Power Surges vs 12v adapters...what happened? HELP?

[crazyred75]

I have my 5th wheel plugged into a 50 amp Surge Guard and all of my electronics such as computers/tv's and other items plugged into a separate power-surge strips inside the RV.
Well, the other day there was a MAJOR power surge that took out our Surge Guard and the 50amp Power Cord....melted both....Thank God I listened to the RV Maintenance man when I bought the RV to spend the $$ on one cause it is an investment. It not only saved the RV, but the Truck parked next to it and my cat inside. 🙂
So, after all that was said and done, and replaced, I noticed that two out of three items plugged into the inside surge protector power strip were dead. My laptop was fine, but the other two electronics were not working. Found another item today that was plugged straight into the wall that was dead as well.
I bought new 12v ac universal adapters to replace them, and now they work again but I am still confused, what happened to the adapters?
Why would they go out when my RV is suppose to be "protected"?

[crazyred75]

I will make sure I do that. Yea it was pretty bad, but this is the reason I paid for the "protection". Better the replaceable adapters then the Cat. 🙂 The 5th wheel could be replaced through Insurance, but not the cat and other replaceable items. I suggest to anyone to pay for the added insurance just in case.

[beemerphile1]

crazyred75 wrote:
12V adapters that I am referring to are the items such has a XM Radio and a Neck Massage device that had removable adapters/chargers. They were plugged into a surge protector. Other hardwired items such as speakers, or the toaster were fine.
Maybe I am not explaining it properly, but I read what was on the back of the adapter.

Thanks, presumably these are plugged into 120vac and not 12vdc. Anything plugged into 12vdc shouldn't be affected.

My XM radio operates on 6vdc and has adapters to plug into 12vdc or 120vac.

What you had damaged are what many people refer to as 'wall warts' which convert 120vac to whatever power is needed for the appliance. I think correctly they are a 'power supply'.

To avoid this issue in the future I would suggest that anything capable of operating on 12vdc be connected to 12vdc. The converter/battery then provides some protection from damage.

Like many have said, you probably experienced an open ground allowing 240v to be supplied to your 120v items.

[crazyred75]

12V adapters that I am referring to are the items such has a XM Radio and a Neck Massage device that had removable adapters/chargers. They were plugged into a surge protector. Other hardwired items such as speakers, or the toaster were fine.
Maybe I am not explaining it properly, but I read what was on the back of the adapter.

[traveylin]

The above referenced RV Electrical nails the topic. The imbedded article regards open neutral beautifully described why a high voltage occurrence can happen even with the additional protection available to rvers for 50 amp service. My take away message is for one who moves frequently, using the 30 amp service is preferred if the rv usage is low enough to support. Load testing may be useful for semipermanent installations but it would slow down the set up/takedown time for a traveler.
His other topics are very informative.

pops

[beemerphile1]

Could you describe exactly what you mean by "12v adapter"? Everything I use that operates on 12v gets plugged directly into the 12v system. The 120v items get plugged into the 120v system.

[SteveRuff]

Last summer I had my Progressive SSP50 plugged into the 50 amp plug and my motor home plugged into that. I experienced a brown out in the middle of the night. This happened several times finally ending with no power coming into the motor home. The next morning I was able to see the 50 amp plug was fried, the surge protector was fried, and the prongs on my cord showed discoloration. Luckily, nothing inside seemed to have been harmed. All systems worked on batteries and when I switched to the 30 amp plug everything worked as usual. We left the park, with no replacement or even much of an apology and only discovered several days later that our Splendide Combo was dead. It has it's own built in surge protector and that was fried as well as the motherboard. This was almost a $1000 lesson adding a new plug, new surge protector, and WD repair. I replaced the surge protector immediately. Oddly enough, this had been a Christmas present and I had just started using it on a regular basis. 6 years without one with no problems, 6 months with one and it saved my coach ...go figure.

[Larryect]

There is a lot of good information on this web site: RV Electric

Look at the section called "open Neutral" and it explains how an open neutral can cause high voltage to the coach.

[chrisncary]

This thread is great information, and scary as hell...

[crazyred75]

I also realized that the electrical devices that had hardwired 12v plugs such as the speakers, Bissell hand vacuum and toaster, were fine. It was just the 12v adapters that were removable that fried.
It is defiantly a learning experience.
Thanks again all for your input!

[Larryect]

Yea. It would be really hard to figure out what the exact dynamics were. It could be the trencher cut the neutral, and or ground wires first. Or at least before the hot legs were severed. And some how a higher than normal voltage was injected into the coach. Also and arc flash can create huge spikes to be on the line.

Surge protectors generally work by shunting the spike to the ground wire. If the ground wire was cut, it couldn't do that.

And apparently it wasn't quite fast enough in shutting the power down. It needed to decide to drop the relay and then the relay needs time to physically open and break the connection. It is VERY quick, but in this instance just not quick enough to save everything. On powering up the coach it can take it's time analyzing the power before engaging.

Bottom line - the 12 volt adapters probably have some small diodes or something that was more sensitive and burned up quicker than the EMS responded. My best guess is some of the spike voltage got through because it was more than the shunt device could handle, or there was no place to shunt it too remaining. The cutting of the cable, most likely made this a worst case scenario.

[Fiesta]

Almost wasted $300+ My RV has built-in Surge Protection. Check yours first before buying.

[crazyred75]

I think maybe from the metal of the ditch witch trencher and the fresh cut exposed wire arcing maybe cause such and intense surge that in a normal situation of an electrical surge wouldn't cause that much damage. I asked a few electricians at work and they really couldn't explain why the ac adapters would fail. Strange that is for sure. I have wrapped the surge protector and unugged things that don't need to be plugged in during major storms and when I leave for work. Bad enough I have to worry about tornados hittn the trailer but now electrical too! :). Welcome to full time RV'n hey? 🙂 Thank you Pops and everyone for your input!! I def learn a lot from this site!!

[traveylin]

The link to pi ems 50 amp portable is very informative and shows that a very comprehensive list of faults is protected. The OP starting this thread seems to have had one similar yet the failure still occurred. When I used to work we would say the root cause had not been found yet and repeat failure inevitable.

pops

[sljkansas]

PI EMS 50 amp Portable.
Here's the link to what I have and where I bought mine.