RV Electricity – Can I add a second surge protector?
Dear Mike, Thanks for your No Shock Zone articles! I am a big fan. I have a technical question based on an issue raised by a fellow camper. I have a Progressive Industries Surge Protector (EMS-HW50C Portable Electrical Management System) on my 50A diesel pusher, and I also use a Camco Dogbone RV Circuit Analyzer with integrated surge protection and fault indication (125/250V 50M/50F Amp) for use at the pedestals.
I got the Camco circuit analyzer primarily as a way to monitor the quality and safety of the power of the pedestal, but the unit also provides surge protection. I’ve had a fellow camper suggest that putting a second surge protector on the pedestal is a bad idea, since I already have a surge protector on the rig. Is putting a second surge protector at the pedestal okay, or a bad idea? —Michael C.
Dear Michael, Actually, it’s a very GOOD idea. You’re adding additional joules of surge protection at the pedestal, which will also help keep lightning spikes out of the inside of your RV. Plus you can use the portable surge protector to do a preliminary check of the campground power BEFORE you accept the campsite….
However, for any of you who don’t have an intelligent/EMS surge protector like your EMS-HW50C which checks for high and low voltage as well as open grounds, let me suggest that instead of something like a basic Camco circuit analyzer, you get an intelligent surge protector for the pedestal such as the Surge Guard 34950 (50-amp) or 34930 (30-amp) unit. This will not only increase the joules of spike protection due to the extra MOV devices, it will add downstream open-neutral testing and shutdown on the 50-amp version.
As a power precheck before-making-camp procedure (before you pull in your RV, level it and connect up the water, etc.), I’m recommending that everyone first use a NCVT (Non Contact Voltage Tester) such as the Southwire 40116N to check the campsite pedestal to make sure the box itself doesn’t have a stray voltage. (Yes, I’ve had several emails in the last month with this really dangerous condition.)
If the pedestal does have a stray voltage, DO NOT accept the campsite and move on. If it’s OK (shows no voltage on the outside of the pedestal box), then plug in your intelligent surge protector and check the outlet for open ground, reversed polarity and reasonable voltages (102 to 132 is considered acceptable, but I think a range of 105 to 128 is safer). If the voltage is a little low you might be OK using this pedestal as long as you don’t run hot plates and air conditioners. And if the polarity is reversed you’re still probably safe, but the campground should be notified and repair the problem quickly.
However, if the outlet ground is open, then DO NOT accept the campsite and ask to move to another one after notifying the campground of the problem. Bypassing your surge protector on a pedestal that has an open or hot ground is putting your life and the lives of anyone else touching your RV in danger, so please take this seriously.
Next week I’m going to post a cleaning procedure for any campground pedestals that were in the flood path of Hurricane Florence. No, you can’t just wait for the outlet to dry out and plug in. Any pedestal that’s been underwater needs to be properly cleaned and tested before being put back into service.
Let’s play safe out there….
Mike Sokol is an electrical and professional sound expert with 40 years in the industry. Visit NoShockZone.org for more electrical safety tips. His excellent book RV Electrical Safety is available at Amazon.com. For more info on Mike’s qualifications as an electrical expert, click here.