By Mike Sokol
Welcome to my J.A.M. (Just Ask Mike) Session, a weekly column where I answer your basic electrical questions. If you’re a newbie who’s never plugged in a shore power cord (or ask – what’s a shore power cord?), or wonder why your daughter’s hair dryer keeps tripping the circuit breaker, this column is for you. Send your questions to Mike Sokol at mike (at) noshockzone.org with the subject line – JAM.
Here’s a strange one for you. The RV breaker panel is in the bedroom. We occasionally hear a strange crackling noise coming from the panel when everything it turned off at bedtime. Do you have any idea how to figure out what’s doing it? Is this dangerous? —Eric and Kathleen
Dear Eric and Kathleen,
Great job on taking a video (with sound) of the problem. You can’t imagine how many questions I get that have nearly zero information. So this is a teachable moment for all my readers on how to gather information about a problem and where to get help on troubleshooting it.
Here’s the video you sent me, which is a great help. Watch the video in full size HERE. (Turn up the sound.)
First of all, this sounds more like relay contact chatter or possibly electrical arcing, so it’s something to take seriously and address immediately. What I would do is first turn off ALL electric power to the RV including unplugging from shore power, turning off any generator, and if you have a battery disconnect switch turn that off as well.
Next, open up the panel and look around for anything that shows black marks (carbon tracks) around any of the terminals or discoloration of any of the wiring insulation. That’s a sure sign that something is loose.
The final step should only be performed by an RV technician or electrician since it involves poking around in a live panel, and that could be deadly. But the basic process is to apply power to the RV with the panel open, and wiggle live wires around while watching and listening for any signs of electrical arcing.
But the best thing you can do is send this video to the panel manufacturer’s customer service desk and ask for help. Maybe they’ve seen this problem before and can offer advice. And if it’s under warranty they’ll be able to help you begin the replacement or repair process.
So what you all can learn from this is to document the problem with a video if possible. Go to the manufacturer or supplier of the product you’re having trouble with, and be as clear as possible as to what you’re observing. Don’t guess what may be wrong unless you’re an advanced troubleshooter like myself. However, if you do this long enough you’ll start to recognize failure patterns, and that’s when you’ll be able to apply your troubleshooting techniques to anything. And that’s really rewarding when it happens.
OK, everyone. Remember that electricity is a useful and powerful force, so we all need to pay attention to safety precautions while using it.
Let’s play safe out there….
Mike Sokol is an electrical and professional sound expert with 40+ years in the industry. His excellent book RV Electrical Safety is available at Amazon.com. For more info on Mike’s qualifications as an electrical expert, click here. Read more of Mike’s articles here.
I saw an advertisement for this product. It sounds too good to be true. Have you any experience with it?
Great advice on the circuit breaker panel.
Now, I need your help!! My problem is with my 12V system. When on shore power or generator, all systems work. Wipers wipe, mirrors adjust, EMS panel has full read-outs, water pump pumps, jacks go up and down, steps go in and out. Remove shore power and everything stops. I have a Xantrex Freedom 458 inverter that seems to be working. Been on several RV blogs that give lots of advice, but no solution. At my wits end! Oh, by the way, I replaced the two 12V chassis batteries, but this problem did not occur after that.
A good troubleshooting mindset can be applied to almost anything. Doesn’t matter if it’s electrical, mechanical, chemical or even biological. Learning how to observe the failure is one of the most important tools in your kit.
We had a problem in our Fleetwood Class A MH with a burning smell in the bedroom. I replaced 2 power outlets my wives blow dryer and the smell kept coming back. Finally I pulled up the cover over the water heater and found the insulation on the 120 vac going to the heating element burnt. Repaired the wiring and problem solved!!
I like your comment about not guessing what the problem is or trying to tell the tech what you think it is. I restore antique clocks and i almost always have to listen to several minutes of people telling me what’s wrong with it. The most common is “it’s wound to tight”. I zone out while they are talking. So offer the symptoms and leave it at that.
Definitely, agree Rob! I work on small engines and do the same when folks are telling me what’s wrong. I ask what have you done, so I know where to start looking for more problems.