Surge Protection Project

[Edward Buker]

I was wandering around Home Depot a couple of days ago, and being a person who loves a good sale, I found that they were closing out some Eaton Cutler Hammer whole house Surge Protection units.  This is the  $69 unit and if you find one in stock on closeout, at my local HD it rang up at $28. It has very good specs with high current capacity and a clamping rise time of less than a nanosecond which means as a surge comes in it passes it to ground about as quickly as they can engineer a unit to perform. It also has a $25K equipment warranty that I would not want to have to use but could help if you jumped through the expected hoops.

http://www.homedepot.com/Electrical-Breakers-Distribution-Load-Centers-Whole-House-Surge-Protectors/h_d1/N-5yc1vZbm05/R-202800798/h_d2/ProductDisplay?catalogId=10053&langId=-1&storeId=10051

Now this unit is not the all encompassing protection unit that disconnects the coach when the voltage is too low for safe operation of an air conditioner. This unit is for voltage spikes from lightning or electric motor inductuctive kickback that get in the power grid and raise havoc with electronic devices. If you generally use 50amp service in a campground rather than 30amp service then the low voltage issue is very rare and this unit will then offer good protection. If I was a person who used a lot of 30amp services I would install the Full Monty from Surge Guard. My perspective is if you have no protection at all at least consider this option for the minimal expense.

If you do an install as always be sure the coach is unplugged and the inverter is off.....then check again at our ages.

This unit could be installed at the main AC panel or in the bay at the transfer switch output side to the coach. I chose to mount this unit in the rear AC breaker panel so it would be easy to check the indicator lights from time to time. In my unit there is an unused DC panel that is included in the main AC panel in the rear closet. I chose to remove that DC panel and if you bend the mounting bracket back and forth a couple of times it comes out. I then used a step drill to open up a hole for the threaded connector on the Surge Unit and mounted it so the lights would be just behind the front panel. Mount the unit and connect the 4 wires, green to ground, white to neutral, black to 1/2 of the grid using a breaker screw connection (spare if you have one) and connect the red wire to the other 1/2 of the grid using another breaker screw. You can double up if need be on a used breaker. Every other breaker on a side alternates the side of the grid being used. That is a customary layout but if you do this project check your own layout by pulling a couple of breakers and see how the metal grid works that the breakers seat in. The most difficult part of this project is to get the surge unit lights to line up with holes that you drill in the face panel. That layout is a bit fussy. The whole project took about 2 hours. The labeled black breaker breaker cover is something I added so it may not appear exactly like yours. Hope this helps.

Later Ed

[Joel Weiss]

I agree that having some surge protection is better than none, but the "full up" units from SurgeGuard and Progressive do more than just shut off because of high and/or low voltage.  They also protect against incorrectly installed pedestals with floating neutrals, open neutrals, and reversed polarity.  From what I've read these conditions are not uncommon at campgrounds and can result in serious damage.   Floating and hot neutrals are conditions that can easily occur on 50A connections.  

I'm not in any way criticizing your effort, which appears to have been an excellent installation.  I simply wanted to clarify to ensure that people didn't make purchase decisions based on a misunderstanding the the capabilities of the different devices that are available.

[Edward Buker]

Joel,

That is a very good point and well taken. I was trying to be clear that this unit does not cover all the bases that the Surge Guard unit does but I did neglect to cover all the possible electrical issues one could run into that the other devices cover.

The two issues that seem like the most prevalent risks, based on my experience, are a low voltage condition (mostly on non 50amp service) and spikes from lightning strikes hitting the grid somewhere or spikes induced in the grid by electrical motor inductive kickback.

We live in lightning territory here in coastal Alabama and when home our coach is always plugged in. If I'm at home I will typically unplug the coach before a lightning storm and will continue to do so but you are not always available or awake when one occurs. For me the risk of a stray spike on a powerline was high and so that was my main reasoning for this minimal investment.

 Even if you have a Surgeguard installed this Eaton unit would be extra insurance. The joule rating is better on the Eaton device and the amp rating on the Surgeguard is 6500amps vs the Eaton is rated for 120,000amps both having a conduction rise time of less than a nanosecond. That just means that the Eaton can instantaneously pass a higher short duration current much better than the Surgeguard can. These devices can work together, having both online in your coach would not be a bad thing....

Later Ed