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Topic: Voltage Problem (Read 1261 times) previous topic - next topic

Re: Voltage Problem

Reply #25 –
30 amps. one ac, battery charger, fridge, no problem. If you want to run coffee pot, or microwave or any other big draw unit, would turn ac off while it is running.
50 Amp To 30 Amp Adapter | etrailer.com
Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.

Re: Voltage Problem

Reply #26 –
You're missing my question. I know there are adaptors. Bob, the 30 amp you show doesn't have the correct prongs. What I am asking is, IF I had to "rig" the 50 amp line, cut off the plug, and see 4 wires, red, black white and green, and then take my 30 amp pigtail and cut off the female end, which wire would not be used? This is not an ideal fix. It would be undertaken in desperation.
Glenn and Amy Beinfest
2001 36' U320
#5812
2014 Honda CRV

No Whining on the YACHT

Re: Voltage Problem

Reply #27 –
Quote from: GleamB –
You're missing my question. I know there are adaptors. Bob, the 30 amp you show doesn't have the correct prongs. What I am asking is, IF I had to "rig" the 50 amp line, cut off the plug, and see 4 wires, red, black white and green, and then take my 30 amp pigtail and cut off the female end, which wire would not be used? This is not an ideal fix. It would be undertaken in desperation.
Either the red or black, doesn't make a difference.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Voltage Problem

Reply #28 –
Quote from: GleamB –
You're missing my question. I know there are adaptors. Bob, the 30 amp you show doesn't have the correct prongs. What I am asking is, IF I had to "rig" the 50 amp line, cut off the plug, and see 4 wires, red, black white and green, and then take my 30 amp pigtail and cut off the female end, which wire would not be used? This is not an ideal fix. It would be undertaken in desperation.
You need to give us a situation where you could not use the adapter. If you just had to wire a 30 amp plug to 50 amp cable, you could take either black and white or red and white, and of course green for ground. This would give you the same 120 volts that a 30 amp would normally supply.
Using a 50 to 30 Amp RV Power Adapter - RV Basics .com
You will have to scroll down to see it.
Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.

Re: Voltage Problem

Reply #29 –
Quote from: GleamB –
You're missing my question. I know there are adaptors. Bob, the 30 amp you show doesn't have the correct prongs. What I am asking is, IF I had to "rig" the 50 amp line, cut off the plug, and see 4 wires, red, black white and green, and then take my 30 amp pigtail and cut off the female end, which wire would not be used? This is not an ideal fix. It would be undertaken in desperation.
Glenn
If you "cap off" either the black or red wire you will only have power to certain appliances and receptacles in your coach. Capping off may not allow the appliances u need to be working to work. Everything in divided up on each hot wire {red/black} based on the load of each appliance depending on the amp draw of each one and split between the black and red wires. The 30 amp to 50 amp pigtails combine the red/black wires together on the single hot wire on the 30 amp so everything will work in the coach. You, as the owner must make the choice of what will be turned on without overloading the wire and breakers. Just as a side note, breakers are only rated for 80% of the stated load for continuous load. 
I hope this helps
Ron
Ron Clark
Sherwood,Arkansas
1999 U 295 40 foot Build # 5550
2020 Jeep Gladiator
Motorcade # 18173
FMCA # F485593

Re: Voltage Problem

Reply #30 –
We have been in several RV parks with only 30 amp service.  We were able to run 1 air, coffee pot, microwave and most any of our lights, which are LED.  We also had the electric side of the water heater on, however, it did trip the 30 amp pedestal breaker, so shut the electric side down and ran the Aqua Hot instead.  No other issues and we were there for 21 days.
Joe & Dottie Allen
Sold!  December 2023.      2000 U320; build # 5645
Our coach " Maxine"
Motorcade #  15922;  Escapee 150950; FMCA F330833; Boondockers Welcome;  Harvest Hosts;  Thousand Trails
'98 U320 from 2000-'06
USAF '62-'66

"Do not spoil what you have by desiring what you have not; remember that what you now have was once among the things you only hoped for." ―Epicurus

Re: Voltage Problem

Reply #31 –
In "desperation" and having to wire a 30 amp plug with just 3 connectors to your 4 wire 50 amp power cord you could wire the grounds together, the whites together, and wire both of the hots black and red together to the black hot on the 30 amp plug.  Probably would be easiest to get a junction box to do the wiring inside of.  This would give you power to everything in your coach but still be limited to 30 amps.  This is basically what a 50 to 30 amp adapter does.
At least I think this would work, any other thoughts?
Forest & Cindy Olivier
1987 log cabin
2011 Roadtrek C210P
no longer 1999 36' U320 build #5522
2013 Rzr 570 & 2018 Ranger XP1000
2006 Lexus GX470
2011 Tahoe LT 4x4
Previous 1998 45' 2 slide Newell, 1993 39' Newell

Re: Voltage Problem

Reply #32 –
Quote from: GleamB –
You're missing my question. I know there are adaptors. Bob, the 30 amp you show doesn't have the correct prongs. What I am asking is, IF I had to "rig" the 50 amp line, cut off the plug, and see 4 wires, red, black white and green, and then take my 30 amp pigtail and cut off the female end, which wire would not be used? This is not an ideal fix. It would be undertaken in desperation.
To convert your 50 amp cord to a 30 amp RV plug, do this.

Connect both of the cord's hot leads to 30A hot.  The 50A common lead to to the 30A common and the green earth ground to the round pin.  That's all a 50 to 30 dogbone adapter does anyway.
1992 Foretravel Grand Villa
U225 SBID Build No. 4134
1986 Rockwood Driftwood
1968 S.I.A.T.A. Spring
1962 Studebaker Lark
1986 Honda VF700C
1983 Honda VF750C
Charlie, the Dog was broken out of jail 24 Oct 2023
N1RPN
AA1OH (H)e who must be obeyed.

Re: Voltage Problem

Reply #33 –
Other than just looking at AMP consumption the other variable, particularly in some of the older RV parks in Mexico with only 15/20 service is WHAT IS VOLTAGE WHEN HEAVIER LOADS ARE RUNNING.

Said another way an a "good" 20 amp service, you can run one A/C as long as other loads are off.  But when you turn it on, observe voltage carefully.  If it drops to 108 VDC turn it off.  This can happen, even if voltage with no load is 120 VAC due to use of small gauge wire, poor connections, etc.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Voltage Problem

Reply #34 –
Quote from: GleamB –
You're missing my question. I know there are adaptors. Bob, the 30 amp you show doesn't have the correct prongs. What I am asking is, IF I had to "rig" the 50 amp line, cut off the plug, and see 4 wires, red, black white and green, and then take my 30 amp pigtail and cut off the female end, which wire would not be used? This is not an ideal fix. It would be undertaken in desperation.

"It depends"

What do you want to be able to run? 

What phase of the 50 amp is it on?

OK, now, which wire, black or red, feeds the phase you want to run?  (this is a bit more challenging to determine, as you might guess)

If you have something on one phase and something on the other phase you both want to be able to run, cutting one of the hot wires is not an option.  You can only run things on the phase that is still wired.

50 amp wiring in the coach is TWO mains of 50 amp, 120 VAC each, ideally out of phase with each other.  Normal 30 amp RV wiring is ONE main of 30 amp 120 VAC.

RV Electric

50 to 30 (and 50 to 20) adapters tie the 2 50 amp hots together.  Using them, you are now sharing 30 (or 20) amps across both phases, instead of having 50 amps available on each phase, but at least it is a simple, temporary change and not a power cord modification.  And it allows you to run things on either phase as long as you don't pull more current (amps) than the service breaker and adapter is rated for.
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: Voltage Problem

Reply #35 –
Quote from: GleamB –
What I am asking is, IF I had to "rig" the 50 amp line, cut off the plug, and see 4 wires, red, black white and green, and then take my 30 amp pigtail and cut off the female end, which wire would not be used? This is not an ideal fix. It would be undertaken in desperation.

OK to answer your specific question:

30 amp end                Function                    50 amp end

Green                          Ground                        Green
White                          Neutral                        White
Black                          Hot                              BOTH Black and Red
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Voltage Problem

Reply #36 –
Putting the two "hot" lines together is the answer I was after. Thanks to all. I hope I never gave to modify anything other than using a pigtail.
Learned a lot, and hope it was helpful to others.
Glenn and Amy Beinfest
2001 36' U320
#5812
2014 Honda CRV

No Whining on the YACHT

Re: Voltage Problem

Reply #37 –
Brett
It is possible that at some point the neutral and ground  conductors could have been swapped on his cord plug and the "round" prong was his neutral. ?
I agree that the broken ground prong could not have caused this problem on a properly wired system. That or his monitor is measuring voltage to ground instead of the neutral bus.
Justin & Cathy Byrd
1995 U280 "Old Faithful"
36' Build #4673
C8.3 Cummins
Allison MD3060R 6 speed - retarder
Powertech 10KW  4cyl Kubota
 

Re: Voltage Problem

Reply #38 –
The factory power line monitor sometimes shows the same voltages as Glenn saw, on our coach. It seems to just be the monitor as none of the voltages are off at the outlets. Next time I plug in it is back to normal.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean