Foretravel Owners' Forum For owners and Fans of Foretravel Motorcoaches September 10, 2025 ...

Two EMS voltage protectors

May 11, 2013, 10:26:35 pm

Several months ago there was a Forum discussion about the pros and cons of wiring Progressive Industries over/under voltage EMS protection before and after the transfer switch.  It seems that each side has advantages and disadvantages. 

Seven years ago, we installed an EMS after our transfer switch and it has worked just fine, and recently protected our coach from a faulty generator voltage regulator. 

During the Forum discussion it was pointed out that a faulty campground connection could take out a transfer switch which could allow faulty current to flow backward and damage our generator.  So we decided to install a second Progressive Industries EMS before our transfer switch and now we are protected on both fronts.

We followed Dave Metzger's lead and used SO #6 cable with 18-10 crimp sleeves to contain the fine strands of copper in relay connectors.
Our kitchen battery monitor corner now has two EMS meters, one we call primary and one called secondary.

Quote Selected

Re: Two EMS voltage protectors

Reply #1 – May 11, 2013, 10:34:31 pm

That's kind of the way I'm leaning, but with several other projects going, and still nine days of school left (and 11 days after that), it will be a while before I actually have to make a decision.

Quote Selected

Re: Two EMS voltage protectors

Reply #2 – May 12, 2013, 03:11:12 pm

I am considering a hardwired ems also. My question is, what if the ems fails? That leaves you with no way to apply power while waiting for a replacement correct? I thought maybe a plug in would be better if that were to happen you could just unplug it.

Mark

Quote Selected

Re: Two EMS voltage protectors

Reply #3 – May 12, 2013, 03:44:38 pm

Mark,

The hard wired Progressive Industries with remote I have in my coach uses the on/off switch in the remote to bypass the ems.

Plus, if you can put one in yourself, you can remove it too.

Quote Selected

Re: Two EMS voltage protectors

Reply #4 – May 12, 2013, 05:07:38 pm

Mark,

On mine you can open the case and bypass the unit if you don't have the remote switch.  From the manual:

Bypass
Enclosed blue jumper wire allows the user to bypass the computer circuit in the EMS in the event of computer failure, thus allowing AC power into the RV. This does not disable the surge protector portion of the EMS; however, all other features are disabled.

Keith

Quote Selected

Re: Two EMS voltage protectors

Reply #5 – May 12, 2013, 11:27:02 pm

Thanks Rudy and Keith for the info.

Mark

Quote Selected