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Topic: Over Voltage protection (Read 943 times) previous topic - next topic

Over Voltage protection

Just wondering what to purchase to prevent over voltage, ie; in excess of 130 volt. I am not talking of a surge protector, but something that won't allow more than say, 124 or 128 max voltage to get in the coach. We have been at seveal places where the voltage is just to high, 129-133 volts. The built in protector works in the coack, but would rather have something that would Limit the incoming voltage instead of poping the built in equipment on the coach repeatedly. Also where can something such as this be purchased. Thanx.......JD
Jim Donivan & Cathy Thompson
2003 U320 Designer Series 42' 2 slides

Re: Over Voltage protection

Reply #1 –
I think what you might be looking for is a Progressive Industries product. Their permanently mounted 50 A unit will not allow more than the set upper voltage limit into the coach. If it sees more than that limit it shuts off the electricity inside the coach. I don't have one (need to get one), so I can't tell you exactly what that upper limit point is. There are other devices that can raise or lower voltage somewhat, so maybe that is what you are looking for. I would think that the ideal device would be a combination of the two - the PI unit tells the other machine how much to raise or lower the voltage to get it in specs.

Re: Over Voltage protection

Reply #2 –
Quote from: kb0zke –
I think what you might be looking for is a Progressive Industries product. Their permanently mounted 50 A unit will not allow more than the set upper voltage limit into the coach. If it sees more than that limit it shuts off the electricity inside the coach. I don't have one (need to get one), so I can't tell you exactly what that upper limit point is.

That is what we use - the HW50C model.  IIRC the upper limit is 132 Vac.  It has protected our coach several times from high voltage that occurred during stays at campgrounds (we do have the OEM high/low in our transfer switch, but the Progressive unit responded quicker to a sudden bad situation).

Unit with remote display (what we have, and we have 2 displays with a switch box, one display in the utility bay, one inside the coach near the Power Line Monitor):
http://www.progressiveindustries.net/ems_hw50c.htm

Unit with built-in display (cheaper, but you have to go look at it for info):
EMS-LCHW50C

Portable unit with built-in display (more expensive, but doesn't have to be wired in.  You do have to remember to use it, and it can be challenging to figure out how to secure it from theft if that's a concern for you):
EMS-PT50C
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Over Voltage protection

Reply #3 –
I looked up the item listed,but not what I am looking for. I am hoping to find a limiting device that will somehow keep the flow of electricity on but limit it to acceptable levels when it does get to high.
Jim Donivan & Cathy Thompson
2003 U320 Designer Series 42' 2 slides

Re: Over Voltage protection

Reply #4 –
Quote from: jdent2 –
I am hoping to find a limiting device that will somehow keep the flow of electricity on but limit it to acceptable levels when it does get to high.

Ah, gotcha.  I'm not aware of such a device (doesn't mean there isn't one).  Know of "boosting" ones (Hughes autoformer) but not something that regulates/variably controls on the high end (especially since that could be the result of a poor neutral on the supply side - not something readily handled at the receiving end of things).
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Over Voltage protection

Reply #5 –
Quote from: Michelle –
Ah, gotcha.  I'm not aware of such a device (doesn't mean there isn't one).  Know of "boosting" ones (Hughes autoformer) but not something that regulates/variably controls on the high end.

As I recall, the Hughes Autoformer will either increase or reduce the voltage slightly according to need.
Tom Lang K6PG (originally  KC6UEC)
and Diane Lang
2003 38 U295 build 6209
2016 Jeep Grand Cherokee Summit Ecodiesel
still have tow-ready 2006 Acura MDX 
Temple City, California
Motorcade 16681 California Chapter President
SKP 16663 member of SKP Park of the Sierra, Coarsegold California
FMCA F071251
Retired electrical and electronic engineer

Re: Over Voltage protection

Reply #6 –
Quote from: Tom Lang –
As I recall, the Hughes Autoformer will either increase or reduce the voltage slightly according to need.

They do vary the amount of boost (by limiting current), but they don't do the opposite.

Hughes - Hughes

A concern with higher-than-normal voltage is that there's a good possibility of a safety hazard causing the problem.

ETA some info here RV Electric click on "Open Neutral" on the left menu list
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Over Voltage protection

Reply #7 –
The need to reduce high AC voltage and increase low AC voltage is a common item in the utility business. It is called a Buck / Boost transformer and there are manual ones where we pick the transformer windings, or automatic (autoformer) where a circuit board monitors the incoming voltage and then chooses the correct transformer windings.

Popular RV autoformers are marketed to increase only, so they are Boost transformers. We own a Hughes 50-amp Autoformer, but have never opened case so we don't know what is inside.

Here is a write-up that explains how these transformers work:
Autoformer Usage

Re: Over Voltage protection

Reply #8 –
Thanks to all for the timely reply, I have now alot of food for thought. Thank You all..............JD
Jim Donivan & Cathy Thompson
2003 U320 Designer Series 42' 2 slides

Re: Over Voltage protection

Reply #9 –
Industry standard is plus/minu 10%. 120V nominal plus 10% = 132. Realistically, I wouldn't worry much as long as voltage remains below 140. I'd rather have higher voltage than low volage.
1998 U270 34'

Re: Over Voltage protection

Reply #10 –
Also that readout by the prosine is not accurate and can vary quite a bit too.
2025 Wanderbox Outpost 32 on F600 Expedition Motorhome
2015 Born Free Royal Splendor on Ford 550 nonslide version  for sale
Former Coaches  covering. 360,000 miles
1999 34 U270
2000 36 U320
2001 42' double slide U320
2018 Jeep Rubicon

Re: Over Voltage protection

Reply #11 –
Quote from: Dave M –
When I did the upgrade to the display for the Prosine, was able to calibrate the AC Voltage display using my Fluke 87 series meter, so feel very comfy with the readout.

Did the same on my Progressive surge protector.  The two blue pots with micro screws located on top of circuit board adjust each leg individually.  They had about a 10% error according to Mr. Fluke.
"Not so  long ago we were a nation of risk takers, riding five million pounds of  thrust straight into space."  Joe Gresh
Chuck Pearson
1996 U295
2018 Can Am X3 TurboRS

Re: Over Voltage protection

Reply #12 –
RE: Did the same on my Progressive surge protector. The two blue pots with micro screws located on top of circuit board adjust each leg individually. They had about a 10% error according to Mr. Fluke.

Progressive Industries EMS does not use RMS calculation, like Mr. Fluke.

Re: Over Voltage protection

Reply #13 –
Quote from: Barry & Cindy –
Progressive Industries EMS does not use RMS calculation, like Mr. Fluke.

I do believe US mains voltage is typically stated as RMS, not peak or peak to peak.  If the Progressive surge protector was showing peak for 125V mains power, it would be showing around 170 volts.  As it was, 120 V on the Fluke meter was showing up as 132 V on the Progressive readout, it was tripping on over voltage frequently.  Trimming the pots cured this.  Hopefully I have not rendered the device inoperable by "fixing" it!
"Not so  long ago we were a nation of risk takers, riding five million pounds of  thrust straight into space."  Joe Gresh
Chuck Pearson
1996 U295
2018 Can Am X3 TurboRS

Re: Over Voltage protection

Reply #14 –
Quote from: Barry & Cindy –
Progressive Industries EMS does not use RMS calculation, like Mr. Fluke.

It doesn't matter on pure sin wave AC power.

It DOES matter when measuring chopped power like from an inverter.
1998 U270 34'

Re: Over Voltage protection

Reply #15 –
RE: If the Progressive surge protector was showing peak for 125V mains power, it would be showing around 170 volts

When a consumer meter does not use RMS for their AC metering voltage calculation, they use an averaging method to display voltage, not peak to peak.

Re: Over Voltage protection

Reply #16 –
Quote from: Barry & Cindy –
RE: If the Progressive surge protector was showing peak for 125V mains power, it would be showing around 170 volts

When a consumer meter does not use RMS for their AC metering voltage calculation, they use an averaging method to display voltage, not peak to peak.

But the result is that same number on a relatively true sine wave.
Tom Lang K6PG (originally  KC6UEC)
and Diane Lang
2003 38 U295 build 6209
2016 Jeep Grand Cherokee Summit Ecodiesel
still have tow-ready 2006 Acura MDX 
Temple City, California
Motorcade 16681 California Chapter President
SKP 16663 member of SKP Park of the Sierra, Coarsegold California
FMCA F071251
Retired electrical and electronic engineer
 

Re: Over Voltage protection

Reply #18 –

 I just installed an ECOWISE voltage regulator as my "surge guard" was leaving me without power during most nights and a few days. Not nice running the generator in the campground. The power is very high here, 132.8 etc Mazatlan Mexico. The thing cost almost 7000 pesos to buy and install and of course there are no RV plugs! Had to chop a spare 30 to 50 amp dog bone.
2000  42 U320 DGFE full body paint/modified front lower cap, Build# 5742
2004 C-RV Toad
Tom and Mary, Trouble & Mr. Pants