Journey with Confidence RV GPS App RV Trip Planner RV LIFE Campground Reviews RV Maintenance Take a Speed Test Free 7 Day Trial ×
 

Go Back   Montana Owners Club - Keystone Montana 5th Wheel Forum > GENERAL DISCUSSIONS > General Discussions about our Montanas
Click Here to Login

Reply
 
Thread Tools Search this Thread Display Modes
 
Old 05-10-2022, 10:54 AM   #21
shippilot
Established Member
 
Join Date: May 2022
Location: seabeck
Posts: 10
M.O.C. #30964
First off, thanks for the help. Update, The GFI was working fine for awhile. Then just stopped working. I assumed it was a faulty GFI. Then in the process of changing it out I noticed all the abnormal volt readings. I’m at work now but looks like I’ve got some troubleshooting to do tonight. I will keep you guys up to date on my progress.
 
shippilot is offline   Reply With Quote
Old 05-10-2022, 11:59 AM   #22
BB_TX
Montana Master
 
Join Date: Oct 2006
Location: McKinney
Posts: 7,133
M.O.C. #6433
Quote:
Originally Posted by jsb5717 View Post
Thanks, this can get confusing for us backyard electricians. My understanding has been that 50amp RV outlet wiring is critical so as not to destroy internal wiring and circuits.

The diagram below is how I've understood it...that 2 separate 125v/50A legs come into the RV power center and are kept separate (yes, 250v total). If you lose one of the 2 legs of power then you lose half of of your outlets...depending on which items are connected to which leg. In order to install a 240v washer/dryer, you'd need to run wiring from each side of the power center, wouldn't you?

I'm wondering how the OP would be reading 240+ volts anywhere in the trailer since everything is distributed as 110v.
I believe the newer rigs come with a load center where the 50 amp breaker is in the center with sub breakers on one side for hot 1 and subs on the other side for hot 2. My 2007 model had a panel with the 50 amp at one end and the breakers to the right and alternating on hot legs like a home panel. I could have installed a linked 2 pole breaker and powered a 240 vac appliance.

The only real concern with the 240 vac is loss of neutral. Then, depending on the load on each leg, you will get something other than 120 vac on each hot leg. You might have 40 vac on one leg and 200 on the other. Whatever they are, the two will always total 240 vac.

As for voltages. 110 vac was the original alternating current voltage created. Later that was raised to 115 vac. And still later raised to the 120 vac in use today. Power companies supply 120/240 +/- 5% to our homes.

OK, enough for today’s lesson. Test on Thursday.
__________________
Bill & Patricia
Riley, our Golden
2007 3075RL (recently sold, currently without)
BB_TX is offline   Reply With Quote
Old 05-10-2022, 12:56 PM   #23
Daryles
Montana Master
 
Daryles's Avatar
 
Join Date: May 2019
Location: Alton
Posts: 2,654
M.O.C. #24086
Jsb5717, you understand it just fine
__________________
Daryl and Marianne,
2019 3130re 20th Anniversary Edition
2016 F350 Lariat
Daryles is offline   Reply With Quote
Old 05-10-2022, 01:03 PM   #24
jsb5717
Montana Master
 
jsb5717's Avatar
 
Join Date: Mar 2019
Location: Milwaukie, OR
Posts: 1,455
M.O.C. #23668
Quote:
Originally Posted by BB_TX View Post
I believe the newer rigs come with a load center where the 50 amp breaker is in the center with sub breakers on one side for hot 1 and subs on the other side for hot 2. My 2007 model had a panel with the 50 amp at one end and the breakers to the right and alternating on hot legs like a home panel. I could have installed a linked 2 pole breaker and powered a 240 vac appliance.

The only real concern with the 240 vac is loss of neutral. Then, depending on the load on each leg, you will get something other than 120 vac on each hot leg. You might have 40 vac on one leg and 200 on the other. Whatever they are, the two will always total 240 vac.

As for voltages. 110 vac was the original alternating current voltage created. Later that was raised to 115 vac. And still later raised to the 120 vac in use today. Power companies supply 120/240 +/- 5% to our homes.

OK, enough for today’s lesson. Test on Thursday.
Man, I hate tests. But I guess if it's part of my final grade...

It makes sense. Sorry, I tend to use 110, 115, 120, and 125v interchangeably. So, it sounds like...regardless of whether the incoming current is managed at the post via the cable or at the power center, the current is always distributed throughout the coach as 120v. And it's possible, with the right breaker setup, to capture 240v if needed.

So, takeaways for the OP:

1. nowhere in the coach, especially through any of the standard wall outlets including GFI, should you have 240+ volts. If so then power is being jumped somewhere it shouldn't be and is a fire hazard.
2. none of the outlets should read voltage on both sides of any of the outlets. If so then there is a short somewhere and is a shock hazard.

Does this make sense?

If it were me I would double check the outlet coming from the house to make sure that each side is sending only 120v. Then I would check the RV power cable for continuity to see of it has an internal short. If both of those check out then I would know the problem is in the trailer. Process of elimination troubleshooting. YMMV
__________________
Jeff & Sandi (and Teddy - 7lb Schnorkie)
2018 Montana HC 305RL / HW Progressive EMS
2015 RAM 3500 Laramie Longhorn Crew Cab 4x4 DRW / Demco Recon Hitch on RAM Puck Ball
jsb5717 is offline   Reply With Quote
Old 05-10-2022, 01:23 PM   #25
jsb5717
Montana Master
 
jsb5717's Avatar
 
Join Date: Mar 2019
Location: Milwaukie, OR
Posts: 1,455
M.O.C. #23668
Quote:
Originally Posted by Daryles View Post
Jsb5717, you understand it just fine
Thanks, I thought I had a decent, basic understanding of how it worked. I'm a pretty handy guy and do all of my own maintenance and repair. Jack of all trades...master of none.

I'm always a little more cautious about electricity since I'm not a pro. I just like to make sure I have decent understanding before working on something. 120v seems pretty basic to me. But 240v makes me pause a little.
__________________
Jeff & Sandi (and Teddy - 7lb Schnorkie)
2018 Montana HC 305RL / HW Progressive EMS
2015 RAM 3500 Laramie Longhorn Crew Cab 4x4 DRW / Demco Recon Hitch on RAM Puck Ball
jsb5717 is offline   Reply With Quote
Old 05-10-2022, 02:20 PM   #26
RipNC
Montana Fan
 
Join Date: Aug 2020
Location: Aurora
Posts: 429
M.O.C. #26926
Jeff,

As Bill said - if you are hooked up to standard CG 50A shorepower and put your leads on L1 and L2 inside your rig you will read +/- 240v. Granted, after the main breaker there are typically no 240v brakers on the panel legs (only single pole 120v breakers), but 240v is there at the main (double pole 50A) breaker.

However, most OEM 5th wheel generators (aka Onan) only output 2 - 120v circuits which are on the same sine wave and each feeds L1/L2 at our transfer switch. On our rig (Onan running) with leads on L1 and L2 will read 120v on a multimeter vs the 240v I get on shorepower.
__________________
Rip & Beth
2021 3121RL Legacy Cobalt FBP, MORryde IS & pin box
2020 F350 PSD CCLB SRW
RipNC is offline   Reply With Quote
Old 05-10-2022, 02:27 PM   #27
RipNC
Montana Fan
 
Join Date: Aug 2020
Location: Aurora
Posts: 429
M.O.C. #26926
Shippilot,

I second Daryles recommendation to test the pedestal (or home 50A receptacle) per the drawing provided and post the readings for feedback.
__________________
Rip & Beth
2021 3121RL Legacy Cobalt FBP, MORryde IS & pin box
2020 F350 PSD CCLB SRW
RipNC is offline   Reply With Quote
Old 05-10-2022, 02:46 PM   #28
RipNC
Montana Fan
 
Join Date: Aug 2020
Location: Aurora
Posts: 429
M.O.C. #26926
Shippilot,

To be clear, +/- 240v (or 250v) reading at the 50A shotepower receptacle is expected but ONLY between L1 and L2 if your reading 250v between other poles (see Daryles attachment) you have a serious problem. Post your test readings here for feedback.
__________________
Rip & Beth
2021 3121RL Legacy Cobalt FBP, MORryde IS & pin box
2020 F350 PSD CCLB SRW
RipNC is offline   Reply With Quote
Old 05-10-2022, 05:35 PM   #29
shippilot
Established Member
 
Join Date: May 2022
Location: seabeck
Posts: 10
M.O.C. #30964
I tested the power coming from the house before the cable as per the test drawing, all good. Then tested the power at the end of the cable, same readings, that told me the cable is good and the power from the house is good.
I’ve opened the power distribution panel and opened the wall behind the breaker box(distribution panel) checked and tightened all neutral and ground connections. Inspected everything I could see and there is no sign of loose or damaged wires.
I was told by a locale tech that sometimes the automatic transfer switch can have a neutral short or something like that. I haven’t checked the switch yet. Not sure how to do that.
Thoughts??
shippilot is offline   Reply With Quote
Old 05-10-2022, 06:05 PM   #30
Daryles
Montana Master
 
Daryles's Avatar
 
Join Date: May 2019
Location: Alton
Posts: 2,654
M.O.C. #24086
I wasn't sure if you had a transfer switch, but yes, that could be a point of failure.
It will be labeled like the picture.
You will test each input side AND the output side (load or RV circuit breaker panel)
Shore, Generator and load

L1-HOT to ground =
L2-HOT to ground =
L1 to neutral =
L2 to neutral =
Neutral to ground =

BE VERY CAREFULL !!!!
TAKE YOUR TIME
Attached Thumbnails
Click image for larger version

Name:	Transfer switch torque.jpg
Views:	22
Size:	140.5 KB
ID:	11922  
Daryles is offline   Reply With Quote
Old 05-10-2022, 07:07 PM   #31
RipNC
Montana Fan
 
Join Date: Aug 2020
Location: Aurora
Posts: 429
M.O.C. #26926
Warning, disconnect all shorepower and inverter before you open the transfer switch incase something is shorted inside. Inspect all interior connections and make sure all are tight and correct before reenergizing and testing.
__________________
Rip & Beth
2021 3121RL Legacy Cobalt FBP, MORryde IS & pin box
2020 F350 PSD CCLB SRW
RipNC is offline   Reply With Quote
Old 05-17-2022, 07:04 AM   #32
shippilot
Established Member
 
Join Date: May 2022
Location: seabeck
Posts: 10
M.O.C. #30964
Update on this power issue. Turns out my volt meter was not showing a dec. point. So the 354 volts was really .354 of a volt. After checking everything else. I tried a new volt meter.. Anyway, the only problem was a bad GFI. Replaced and all works fine. Thank you for all the advice.

Here’s a new issue. The 383th is a toy hauler. If you are familiar with the unit, you know the bed rises in the master bedroom using four electric motors. We got the 2021 RV used and the previous owner had replaced the Rv bed with a very nice but heavy queen sized household one. The lift was not operating properly, so after looking for any pinch points and finding none. I decided to remove the mattress and low and behold the lift works just fine. So my question now is what is the best but lightest Rv bed queen size 60x80. I’m still trying to figure out how heavy I can go and still use the lift. Got to have my toy along.
shippilot is offline   Reply With Quote
Old 05-17-2022, 07:21 AM   #33
mhs4771
Montana Master
 
mhs4771's Avatar
 
Join Date: Dec 2009
Location: Sebring
Posts: 3,657
M.O.C. #9969
Might try a Sleep Number or any of the Air beds, probably can't much lighter.
__________________
Michelle & Ann
2018 Chevy 3500HD High Country DRW 4X4 Crew Cab w/Duramax/Allison, Formally 2010 Montana 2955RL, Now Loaded 2016 SOB, Mor/ryde IS, Disc Brakes & Pin Box, Comfort Ride Hitch, Sailun 17.5 Tires.
mhs4771 is offline   Reply With Quote
Reply

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
Forum Jump

» Featured Campgrounds

Reviews provided by

Powered by vBadvanced CMPS v3.2.3
Disclaimer:

This website is not affiliated with or endorsed by Montana RV, Keystone RV Company or any of its affiliates. This is an independent, unofficial site.


All times are GMT -6. The time now is 09:55 AM.


Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2024, vBulletin Solutions, Inc.