” I just bought my RV 4 weeks ago and tried to hook up at home the night before my first trip and had a problem. I backed my RV near the house, used my 50ft. (30Amp) cord, and I got shore power from my home no problem. The A/C worked and all my electrical stuff as well.
When I park in the street (commonly happens), I need 75ft. of cord. So I bought a 2nd 50ft (30Amp) cord and surprisingly, it does not work! “
Great question! There are two big reasons why this may be happening.
The first reason might be that you have now ran too (Long) of a chain of cords. When power cords are daisy chained too long, you will see a drop in voltage, and thus not enough power to the A/C Unit. Or the power cord itself may be defective. To test if your cord is defective you can use an OHM Meter and check each leg for continuity. We have a great guide on how to do most cords in our article: Testing your rv / generator power cords. You can also try plugging in a cord you know does work and see if you can get power from that one.
If your cord isn’t defective, you may be running too long of a cord and are losing voltage over the span. There’s a more detailed explanation in a post we did explaining the basics of voltage drop and why it happens here: Power Cords & Voltage Drop.