Downsizing your shore power cord
Can you Substitute a 30-amp power cord for the original 50-amp one?
Hi Mike,
I enjoyed your talks at the Airstream International rally. And I just discovered our 50 amp power cord has a loose neutral plug and now has come out completely from the male end of the connector.
We have two air conditioners, but rarely use both. We are on the road for the next three months and wondered if we could replace the 50 amp cord with a 30 amp cord as long as we don’t use both air conditioners or too many appliances
simultaneously.
The reason why we want to do this is that a 30 amp power cord is so much easier handle and store. Is it OK to use a 30 amp cord with an adapter in our 50 amp airstream? Or would we potentially be compromising our electrical system ? Thanks - John
Dear John,
Yes this will work, but there a few important caveats. First, you need to purchase a short 30-amp to 50-amp dogbone adapter that will plug into the side of your trailer. I found this one on TechnoRV HERE.
Be aware that a 30 amp service has a lot less power
You may already know this, but a 50-amp service can supply up to 12,000-watts of power. While a 30-amp service only has 3,600-watts of power available. And yes, 50-amp shore power is actually 120/240-volts split-phase, but only the largest RV coaches actually use 240-volts. So your Airstream will operate perfectly on a single 120-volt/30-amp shore power connection.
Will this be safe?
Yes, the 30-amp circuit breaker in the campground pedestal should protect your new 30-amp shore power cord from too much current. So if you turn on too many appliances at the same time, all that should happen is the pedestal breaker would trip.
You’ll need to manually load-shed so as not to run out of power. That means turning on only one large RV appliance at a time. So you won’t be able to run your hair dryer, microwave oven, and A/C at the same time. For more info, read my full article on load shedding HERE.
Don’t plug this 30-amp power cord into a 50-amp outlet using a second 50/30 dogbone
However, if you do find that you’re tripping the 30-amp pedestal breaker, don’t be tempted to use a reverse 50-amp to 30-amp dogbone to plug your 30-amp power cord into a 50-amp pedestal outlet. That’s because the 50-amp main breaker in your RV’s load center would allow you to overload the 30-amp power cord and possibly start a fire. SO DON”T DO THIS!
Let’s play safe out there - Mike
50 amp power cords are so much heavier and less flexible than 30s. Trying to man-handle one can be quite a chore. Unable to afix a cord reel in a compartment that would allow easy deployment and retrieval, I store mine in a chest, tangle free, including the EMS and adaptors. I keep what I don't need in length rolled up in the chest and tucked under the RV. I still have to lift the chest however.
We have decided to stick with a 50 amp cord, but reduce it from 36 feet to 20 to 25 feet to help manage it better. Now I’m wondering if I should install a smart plug system when I cut the cord down. How easy is it to do it yourself? I installed two 100 amp lithium batteries and a converter this year and all is working perfectly. Appreciate any comments.