Surge guard

[Freeny]

My surge guard 34750 just quit is there an advantage to having a voltage regulator or is the 50amp surge guard enough protection

[tvman44]

I would get a Progressive Industries EMS-50HWC, far superior unit than the surge guard by TRC.

[SUMDALUS]

Freeny,

A voltage regulator (a.k.a. Autoformer) only has one function - to boost low voltage. The boost may possibly be between 10 to 12 %. If you regularly stay at campgrounds/parks with consistantly low voltage, a autoformer may work well for you. However, this unit does not have the other protections that your original Surge Guard had (e.g. the autoformer only has enough surge protection to protect itself and not your whole RV).

I agree with TVman44's comment about Progressive Industries' Electrical Mangement System (EMS) being far superior {but I'm biased}. If you need an autoformer, the EMS (or Surge Guard) will babysit the autoformer - hook up the automormer first, then the EMS between the autoformer and the RV.

See DriVer's blog www.irv2.com/forums/blogs/driver/mobile-rv-medics-dale-sumner-327/ to see why he has an EMS in his RV.

[RJay]

Hi Dale,
The Progressive Industries(PI) EMS is designed to protect the whole RV. I don't know the joule rating for the autoformer but the PI EMS is rated at 3450 joules of energy. If the joule rating of the autoformer is less then the PI EMS, as you seem to indicate, the PI EMS should be the first unit from the power pedestal followed by the autoformer and finally the automatic transfer switch. This will ensure maximum surge protection to the autoformer and also provide circuit configuration analysis, which I understand is also a feature of the autoformer. I think this is what you meant to say.

[SUMDALUS]

RJay,

Sorry to disagree, but the EMS (or Surge Guard) should be after the autoformer.

Here's why -- The autoformer is attempting to boost low voltage to a level that is safely usable. The EMS protects because it is designed to open the circuit when the voltage reaches a minimum of 104 volts AC.

If the EMS is installed first, the autoformer might not be able to do its job because the EMS shut the power OFF before it could. (The autoformer is capable of boosting voltages up from lower than 104 volts.)

So, by installing the EMS first, you are diminishing the boost capability of the autoformer.

The autoformer can protect itself, the EMS will protect the whole RV.

Hope that makes sense.

[stuhly]

I had a 50 amp surge guard fail in less than 2 years. Called Surge guard to inquire about sending it in for repair. Brain surgeon I got on the phone informed me it was out of warranty and they do not repair them anymore. Told me it was not the unit anyway but bad service at the Park. Same problem at next park. Would work on 30 amp but not 50. He told me that was impossible because the unit couldn't tell the difference between 30 or 50. You don't want to read my reply to that idiot statement. Replaced the unit and all is well. I was in a hurry and surge guard was available so I bought it, however if I was doing it again I wold get something else

[RJay]

Quote:

Originally Posted by SUMDALUS RJay, Sorry to disagree, but the EMS (or Surge Guard) should be after the autoformer. Here's why -- The autoformer is attempting to boost low voltage to a level that is safely usable. The EMS protects because it is designed to open the circuit when the voltage reaches a minimum of 104 volts AC. If the EMS is installed first, the autoformer might not be able to do its job because the EMS shut the power OFF before it could. (The autoformer is capable of boosting voltages up from lower than 104 volts.) So, by installing the EMS first, you are diminishing the boost capability of the autoformer. The autoformer can protect itself, the EMS will protect the whole RV. Hope that makes sense.

Dale,
The Hughes Autoformer turns on the 10% boost when the park voltage is below 116 VAC and turns it off when the park voltage reaches 118 VAC. This is well above the 104 VAC cutoff threshold of the PI EMS. If the autoformer allows voltage to reach 104 VAC I don't see its value. I think the PI EMS is the best on the market but its low voltage cutoff threshold is dismal because motor load damage and lose of life occurs at voltages below 108 VAC and some time could pass from when the voltage reaches 108 VAC to the point of cutoff.

[SUMDALUS]

Rjay,

According to the National Electric Code (NFPA 70) the recommended safe voltage level is between 102 and 132 VAC. Surge Guard meets this spec exactly, while Progress Industries operates between 104 and 132 VAC.

If the incoming power was as low as 95 VAC, a 10% autoformer boost would bring it up to 104 VAC. That means that the incoming power could be 9 volts lower than the EMS minimum and still be boosted above the NEC lower limit of 102. Most autoformers will try to boost voltages as low as 90 VAC - below that they quit.

Please realize, I don't make either product and won't argue against the NEC standards. My answers are based on my own 50+ years experience living in and working on RVs.

Thanks.