMAGE BELOW)
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