How to Check Capacitors Using an Ohmmeter
Disconnect the power source of the capacitor., Use masking tape to label the wires that connect to your capacitor., Pull off the terminal connectors of the wire away from the wire terminals of the capacitor., Take a screwdriver that has an insulated...
Step-by-Step Guide
-
Step 1: Disconnect the power source of the capacitor.
You should also make sure that the device which the capacitor powers is unplugged before your continue.
If the appliance is instead hard wired, simply turn the circuit breaker off. -
Step 2: Use masking tape to label the wires that connect to your capacitor.
In some cases you will see terminal labels that have been printed on the housing or lid of the capacitor.
Capacitors which don’t have such labels don’t need them because they are non-polarized. , You can use needle-nose pliers to make this easier.
Use the pliers to terminal connector off the terminal.
Make sure you don’t use the pliers to pull on the wire. , Make sure the metal of the screwdriver is touching the two terminals – this will discharge your capacitor.
In case you want to test a dual capacitor, make sure to hold the screwdriver on the “COM” labelled terminal.
Then use the screwdriver to independently touch the other terminals. , Take its two leads and touch them together in order to zero the meter. , In case your capacitor is polarized, then you have to put the black lead on its negative terminal.
In case it is a dual capacitor that you are testing, put the black lead on its “COM” terminal. , Take a look at the reading of the ohmmeter.
If the needle goes to infinite, then retreats a little bit and moves back to infinite again, then the capacitor has passed the test.
The capacitor will not pass the test if the needle goes to infinite and then stays there or if the needle doesn’t move at all. -
Step 3: Pull off the terminal connectors of the wire away from the wire terminals of the capacitor.
-
Step 4: Take a screwdriver that has an insulated handle and put it across the terminals of the capacitor.
-
Step 5: Take your analogue ohmmeter and turn it to the highest setting.
-
Step 6: Take the black (negative) lead of your ohmmeter and put it on a terminal of the capacitor.
-
Step 7: Take the other lead (positive) of your ohmmeter and put it on the remaining terminal of the capacitor.
Detailed Guide
You should also make sure that the device which the capacitor powers is unplugged before your continue.
If the appliance is instead hard wired, simply turn the circuit breaker off.
In some cases you will see terminal labels that have been printed on the housing or lid of the capacitor.
Capacitors which don’t have such labels don’t need them because they are non-polarized. , You can use needle-nose pliers to make this easier.
Use the pliers to terminal connector off the terminal.
Make sure you don’t use the pliers to pull on the wire. , Make sure the metal of the screwdriver is touching the two terminals – this will discharge your capacitor.
In case you want to test a dual capacitor, make sure to hold the screwdriver on the “COM” labelled terminal.
Then use the screwdriver to independently touch the other terminals. , Take its two leads and touch them together in order to zero the meter. , In case your capacitor is polarized, then you have to put the black lead on its negative terminal.
In case it is a dual capacitor that you are testing, put the black lead on its “COM” terminal. , Take a look at the reading of the ohmmeter.
If the needle goes to infinite, then retreats a little bit and moves back to infinite again, then the capacitor has passed the test.
The capacitor will not pass the test if the needle goes to infinite and then stays there or if the needle doesn’t move at all.
About the Author
Sharon Cole
Writer and educator with a focus on practical cooking knowledge.
Rate This Guide
How helpful was this guide? Click to rate: