Reply
 
Thread Tools Display Modes
Old 06-25-2012, 08:09 PM   #1
Senior Member
 
Sg6923's Avatar
 
Join Date: Mar 2012
Posts: 113
Electrical Problem

I took my 3625RT 5er out last weekend to the same campground we've gone to for years. I hooked the 50 amp cord up and went in to run the slides out. I noticed smoke rolling out if the microwave. I ran out and shut it off, unplugged the microwave and plugged the camper in again. I went in and checked the voltage meter I keep plugged in the 120V outlet. It was all the way over and pegged out on the right and getting very warm. The fuse box switches were in the ON position. The repair center gave a quick look with a 30 amp plug and said my fridge, microwave and AC wouldn't work. All the 12 volt systems seem to work.

Does anyone know what the heck happened? The host.checked the box at the campground and said voltage was okay.

I unplugged and came home.

Thanks,

T-man & Sugar
__________________

__________________
Sg6923 is offline   Reply With Quote
Old 06-25-2012, 08:55 PM   #2
Site Team - Lou
 
Herk7769's Avatar
 
Join Date: Oct 2009
Location: South Eastern PA
Posts: 21,169
This is a classic "Open Neutral"
This results in 240 volts in the camper.

Most likely since the campground checked out ok, the problem is either in your power center or the back of the 50 amp cord socket (or gang box).
__________________

__________________

Lou and Laura with Bella - German Short Hair Pointer
2008 GMC Sierra 2500HD Crewcab SB Allison Duramax
2010 Flagstaff 8526RLWS - Superglide 3300
HAM CALLSIGN - KC3FFW
Herk7769 is offline   Reply With Quote
Old 06-25-2012, 09:42 PM   #3
Member
 
MIKE44460's Avatar
 
Join Date: Apr 2011
Posts: 97
If I was the camp ground I too would of said, I'm good here, must be your equipment. You may be looking at a big expense. I would of had someone check their power before you pulled out. I carry an amp probe and meter and will check voltage before I plug in.
__________________
Mike & Lu Anne
& our Jack Russell 'Genny'
2011 Flagstaff 831FKBSS
2011 Chevy CC Duramax Z/71
OH plate GM DMAX
Hensley Arrow
MIKE44460 is offline   Reply With Quote
Old 06-25-2012, 09:45 PM   #4
Member
 
MIKE44460's Avatar
 
Join Date: Apr 2011
Posts: 97
Herc, what does a neutral have to do with 240AC?
__________________
Mike & Lu Anne
& our Jack Russell 'Genny'
2011 Flagstaff 831FKBSS
2011 Chevy CC Duramax Z/71
OH plate GM DMAX
Hensley Arrow
MIKE44460 is offline   Reply With Quote
Old 06-25-2012, 09:49 PM   #5
DDC
Senior Member
 
DDC's Avatar
 
Join Date: Sep 2011
Location: Komoka Ontario
Posts: 2,364
I would imagine this is why some of us use a Surge Protector with Voltage Protection although if the fault is in the tailer it would not help either.
__________________
"Well that didn't go as expected"
2015 Chev 2500HD Highcountry Duramax
Cedar Creek Silverback 33IK
Donald&Casey cairn terrier
Rest in Peace Mary my darling wife.
Scottish by birth Canadian by time.
DDC is offline   Reply With Quote
Old 06-25-2012, 11:09 PM   #6
Senior Member
 
Sg6923's Avatar
 
Join Date: Mar 2012
Posts: 113
Thanks for the info. Pretty sure he's on the up and up. I watched him check it and others around that we're hooked up. It had the same readings as the others. Thanks.
__________________
Sg6923 is offline   Reply With Quote
Old 06-25-2012, 11:38 PM   #7
Senior Member
 
Join Date: May 2012
Posts: 513
Quote:
Originally Posted by MIKE44460 View Post
Herc, what does a neutral have to do with 240AC?
A 50A connection should be similar to the power coming into your house. You probably have three wires: a neutral, and two hot wires. You get 120V between each hot wire and the neutral. If you measure between the hot wires, you'll discover that you have 240V. This is caused by the two 120 hot lines being out of phase with each other. A ground is generated by connecting the metal fuse/circuit breaker box to a water pipe which is buried in the ground. (Interesting question - what about new houses using plastic pipe? They'll require a grounding rod system to meet electrical code standards.) Since your motor home doesn't have a buried metal water pipe to provide a ground, the campground needs to provide one for you. This creates the four pronged 50A outlet.

If the neutral line is disconnected at the campground connection and you have an active electrical device connected to each of the hot lines, then 240V will appear across the two devices. If both were 100W bulbs, you could get away with this but when the devices have different wattage ratings, the current flowing in the device with the higher wattage rating will be greater (and can be much much greater) than the designed rating of the device. This was the cause of the smoke you saw.

When you connect your campground hookup, two devices are usually immediately powered up; the refrigerator and the converter. It's very likely that they are on different hot lines of the 50A circuit and could cause this problem. If you have a TV with "instant on", it also starts drawing power as soon as the AC appears at the plug.

Understanding how AC power works and knowing how to use a meter that lets you check each "circuit" in a 50A outlet will prevent this problem. When I check an outlet at a campground, I check each hot line to neutral for 120V, check across the hot lines for 240V, then check for voltage between neutral and ground. If no voltage between neutral and ground, I check the resistance between neutral and ground to verify that they're bonded together somewhere before the outlet. The neutral line is normally grounded at the power company's transformer that converts the (usually) 3Kv supply line to the lower voltage supplied to the campground. A large campground is more like a housing subdivision and may have multiple transformers and ground points. Bad connections at power poles can have interesting effects on outlets in one area of a park but not in others.

Phil
__________________
pmsherman is offline   Reply With Quote
Old 06-26-2012, 12:18 PM   #8
Member
 
MIKE44460's Avatar
 
Join Date: Apr 2011
Posts: 97
Phil, if you don't have a nuclear reactor in your basement, you should. Thanks for a very informative reply. Something I will do, for sure, from now on.
__________________
Mike & Lu Anne
& our Jack Russell 'Genny'
2011 Flagstaff 831FKBSS
2011 Chevy CC Duramax Z/71
OH plate GM DMAX
Hensley Arrow
MIKE44460 is offline   Reply With Quote
Old 06-26-2012, 01:14 PM   #9
Site Team - Lou
 
Herk7769's Avatar
 
Join Date: Oct 2009
Location: South Eastern PA
Posts: 21,169
Phil's reply was perfect. Thanks were sent (and sent again here).

If the neutral fault is in your camper (at the main circuits), it is possible to have an issue at the power center in your camper that would not show up at the pole. 240 VAC could still appear across some circuits depending on how the power center was wired, if the white neutral came loose at the common buss. The connection between the two "hots" would then be through the ungrounded "neutral" buss.

The damage will be the same; just the campground would have an "out."
__________________

Lou and Laura with Bella - German Short Hair Pointer
2008 GMC Sierra 2500HD Crewcab SB Allison Duramax
2010 Flagstaff 8526RLWS - Superglide 3300
HAM CALLSIGN - KC3FFW
Herk7769 is offline   Reply With Quote
Old 06-26-2012, 05:30 PM   #10
Senior Member
 
Join Date: May 2012
Posts: 513
Quote:
Originally Posted by MIKE44460 View Post
Phil, if you don't have a nuclear reactor in your basement, you should. Thanks for a very informative reply. Something I will do, for sure, from now on.
It doesn't require a nuclear reactor. What got me started was the standard college preparation high school program I went through:
4 years math
4 years english
4 years history, social studies, government
4 years sciences
4 years gym
2 years foreign language
2 years mechanical drawing
1 years freehand drawing
2 years machine shop
1 semester each - woodworking, foundry, commercial printing, tinsmithing

Round that off with a stint in the military, a couple of college degrees, a 45 year marriage, two independent adult children, a 50 year interest in amateur radio (including climbing a 100' tower and helping install a repeater antenna on another that was hot with 50kw of RF energy), a lifelong interest in photography and astronomy, 35 years as a DIY homeowner (painting, woodworking, carpeting, plumbing, wallpapering, electrical work, masonry, and tree removal), 25 years as a member of the National Ski Patrol, and over 20 years of IBM selling my IT skills by the hour and I figure that by now I have the beginnings of a fairly well rounded skill set.

Phil
__________________

__________________
pmsherman is offline   Reply With Quote
Reply

Tags
led pad

Thread Tools
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



» Virginia Campgrounds

Reviews provided by




ForestRiverForums.com is not in any way associated with Forest River, Inc. or its associated RV manufacturing divisions.


Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -5. The time now is 02:38 AM.