Forum Discussion

rbpru's avatar
rbpru
Explorer II
May 02, 2021

Surge protectors and Joules

I have been reading about surge protectors and the consensus seems to be the surge protector should have about 1000 Joules minimum and more is better. I have seem some units in excess of 4000 Joules.

I understand how useful a line conditioner can be to prevent over or under voltage, and even my cheap little Camco has detected cross wiring issues.

However, my question is where are you going to get a surge on the line from?

I know lightening strikes will induce an inductive kick on the line but a lighting volt has about 1 billion joules; what percentage of that will reach you RV would seem to be a matter of luck.
  • I must admit when I see the increased numbers of electronic devices in RV use today, a good energy management system seem appropriate.

    Fortunately, my 10 year old TT has none of that. The water heater, fans, 12 volt converter, and the world cheapest OEM TV and Microwave are the only 120 volt systems in use.

    Proper voltage to the AC could be an issue. However, my wife does not like it so it is rarely used.

    So far my biggest issue was incorrect wiring. It was at a State Park. We chose another spot.
  • rbpru,

    Your question illustrates why a surge only device is not terribly useful.

    Upgrade to an energy management system. Far more damage to motors is from low voltage.

    I do have simple surge--but much prefer the autoformer which "fixes" low voltage.

    I also limit my demand to 80% of the available supply, and use load support on the Magnum inverter charger.

    My first surge device did "burn out" and I suspect (but am not certain) it failed in a campground in summer time on a hot day.
  • Certainly possible to get a surge in a CG with RVs plugging/unplugging with high amp appliances turned on. CG equipment and CG maintenance is to often marginal. Plus utility company issues.

    My PI HW50C unit has never indicated a surge in 17 years so if one occurred it was less than the rating. But I've had various other electrical faults which is why I have a EMS unit. Low voltage occurs to often. Had 160V one time. Reverse polarity several times.

    I would not want a surge only unit vs a EMS unit. Yes they cost more...
  • Other than lightening I would think that large inductive loads starting and stopping would be most likely to produce a surge. If you're in a small rural campground it's probably less of an issue then if you're in a campground closer to large industry that may have large motors. Campgrounds near amusement parks and water parks would likely be more susceptible to spikes form all the ride and pump motors.
    However, some campgrounds may have some rather large motors on pool pumps, well pump, sewer treatment pumps, etc.