Forum Discussion

icanon's avatar
icanon
Explorer
Oct 06, 2015

Generator and Surge guard

Question for everyone who uses an inverter generator.
Do you use a surge guard when running a generator or is it not neccessary?
Reason why I know many of you use one to protect a/c from low voltage etc. so is it required? I'm talking surge guard that are not permanently installed, I'm asking about the portable ones.

Thanks

46 Replies

  • icanon wrote:
    Reason why I stated portable is that folk with 'hardwired' have no choice or bypass the system.


    Well that doesn't have to be the case ... regardless of brand all one has to do when wiring in a hard wire surge protector is to add a set of 30 amp connectors to the incoming main service line and a couple of matching 30 amp pigtails to the surge protector itself so it can be removed anytime in seconds, just as I've done.

    Progressive Industries EMS-HW30C Surge Protector - Removable Installation



    Secondly, it should be noted that switching the EMS to "bypass" is a bit of a misnomer as that doesn't actually remove it entirely from the system as the surge protection part of the system always remains active. The only way to truly "bypass" the EMS is to remove it from the system, either physically or by externally switching it out of the system - for simplicity I've chosen the former as I will be doing this whenever I may be plugging into either my 1000 watt PSW inverter or Honda EU2000i inverter genset.

    One might wonder why I chose the hard wire EMS-HW30C over your portable EMS-PT30C which I could have also installed inside the trailer by adding 30 amp connectors to the incoming main service cable ..... :h

    First, and most importantly, my hard wire model is field serviceable so should it ever fail I can repair it myself by simply dropping in a new circuit board that Progressive will supply under terms of the lifetime warranty. OTOH your portable version is factory sealed and must be returned to Progressive for repair ... not as much of an issue for anyone in the US where Progressive Industries is located but much more of a hassle for those of us here Canada as it means dealing with customs.

    Secondly, I can adjust the hard wire version's delay time to either 15 secs or 136 secs ... for now I've left it at 15 sec for the convenience but next season when we begin using our Dometic Brisk II A/C which doesn't have built in compressor delay I'll switch the EMS's delay to 136 secs. Your portable unit is fixed at 136 secs.

    Third, now that I have it installed I really like the informative Monitor Display that scrolls through Error, Previous Error, Incoming Source Voltage, Current Draw, and Frequency. Your portable version does as well but because it would normally be sitting at the campsite post I'd find that much less useful and if I instead installed it inside the camper as I did with my previous portable TRC unit I wouldn't be able to see the display anyway.

    FWIW, first time out last weekend with my new EMS we lost power in the campground several times so not only did the EMS disconnect the trailer from the failing incoming source power the display, by showing a previous error code, told me that in the course of losing that power the source also lost ground. :E Gotta say, I'm really impressed with this Progressive Industries EMS-HW30C. :B
  • Bobbo's avatar
    Bobbo
    Explorer III
    You will get 2 answers to this question, and they are both right.

    Answer 1: You don't need to protect from the generator, as they are far less likely to have power problems.

    Answer2: You need to protect from the generator because they can still have power problems.

    Both are right. Generators do have far fewer power problems, but they still can have problems.

    I put my built-in protection just before the power enters the breaker box so I am protected from the generator too.

    hbillsmith wrote:
    I understand Progressive now sells a bonding plug adapter for the 30amp side.

    By golly, you are right. Look what I just found on the Progressive Industries website for $18.80! Of course, you can still make one for less than $3 by going to a big box hardware store.

    http://www.progressiveindustries.net/#!generator-plug/c1mwy
  • I understand Progressive now sells a bonding plug adapter for the 30amp side.
  • Soundguy thanks

    Reason why I stated portable is that folk with 'hardwired' have no choice or bypass the system.

    Thanks again for info good to know.
  • icanon wrote:
    Question for everyone who uses an inverter generator.
    Do you use a surge guard when running a generator or is it not neccessary?
    Reason why I know many of you use one to protect a/c from low voltage etc. so is it required? I'm talking surge guard that are not permanently installed, I'm asking about the portable ones.


    The correct answer is "it depends" ;) - on the particulars of both the generator and the surge protector you're using and has little to do with whether the surge protector is portable or hard wired.

    I have a Honda EU2000i which has a floating neutral output & an early version TRC Surge Guard #34730 without the LCD display panel and found those two would play well together. I've also powered that early version SG with my EU2000i's floating neutral output bonded and although it worked fine with this particular combination some surge protection owner's manuals warn against bonding. That early version SG was replaced by the #34730-001 which does have an LCD screen but since then that version has been supplanted by the new #34830 which includes open ground detection and I suspect it would not be wise to plug it into a generator's floating neutral output nor would bonding be a good idea.

    Just last week I replaced that portable TRC Surge Guard with a hard wire Progressive Industries EMS-HW30C and the owner's manual specifically warns to never the plug the EMS into any inverter of any kind so emailed PI to see if that includes inverter gensets as well. In the meantime, I wired my new EMS into my trailer using standard 30 amp RV connectors so those times I may want to power the trailer either with my 1000 watt PSW inverter or my Honda EU2000i inverter genset I can simply remove the EMS entirely from the system.

    Generator make / model could also be very important ... consider this Progressive Industries Disclaimer which warns to never use any of their EMS units with a Yamaha EF2000iS generator. I emailed PI for clarification and the answer is this particular genset at certain phases in it's operation produces a non-sinusoidal waveform that can destroy the PI EMS units ... do so and your PI lifetime warranty is voided. This in part is the most recent reply I received from Progressive on this subject ...

    "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."

    As often is the case the devil is in the details and I sure wouldn't take WAGs from online discussions like this as gospel when the only correct answer to your question really is "it depends". ;)

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