Generator and Surge guard

Bobbo wrote:

3oaks wrote:
Wouldn't bonding the neutral and the ground wires together trip the GFIs in the travel trailer?

They are bonded in your S&B house and the GFCI outlets are fine with that. The same is true for the RV. Bond them at the generator and the GFCI outlets will be fine with it.

eggzactly. The generator is now the primary service so you have to wire as such

tamijohnson wrote:
We use the PT50C, but have never had to hook it to a generator yet. Does what y'all are saying apply to the portable units as well? We haven't bought a generator yet, but I'd like to stay away from ones that don't "play well" with my PT50, if possible!
Progressive EMS - PT50C

none of them do but as youve seen, the fix is simple

tamijohnson wrote:
We use the PT50C, but have never had to hook it to a generator yet. Does what y'all are saying apply to the portable units as well? We haven't bought a generator yet, but I'd like to stay away from ones that don't "play well" with my PT50, if possible!
Progressive EMS - PT50C

Presumably if you're using an EMS-PT50C then your rig is wired with 50 amp service, in which case you'd probably be looking for something larger in a genset than a 2K unit. Regardless, I'd still be inclined to heed the Progressive Industries Disclaimer about avoiding use of any of their EMS units with the Yamaha EF2000iS genset, my concern being what about all the other models in the Yamaha generator lineup? ... could any of them also destroy an EMS? :@

FWIW, I emailed Progressive about this and the CSR never directly answered my question, saying only that their EMS units were designed for protecting RV electrical systems running on shore power ... which is a veiled way of saying - use a genset instead of shore power and you're on your own. :E

I find it ironic that the EMS, which is supposed to protect the downstream loads from bad power, can be damaged by bad power.

road-runner wrote:
I find it ironic that the EMS, which is supposed to protect the downstream loads from bad power, can be damaged by bad power.

Not to defend Progressive or TRC or anyone else who manufactures these RV specific surge protectors / EMS devices but this is an oversimplification of fact. As clarified in that email reply from Progressive I posted earlier the company makes it clear that their EMS products are designed to protect an RV's electrical system when being fed "with commercial power supplied by campgrounds". The idea that one might also use it when feeding the RV from any other power source such as a generator or inverter is I suspect an idea borne by those of us who own one of these devices, despite the fact that in some cases there can be critical differences between conventional shore power and that delivered by generators and inverters. Progressive knows that despite this some users will plug their EMS into a generator or inverter anyway, which is the reason the company has posted their EMS / Yamaha EF2000iS Disclaimer. When I asked the company to clarify their position on using my own Honda EU2000i along with my new EMS-HW30C the most the CSR would say is that "many of their customers have had success using various models of Honda generators", meaning Progressive makes no official claim regarding use of any of their EMS products with any power source other than a conventional shore power supply.

All this said, I suspect many if not most EMS / surge protector owners don't understand that these devices are not necessarily a one time, lifetime purchase that will never need repair but that under even under normal operating conditions there could well come a time when the unit will have sustained so many surge / spike hits that it will need repair. The reason is simple - they all use MOVs (Metal Oxide Varistors) as the primary device for redirecting excess current to ground in the case of a voltage surge or spike. MOVs by their nature degrade each time that happens ... given sufficient hits and the MOVs will have to be replaced. Progressive knows this, which I suspect is the reason the company chose to offer a lifetime warranty, as it allows them to proactively deal with this reality and keep their customers happy, their reputation as a manufacturer of quality products intact. It's also the reason I chose their hard wire EMS which can be field serviced by myself rather than a portable version that cannot and must be returned to Progressive for repair.

As so often is the case, the devil is in the details. ;)

SoundGuy wrote:
...the company makes it clear that their EMS products are designed to protect an RV's electrical system when being fed "with commercial power supplied by campgrounds".

Applying simple logic to this detail means that the built-in EMS should not be purchased by anyone who will ever power their RV with a portable generator, or at an RV rally where trailer mounted generators are used to provide power. I don't see this information in the sales material. What I see is "Progressive Industries Portable Electrical Management Systems (EMS) provide full RV protection against all adverse power conditions." (Note it says "portable" but this info is in the material for the hardwire models). Plus, the installation instructions have instructions for installing after the transfer box "for protection from both generator and AC power". So between the company's clarification, the advertising, and the installation instructions there are three different versions of generator support.

SoundGuy wrote:
...the company makes it clear that their EMS products are designed to protect an RV's electrical system when being fed "with commercial power supplied by campgrounds"

road-runner wrote:
Applying simple logic to this detail means that the built-in EMS should not be purchased by anyone who will ever power their RV with a portable generator, or at an RV rally where trailer mounted generators are used to provide power. I don't see this information in the sales material. What I see is "Progressive Industries Portable Electrical Management Systems (EMS) provide full RV protection against all adverse power conditions."

Seems to me that "all adverse power conditions" refers to any variable conditions that may be found in a conventional 120 vac shore power source - i.e. what the Progressive CSR referred to in his email as "commercial power supplied by campgrounds" - not power from any other source such as generators or inverters. Indeed, on Page 3 of the EMS-HW30C owner's manual it says - "Never plug the EMS into an inverter".

road-runner wrote:
So between the company's clarification, the advertising, and the installation instructions there are three different versions of generator support.

I don't see this "generator support" you speak of at all, particularly considering this reply I received from the Progressive CSR when I asked about the implications of using my Honda EU2000i which has a floating neutral output to feed my new EMS ...

"Concerning the use of a generator with an inverter, our EMS are designed to be used in the RV environment using a commercial power source. The hazard to our device when using an aftermarket generator, is that some provide a modified sine output, which can cause damage. Others provide a pure sine wave at all times, and others will switch to a modified sine wave under heavy loads. The portion of our units than can be damaged is the surge protect and is not bypassed using the bypass switch. Since there are many brands of generators on the market and numerous models I can not offer specific guidance on which one to select."

"Generator support"? :h

SoundGuy wrote:

"Generator support"? :h

There are a few items in the installation manual for the hardwired 30 and 50 amp EMSs that say generator support to me:

(1) Section titled "Installation after transfer box for protection from both generator and AC power".

(2) 3 pages of instructions to wire it for this.

(3) The statement "..if power is below 104 volts or 132 volts,the EMS will not turn on, and we recommend using your generator power." (After having wired the EMS for generator protection).

If you don't think this indicates generator support, we just disagree.

SoundGuy wrote:
"Generator support"? :h

road-runner wrote:
There are a few items in the installation manual for the hardwired 30 and 50 amp EMSs that say generator support to me:

(1) Section titled "Installation after transfer box for protection from both generator and AC power".

(2) 3 pages of instructions to wire it for this.

(3) The statement "..if power is below 104 volts or 132 volts,the EMS will not turn on, and we recommend using your generator power." (After having wired the EMS for generator protection).

If you don't think this indicates generator support, we just disagree.

What I'm having difficulty with is Progressive wanting to have it both ways, saying on one hand that their EMS units "are designed to be used in the RV environment using a commercial power source" (which if taken literally excludes anything but shore power), go on to say that they'll void warranty on any EMS used with a Yamaha EF2000iS and that the output signal from the variety of generators on the market varies so much in quality that they won't take any position on recommending any that are safe, or not safe, to use in conjunction with their EMS units, that one should never bond the neutral and ground in an RV system (Page 3 of the owner's manual) yet they themselves sell such a bonding plug, and that their EMS units provide "full RV protection against all adverse power conditions" when in fact use with a genset may be suspect at best and because on Page 3 of the owner's manual it says "Never plug the EMS into an inverter". Good grief, talk about double speak! :S In the several emails I've so far sent to Progressive to clarify just what this all means the CSR in each case skated around the issues and never provided a clear answer as to exactly under what situations their EMS units can be safely used and when they can't. What's so difficult about that? ... spell it out, then we'll know, 'til then we're all just guessing. :M

The OP in his original post asked whether a "Surge Guard" can or should be used when powering an RV with a generator and although he may not realize it much of the answer revolves around the topic of bonding - whether it's a good idea or not, whether it's recommended or not. :h This has all been done before here on the forum, most notably in this 41 page discussion started way back in 2008, and anyone who cares to take the time to read and try to fully understand the issues involved will see that even then quite a few who are much more qualified than most of us here couldn't even agree. :S

I can only offer my own practical experience - my early version TRC #34730 Surge Guard (without the LCD display) would accept and pass the floating neutral output from my Honda EU2000i whether it was bonded or not. When I wrote to TRC about this I received a response from a design engineer, not a CSR, who said that although the unit is passing signal it still may flash a caution light indicating an "open ground" - in reality, mine did not - and based on that I decided to remove the bonding plug I had been using. Whether the later version #34730-001 (with the LCD display) or the newest #34830 which now includes "open ground" detection would behave similarly I'm not sure but I suspect they probably would not pass signal without bonding.

Recently I replaced that TRC Surge Guard with a Progressive Industries EMS-HW30C for the improved features it offers, hence my renewed interest in this subject. To date I've heeded the warnings in the EMS owner's manual which state to not bond neutral to ground and to never plug an inverter into the EMS. Progressive to date has been of no help at all in clarifying just what all this means but having now seen the YouTube Video by Mike Sokol (author of the No Shock Zone) which is linked to on the Progressive Industries website it seems that the Progressive EMS will not pass signal from a generator with a floating neutral output unless it is first bonded. So ... I may not have a choice - if I want to power my trailer with my EU2000i and have the signal pass through my new Progressive EMS I'll probably have to bond it whether I want to or not ... either that or I have to remove the EMS entirely from the system and go without when powering the trailer with my genset. Since Progressive warns to "never" plug their EMS into any inverter I installed my hard wire EMS using 30 amp connectors so I can quickly & easily remove it anytime but given a choice I'd rather not have to remove it when using the generator as source power. My answer therefore to the OP's original question as to whether one can or should use a "Surge Guard" when using a generator as source power still stands - it depends. ;)