Low Shore Voltage

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Last week we ran into an issue where the campground shore power for our site was only coming in at 104 volts(30 amps). We have a Progressive surge protector and it would not let the power flow. Reported it as a Low Voltage. The campground was full so we ended going somewhere else at a lot more money but we enjoyed the weekend.

The campground staff was like it ran for the other folks fine. Indicating we would be OK to run without the surge protection. I was always under the impression that low power was just as bad as too much and not wanting to take a risk with the A/C and other components. The Progressive protector being our guide.

So, were we right to leave to avoid this power issue?

[bobndot]

myredracer wrote:
We don't use the autoformer often, but it has been a godsend when needed, esp. when it's been killer hot out.

My DW has asked a few times, 'why do we carry this heavy box' ?
Yes, it's not that often, in fact she keeps forgetting she asked the question previously . :B
When we need it is a 'godsend' . Next time she asks me what this box is , I think I will call it that instead of an autoformer . :C

[myredracer]

solismaris wrote:
I have used my microwave and AC (not together) even when the shore voltage is around the 100V mark. Successfully.

Just because someone can get an AC unit to run "succesfully" on low voltage doesn't mean it's okay to do. Unfortunately, lots of folks do this without knowing the consequences.

Low voltage causes the windings on motors in AC units to overheat and the insulation to degrade. The damage will not be apparent immediately and is cumulative over time. An AC unit can fail prematurely some day for no apparent reason because it was run under low voltage too often. Replacing an AC unit isn't inexpensive and having one fail can ruin a vacation.

Either turn an AC unit off, find a site or CG with better voltage or use an autoformer. While running our AC unit yesterday, our EMS shut us off when I turned the MW on due to low volts. Got the autoformer out and were able to carry on without issues. We don't use the autoformer often, but it has been a godsend when needed, esp. when it's been killer hot out.

[solismaris]

Ok, I'll admit I live dangerously. I have used my microwave and AC (not together) even when the shore voltage is around the 100V mark. Successfully.

I know it is considered harmful to do so. Microwave and AC are the most susceptible to damage by this. Most other things; not so much. Electronics (computers, TVs, etc.) are completely safe to do this, as are lights, toasters, coffeemakers, etc. No problems yet in my 10 year old camper (but I don't do this every day.)

I see low voltage very often in camping. I think the cost for most campgrounds to upgrade to proper wiring is prohibitive for many.

[time2roll]

GordonThree wrote:
Would this work for running just the AC on a 30 amp rig?

Tripp Lite automatic voltage regulator

I have thought about that item for just the A/C circuit. Would have to remove the PI-EMS in the 30 amp feeder.

[GordonThree]

pianotuna wrote:
Hi GordonThree,

I did consider adding one. Here are the specifications:

Voltage Regulation: +10%/-12%
Input voltages over 128V are reduced by 9.6%
Input voltages between 103 and 112V are boosted by 8.9%
Input voltages below 102V are boosted by 18.8%

Maintains usable 120V nominal output during brownouts as low as 87V and overvoltages as high as 140V

I would guess "yes". It would have to be placed after the circuit breaker for the air conditioner. It might be that there is too much start up surge for this unit.

I decided that the 4000 VA Sola Basic was a better fit as it can deal with an entire 30 amp RV (which is me)

Good point, it might not have the grunt to handle the 56 LRA on my rooftop. Going from 2400VA to 3600+ really runs the price up.

I was thinking of switching my AC to a separate cord, so I could either plug it into a dedicated outlet in the RV (wired to the AC's former breaker,) with or without a booster, or into its own extension cord to a 20 amp circuit at the pedestal again with or without booster.

8 out of 10 times I'm camping on my own electric service, using a generator. The 9th time, I'm in a mostly empty park, outside of air conditioning season, so this is for the 1 in 10 chance I'm at a electric park suffering under peak demand.

[pianotuna]

Hi GordonThree,

I did consider adding one. Here are the specifications:

Voltage Regulation: +10%/-12%
Input voltages over 128V are reduced by 9.6%
Input voltages between 103 and 112V are boosted by 8.9%
Input voltages below 102V are boosted by 18.8%

Maintains usable 120V nominal output during brownouts as low as 87V and overvoltages as high as 140V

I would guess "yes". It would have to be placed after the circuit breaker for the air conditioner. It might be that there is too much start up surge for this unit.

I decided that the 4000 VA Sola Basic was a better fit as it can deal with an entire 30 amp RV (which is me)

[GordonThree]

Would this work for running just the AC on a 30 amp rig?

Tripp Lite automatic voltage regulator

[SoundGuy]

bobndot wrote:
During this past heatwave, we were at a KOA with 95v at the peds and most of the Rv'ers that I spoke to had no idea there was low voltage and didn't seem concerned about it. :h It amazes me that so many people spend so much money on these rv's and are clueless to how they work.

Having been involved in this sport for 20 yrs now and having interacted with countless other RV owners over those years I'd say your assessment is sadly right on the money. 😞 Actually, I'd say it's shocking how little so many know about their rigs, the attitude largely being the same as it is with their cars - just put gas in it as necessary and drive it, otherwise they don't want to know anything about anything. :S

As we all know it just doesn't work that way in the world of RVs. :R

[bobndot]

We hardly ever go to CG's because we boondock most all of the time. During this past heatwave, we were at a KOA with 95v at the peds and most of the Rv'ers that I spoke to had no idea there was low voltage and didn't seem concerned about it. :h It amazes me that so many people spend so much money on these rv's and are clueless to how they work.
The owner of the CG said the state of VT. grid system can't handle a heatwave like they had 2 weeks ago.

I ran my Hughes Autoformer in conjunction with my 2 surge protectors and it boosted me to 110-115v to get me thru 2 days.
I was plugged into a 30 amp and it tripped the breaker after the 2nd day so I switched to another 30 amp plug and it got me thru another day using the Hughes.
The following day an opening for a site became avl at a state park with no hookups on a shaded site. That worked for me , I ran my genny with trouble free electricity and used my inexpensive 100w Harbor freight solar panels and all was fine.

[pianotuna]

I do the same for the Magnum inverter charger. That meant when it failed I was back up and running in less than one minute.

[SoundGuy]

pianotuna wrote:
Many of us have "cut the cord". That allows me to place the autoformer close to the RV.

I prefer my devices to be "plug and play" because if the autoformer should fail I would not want to have the issue of having to wire around it.

Which one can also easily do with an EMS, regardless of whether it's a hard wire or portable version. Want to quickly remove it? - just unplug it and butt the two main service cables back together and you're up and running.

[pianotuna]

Many of us have "cut the cord". That allows me to place the autoformer close to the RV.

I prefer my devices to be "plug and play" because if the autoformer should fail I would not want to have the issue of having to wire around it. I added one 30 amp female plug to the Sola Basic, and two 15 amp. One 15 amp allows me to monitor the input voltage--and the other the output voltage.

[SoundGuy]

SoundGuy wrote:
As far as low voltage is concerned, if you've decided against an autoformer as a solution then your other best choice is an EMS with low voltage threshold disconnect. In that case it might be reasonably argued that a hard wire version wired in at the trailer end is a better choice than a portable version because any voltage drop will include that caused by resistance of the main service cable feeding the trailer. With a portable unit plugged in at the post it's only displaying source voltage at that location, before main service cable resistance results in further voltage drop. That's not to say one can't locate a portable at the trailer, even inside where a hard wire would normally be located, but I'd bet very few owners of portable EMS units actually do this and instead simply plug in at the post thinking that's all there is to it. 😉

valhalla360 wrote:
Hard wiring inside the rig adds convenience/security but doesn't make a lot of difference in the voltage that gets to the appliance.
-Boost then it drops over the length of the cord
-Drops over the length of the cord then boost

Especially if you need an extension on your cord because the pedestal is a long way away, having the booster near the pedestal means the cord is running at lower amps which reduces voltage loss in the cord and the likelihood of the cord/plugs overheating.

Read my post again - my comments about location are in reference to an EMS not a voltage booster and yes, with an EMS where it's wired in does make a difference. :R

[valhalla360]

SoundGuy wrote:

As far as low voltage is concerned, if you've decided against an autoformer as a solution then your other best choice is an EMS with low voltage threshold disconnect. In that case it might be reasonably argued that a hard wire version wired in at the trailer end is a better choice than a portable version because any voltage drop will include that caused by resistance of the main service cable feeding the trailer. With a portable unit plugged in at the post it's only displaying source voltage at that location, before main service cable resistance results in further voltage drop. That's not to say one can't locate a portable at the trailer, even inside where a hard wire would normally be located, but I'd bet very few owners of portable EMS units actually do this and instead simply plug in at the post thinking that's all there is to it. 😉

Hard wiring inside the rig adds convenience/security but doesn't make a lot of difference in the voltage that gets to the appliance.
-Boost then it drops over the length of the cord
-Drops over the length of the cord then boost

Especially if you need an extension on your cord because the pedestal is a long way away, having the booster near the pedestal means the cord is running at lower amps which reduces voltage loss in the cord and the likelihood of the cord/plugs overheating.