Testing an RV / Generator Power Cord

Note: This guide only covers most 15, 20, 30, and some 50A power cord / adapter applications. 4-Wire, 4-Pole applications are different and will be covered in another article!

Many of you have made your own RV / generator power cord or adapter using assembly ends like these, and just want to make sure that you have done a good job before you use them. For this example let’s assume I am wiring an RV, 30A to 15A adapter like this finished example.

What we want to do is make sure each wire was connected to the proper terminals on each side of your cord and the right color wires! Like this example below:


A 30A, 3-Wire adapter cord. Showing what wires lead to where.

First, you want to buy a Multimeter. I am starting with a pre-made ROJ adapter from Conntek. And want to test it to make sure that it is wired properly, and to find the right wires to connect.


A multimeter next to a DIY 30A adapter made by us. Ready to begin testing.

Now that you have everything all set up. Start your multimeter by turning the center dial to the “Alarm,” setting circled in red. This setting will make a noise when you place the meters’ probes are touching the same wire.

Setting your multimeter to alarm setting to test your power cord

Make sure your meter is set to “Alarm,” mode and set it back down. You are ready to test your cord.

Now that we know a little more about what we are doing, it’s time to start testing.

Our first test is for the ground pin, “Green.”. We stuck a pin into the round opening (most common shape for ground pin), got a beeping noise, and a small reading. We know that our current end is wired properly to the right wire.

Now you know what wire to run to your ground terminal of the other side!

Testing the ground pin of an rv generator power cord

Put one probe into the ground pin and find the corresponding wire. It should run to the “Green,” jacketed wire.

We wanted to make sure our Neutral wire, or “White,” was wired correctly. We stuck a probe into the lower pin and to the white wire, resulting in a beep / reading.

Good! We found our neutral wire.

DSC_0032 (1024x678)

All you have left is to check the last wire. If all goes well, it should be the black Live “Black,” opening to the black wire. Now you are ready to wire the other side of your 3-pole cord.

Tagged with: ,
Posted in DIY, Generator, RV

Have a comment? Leave it here!

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s

Follow Conntek Power Solutions Blog on WordPress.com