30-Amp Twist-lock Upgrade!

Why do they fail? And is there a better solution? (Jan 2024)

I just answered this on the RV Lifestyle Group…

Hey Beth,

You need to replace both sides of the connector as otheres have already noted. You can get a replacement kit on Amazon for around $30 HERE.

I’ve been doing lab tests of L5-30 and TT-30 connector meltdowns, and the primary reasons for failure seem to be oxidation of the contacts, as well as not twist-locking the plug and using the locking ring.

History of the twist-lock connector

The RV 30-amp twist lock connector was not originally designed for use outside on a vertical surface. It was a Hubble connector patented in 1938 used for overhead power connections of portable equipment in factories. The locking ring was added by the RV industry to provide extra support to help eliminate the connector flexing from the weight of the cord which reduced the contact area, as well as stop rainwater from getting inside and oxidizing the contacts.

Make sure you twist it to lock it

I’ve taught seminars on RV hookups many times and usually find a few RV owners who didn’t know that you needed to twist the plug to lock it in place, or who don’t bother using the locking ring. Both will cause connector meltdown at relatively low currents.

I also recommend the seasonal use of a good contact cleaner to remove oxidation. DeoxIT D5 is the best contact cleaner and anti-oxidant I’ve ever used. Get it on Amazon HERE.

Here’s a better answer from that same thread

Where to buy SmartPlugs (and lots of other RV stuff).

I’ve recently started an affiliate program with TechnoRV which does pay me a small commission on products that you purchase from them. I’ve know Eric and Tami for years, and their customer service and educational programs are fantastic. That’s something you don’t get from Amazon or eBay (as much as I like both of them). So click the TechnoRV logo above and take a look around. Many of their products were independently reviewed by me before they became dealers for them. For a direct link click HERE.

FYI: I did a 50,000 cycle insertion test with 30 and 50-amp SmartPlugs in my FunkWorks Lab last year, and they were still working perfectly.

Wait, there’s MORE!

Read my previous article on why 30-amp Twist-Lock plugs melt down HERE.

Some of the products above have affiliate links. This means that, at zero cost to you, I will earn a commission if you click through the link and finalize a purchase. But feel free to find your best deal anywhere you like.

Let’s play safe out there… Mike