Go Back   iRV2 Forums > MOTORHOME FORUMS > Class A Motorhome Discussions
Click Here to Login
Join iRV2 Today

Mission Statement: Supporting thoughtful exchange of knowledge, values and experience among RV enthusiasts.
Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on iRV2
 
Thread Tools Search this Thread Display Modes
 
Old 05-25-2013, 10:18 AM   #1
Junior Member
 
Join Date: Apr 2013
Posts: 13
low amperage

i was camping last week at an older camp ground in south louisiana and was having trouble with the breaker at the campground kicking off in the extreme heat of the day. this is the first and only time this has happened since i got the motorhome about 2 months ago. had an electrician check and he told me i was pulling 26 amps on a 30 amp system. i have a 04 pace arrow with the 30 amp shed system. i was running both air conditioners and this only happened around 3pm -6 pm in the evening . the coach units ran all night and all day until this time of evening. i had camped for 4 day in the same weather at a campground approx 15 miles from this campground with no problem. the electrician thought i had a problem with the coach. i got home plugged in to power at the house let both airs run at the same time of day and did not have a problem. i think the problem was low voltage at the campground. any thoughts from more experienced campers. thanks in advance.
__________________

__________________
Jimdel41 is offline   Reply With Quote
Join the #1 RV Forum Today - It's Totally Free!

iRV2.com RV Community - Are you about to start a new improvement on your RV or need some help with some maintenance? Do you need advice on what products to buy? Or maybe you can give others some advice? No matter where you fit in you'll find that iRV2 is a great community to join. Best of all it's totally FREE!

You are currently viewing our boards as a guest so you have limited access to our community. Please take the time to register and you will gain a lot of great new features including; the ability to participate in discussions, network with other RV owners, see fewer ads, upload photographs, create an RV blog, send private messages and so much, much more!

Old 05-25-2013, 11:00 AM   #2
Senior Member
 
jzick's Avatar
 
Join Date: Feb 2007
Location: Florida
Posts: 1,193
Another good reason to always use an energy management system that will monitor electric. Low/fluctuating power can cause serious damage to AC units and other electrical stuff.
__________________

__________________
jzick is offline   Reply With Quote
Old 05-25-2013, 11:11 AM   #3
Senior Member
 
Join Date: Mar 2013
Location: Langley. BC, Canada
Posts: 677
Almost guarantee it was low voltage. If it gets down to 105 volts and less, that's not good. It's bad for some appliances and components and can cause damage. It's especially hard on AC units.

If it drops to 105V, you should "power down" and go on life support. Lights will be okay since running on 12V. Anything that has a resistive element only inside such as a coffee maker or toaster will still function but will take a lot longer to work. Power output (watts) varies as square of the voltage so at 105V a toaster would be putting out 76% of it's normal rating.

It's a good idea to have a power line voltage monitor like the inexpensive ones CW has. I bought a permanent LED monitor that recesses into a wall.

Is there anything you can do? Yes. There is something called a Franks autotransformer that will boost the voltage back up to the normal/nominal level automatically. Not cheap and they're heavy. ww.voltagebooster.com/ If you do decide to get one, understand that nothing is free in life and if you boost your voltage back to 120V, this device only makes it worse for everyone else in the campground. I do not advocate these for that reason and if you hear your fellow RVers cursing and screaming when you have one, you'll have to decide if you'll be able to sleep at night. Actually, if enough people had one in a cg, the entire system could be taken down.

Some campgrounds were just never designed to handle simultaneous heavy loads. Not sure what you can do in advance to find out and I guess the only thing is to read reviews. We were in one cg in Oregon 2 summers ago and the wiring was all strung up between the trees. Some of it was Romex which wouldn't even be legal. Our breaker box was swinging free from the wire attachment point 15' up the tree. No issues with ACs due to all the trees and mostly smaller trailers, but in the morning with lots of cooking appliances running it got down to almost 105 volts.

If you can, you are probably going to be better off the closer you are to the main source of power. If you can spot the incoming overhead high voltage wires and it comes in ear the office, get a site nearest to that.
__________________
Gil & Deb & Dougal the Springer Spaniel
2014 KZ Spree 262RKS & Ford F250 supercab V10 4x4 LB
Langley, B.C.
myredracer is offline   Reply With Quote
Old 05-25-2013, 11:12 AM   #4
Senior Member
 
Join Date: Mar 2010
Location: Cumming, GA.
Posts: 103
You were running close to 30 amps with just the to A/Cs.
As soon as the frig or water pump or battery charger or whatever kicked in you would blow the breaker.

You can't run to A/C plus other stuff at the same time.
__________________
rexabbot is offline   Reply With Quote
Old 05-25-2013, 11:25 AM   #5
Senior Member
 
FlyingDiver's Avatar
 
Newmar Owners Club
Join Date: May 2007
Location: Somewhere....
Posts: 3,820
If the feed voltage was too low, the amperage pulled would have gone up. I agree with myredracer - the campground power was low.

Also, officially the lower limit is 108V. Nominal is 120V, +/- 10%, so 108-132 are the limits. Outside of that, you need to disconnect.
__________________
2008 King Aire 4562, Spartan K3(GT) w/ Cummins ISX 600
2014 Jeep Grand Cherokee Overland 5.7L V8 Hemi w/ Blue Ox Aventa LX Tow Bar and baseplate, SMI Air Force One brake
FlyingDiver is offline   Reply With Quote
Old 05-25-2013, 11:32 AM   #6
Senior Member
 
flaggship1's Avatar


 
Fleetwood Owners Club
iRV2 No Limits Club
Join Date: Sep 2012
Location: Rainbow Riding
Posts: 18,394
Myredracer - I am not familiar with a Franks Autoformer - I know the Hughes Autoformer and I have a PowerMaster Voltage Controller VC50.

I'm curious where you found your facts on a voltage controller or autoformer taking down the power grid for others. I think DWs hair dryer stands a better chance of doing that than the draw from the PM VC. Any info appreciated.

That said - if I read the OP correctly the breaker at the post was tripping. Are you saying a Voltage Controller / Autoformer would have prevented that? I'm ready to learn and appreciate your insight.

Also - glad I have mine mounted in my electric bay with my PI SP.
Steve
__________________
Steve & Annie (RVM2)
2008 Fleetwood Bounder 38F ~ 325 ISB Turbo ~ Freightliner XC 2014 CR-V ~ Invisibrake / Sterling All Terrain
Sioux Falls, SD (FullTime Since Nov 5th 2014)
flaggship1 is offline   Reply With Quote
Old 05-25-2013, 11:56 AM   #7
Senior Member
 
FlyingDiver's Avatar
 
Newmar Owners Club
Join Date: May 2007
Location: Somewhere....
Posts: 3,820
Quote:
Originally Posted by flaggship1 View Post
I'm curious where you found your facts on a voltage controller or autoformer taking down the power grid for others. I think DWs hair dryer stands a better chance of doing that than the draw from the PM VC. Any info appreciated.
This is a common meme in the RVing community. The reasoning is that using an Autoformer to raise the voltage also raises the current draw. So if your demand is 20 amps at 120V (2400 watts), you'll be pulling 24amps if the pedestal voltage is 1000V (still 2400 watts). Plus a little for the inefficiency in the autoformer. A couple percent, maybe. If everyone (or a significant percentage) does that, then the amp draw on the park transformer goes up 10-20%, which drives the voltage down even further, which raises the amperage, etc, etc, until the transformer breakers kick off.

Could it happen? Sure. Is it likely? Depends on how bad the park power really is.

I don't have an autoformer, but I might get one in the future, but only for a specific case. My hookup at my dad's farm is low voltage, but only because it's undersized and a long ways from his main panel. Using an autoformer on that line isn't going to effect his house or anything else.
__________________
2008 King Aire 4562, Spartan K3(GT) w/ Cummins ISX 600
2014 Jeep Grand Cherokee Overland 5.7L V8 Hemi w/ Blue Ox Aventa LX Tow Bar and baseplate, SMI Air Force One brake
FlyingDiver is offline   Reply With Quote
Old 05-25-2013, 11:59 AM   #8
YC1
Senior Member
 
YC1's Avatar


 
Holiday Rambler Owners Club
Join Date: Jun 2011
Posts: 5,570
Was the breaker panel in the direct sun? If so put some shade over it. Not unusual to lose some capacity on a hot breaker panel.
__________________
Myron & Deborah
08 HR Endeavor 40 SKQ
2012 Ford Edge Limited FWD 3.5L
Aluminator tow bar, Demco base plate
YC1 is offline   Reply With Quote
Old 05-25-2013, 12:26 PM   #9
Senior Member
 
Join Date: Mar 2013
Location: Langley. BC, Canada
Posts: 677
flagg,

Being an electrical engineer, that's my area of specialty... To simplify it, power into the autotransf. (watts = volts x amps) = power out. If you up the output voltage from an autotransformer, it's input current will go up when the input voltage falls below the nominal 120V. If you want your full 30 amps delivered at 120 volts and say the pedestal voltage is down to 110 volts, then the input current goes to 120/110 x 30A = 33 amps. It's just basic Ohm's law.

And as FlyingDiver says, if more fellow RVers started to hook up autotransformers, there would be a upwards spiral until the total cg amperage load exceeds the main campground breaker. Probably never happened, but is theoretically possible. This scenario is similar to a utility brownout leading to a blackout. (Utility companies use on-line voltage tap changers to maintain a nominal voltage.)


You'll find lots of discussions and info. in RV forums about the use of autotransformers, like here for example: Positive: Franks Autotransformers - Forest River Forums
__________________
Gil & Deb & Dougal the Springer Spaniel
2014 KZ Spree 262RKS & Ford F250 supercab V10 4x4 LB
Langley, B.C.
myredracer is offline   Reply With Quote
Old 05-25-2013, 01:04 PM   #10
Senior Member
 
flaggship1's Avatar


 
Fleetwood Owners Club
iRV2 No Limits Club
Join Date: Sep 2012
Location: Rainbow Riding
Posts: 18,394
I read much before spending the $650 to buy the PM VC50. I determined it was worth the investment and would do no harm to me or anyone else. I will do some more homework to better understand how the step up process is accomplished such that a 105 input voltage reading at the post - using this
Click image for larger version

Name:	image-1326967948.jpg
Views:	57
Size:	541.5 KB
ID:	39450 pulls more out of the post than 105 being delved to the VC.

I thought I had it right in my mind but apparently it's acting like a vacuum cleaner sucking power from everyone. All I was trying to do was limit ware and tear on my appliances, etc., while getting the 50 amp VAC I was paying for, and no more - while allowing my EMS to shed and keep me going and PI SP to keep me safe from faulty posts.

Back to the text books. Threads can only go so far in educating. Thanks for sharing your expertise.
__________________
Steve & Annie (RVM2)
2008 Fleetwood Bounder 38F ~ 325 ISB Turbo ~ Freightliner XC 2014 CR-V ~ Invisibrake / Sterling All Terrain
Sioux Falls, SD (FullTime Since Nov 5th 2014)
flaggship1 is offline   Reply With Quote
Old 05-25-2013, 01:19 PM   #11
Senior Member
 
FlyingDiver's Avatar
 
Newmar Owners Club
Join Date: May 2007
Location: Somewhere....
Posts: 3,820
Your meter is showing 105V available at the pedestal, right? With the VC-50 in the circuit, what's the voltage? Should be 118V or so (website says max boost 12%). How does it get that extra voltage? By pulling extra current (amps) and converting that to volts. So if you're drawing (for example) 50 amps total (both legs), you're using 50 amps x 118V = 5900 watts. But the input is actually only 105V, so the draw from the pedestal is 5900 / 105 = 56 amps.

56 amps into the VC-50 (at 105V) gives you 50 amps out of the VC-50 (at 118V).
__________________
2008 King Aire 4562, Spartan K3(GT) w/ Cummins ISX 600
2014 Jeep Grand Cherokee Overland 5.7L V8 Hemi w/ Blue Ox Aventa LX Tow Bar and baseplate, SMI Air Force One brake
FlyingDiver is offline   Reply With Quote
Old 05-25-2013, 01:22 PM   #12
Senior Member
 
flaggship1's Avatar


 
Fleetwood Owners Club
iRV2 No Limits Club
Join Date: Sep 2012
Location: Rainbow Riding
Posts: 18,394
Quote:
Originally Posted by FlyingDiver
Your meter is showing 105V available at the pedestal, right? With the VC-50 in the circuit, what's the voltage? Should be 118V or so (website says max boost 12%). How does it get that extra voltage? By pulling extra current (amps) and converting that to volts. So if you're drawing (for example) 50 amps total (both legs), you're using 50 amps x 118V = 5900 watts. But the input is actually only 105V, so the draw from the pedestal is 5900 / 105 = 56 amps.

56 amps into the VC-50 (at 105V) gives you 50 amps out of the VC-50 (at 118V).
Oops - that was hypothetical. On Edit - So the 50 amp breaker at the post let's me pull 56 amps without tripping? I'm going back tongue books. Unfortunately they are in the mh at the shop.
__________________
Steve & Annie (RVM2)
2008 Fleetwood Bounder 38F ~ 325 ISB Turbo ~ Freightliner XC 2014 CR-V ~ Invisibrake / Sterling All Terrain
Sioux Falls, SD (FullTime Since Nov 5th 2014)
flaggship1 is offline   Reply With Quote
Old 05-25-2013, 01:24 PM   #13
Senior Member
 
FlyingDiver's Avatar
 
Newmar Owners Club
Join Date: May 2007
Location: Somewhere....
Posts: 3,820
Quote:
Originally Posted by flaggship1 View Post
Oops - that was hypothetical.
What part? The calculations are the same, just change the draw amp number to what you're actually using. The short answer is, if the VC-50 is doing 12% boost, then you're actually pulling 12% more amps than your inside EMS is showing.
__________________
2008 King Aire 4562, Spartan K3(GT) w/ Cummins ISX 600
2014 Jeep Grand Cherokee Overland 5.7L V8 Hemi w/ Blue Ox Aventa LX Tow Bar and baseplate, SMI Air Force One brake
FlyingDiver is offline   Reply With Quote
Old 05-25-2013, 01:35 PM   #14
Community Moderator
 
"007"'s Avatar


 
Nor'easters Club
Workhorse Chassis Owner
iRV2 No Limits Club
Join Date: Oct 2004
Posts: 26,762
Welcome to irv2.
I would add for starters a Surge Protector if you have none at least it will protect your electronics in your coach from any surges up or down from campground power systems.
__________________

__________________
98KSCA, 99MACA, 03 KSCA-3740- 8.1 Chev-- ALLISON Trans, now in good hands
VISIT the NEWMAR QUICK TIPS & EASYMODS 1 & 2
QUICK TIPS # 3
RV SYSTEMS & APPLIANCES & RECALLS --- TECH INFORMATION
"007" is offline   Reply With Quote
Reply



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Mods to RVs 1stCougar iRV2.com General Discussion 1305 12-11-2017 06:40 PM
Hydraulic Jacks Warning Beeper DuaneInks Class A Motorhome Discussions 10 06-03-2013 10:19 AM

» Virginia Campgrounds

Reviews provided by


Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 01:16 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.