How To Use A Voltage Meter. To test your power supply you first need to set the multimeter to volts AC. Multimeter to the rescue.
First get a paper clip and bend it into a U position. Using one hand insert a probe into each vertical slot on the outlet. Then measure dc voltage by selecting a dc voltage range using the RANGE button that is the same or higher than the ac voltage range.
Test switches outlets and power cables to see if there are any problems.
To ensure maximum accuracy of a dc voltage measurement first measure and record the ac voltage. Use a multimeter in your HVAC unit to make sure the compressor is getting the right amount of electrical power. Connect the black probe to the common jack on the multimeter. Then measure dc voltage by selecting a dc voltage range using the RANGE button that is the same or higher than the ac voltage range.
