Reply
 
Thread Tools Search this Thread Display Modes
 
Old 08-10-2016, 10:15 AM   #1
2 Rivet Member
 
Airboutique's Avatar
 
1972 25' Tradewind
Montrose , Colorado
Join Date: Oct 2008
Posts: 34
Images: 1
Does Univolt need battery to run 12 volt fixtures?

Clarification please. My 12 volt "fixtures" only work when I have a battery hooked up to the univolt. According to an electrician, the univolt doesn't need a battery if it is connected to the main power source. I can hear the univolt running when I have the breaker on but it will not power anything 12 volt.

Thanks for any input!
__________________

__________________
Airboutique is offline   Reply With Quote
Old 08-10-2016, 10:22 AM   #2
Rivet Master
 
1988 25' Excella
1987 32' Excella
Knoxville , Tennessee
Join Date: Oct 2010
Posts: 2,046
Blog Entries: 1
That is interesting. On my 1988 Excella I can run the 12 volt stuff without a battery. I do not like to do it because the battery serves to flatten out the spikes and make the voltage more uniform. But I did run it for a week or so last year before I realized I had not hooked the batteries back up. I disconnect them over the summer since we leave the trailer plugged in to run a dehumidifier.

Not sure what the battery isolator switch does. Have you checked to see what position it is in? Are you saying the 12 volt system works fine with a battery (charges) but no voltage withoot a battery?
__________________

__________________
Bill M. is offline   Reply With Quote
Old 08-10-2016, 10:30 AM   #3
1 Rivet Member
 
1972 Argosy 24
Jamestown , North Carolina
Join Date: May 2016
Posts: 5
It almost sounds like it might not be switching from Battery power back to 120V. When you have the battery out have you tried checking the cables from the univolt with a meter?
__________________
rhudson12 is offline   Reply With Quote
Old 08-10-2016, 12:23 PM   #4
Rivet Master
 
HowieE's Avatar
 
1991 34' Excella
Princeton , New Jersey
Join Date: Aug 2003
Posts: 6,681
Images: 12
Test for voltage on the output terminals of the univolt while the batteries are disconnected. If you have voltage at that point and no lights will work the univolt may not connected to the circuits. Look at the battery terminals to see if the connection was made at the terminals and is open when the batteries are disconnected. If there is no voltage the univolt be designed to shut off when there is no battery load sensed.

As mentioned incorrectly above there is no connection between the 12 volt and 120 volt systems. I would also look for another electrician.
__________________
WBCCI 12156 AIR 3144 WACHUNG TAC NJ6
2004 Excursion 4x4
1991 34 ft. Excella +220,000 miles, new laminated flooring, new upholstery, new 3200 lbs axles

HowieE is offline   Reply With Quote
Old 08-11-2016, 07:29 AM   #5
1 Rivet Member
 
1972 Argosy 24
Jamestown , North Carolina
Join Date: May 2016
Posts: 5
I'm sorry. I think I didn't explain myself well. The 120V supplies the power for the 12 Volt output from the univolt. It most likely goes through a transformer, bridge, and rectifier to produce the 12 volts. So it is connected to the circuitry for the 12v. My point was that when the 120v is connected, the battery is connected to a charging circuit that probably outputs something low, like 2Amps. When the 120V is disconnected, the univolt has to switch over to allow the battery to supply the voltage through the univolt to the 12 volt circuitry. If the switch is bad, that would only allow the battery to supply 12 volts. By removing the cables from the battery and testing with a meter while plugged into 120V, you can see if the univolt charging circuit is switching and supplying 12v to battery for charge. Just my two cents.
__________________
rhudson12 is offline   Reply With Quote
Old 08-11-2016, 07:55 AM   #6
Rivet Master
 
HowieE's Avatar
 
1991 34' Excella
Princeton , New Jersey
Join Date: Aug 2003
Posts: 6,681
Images: 12
Check this site for more info.

http://www.tompatterson.com/VAC/disc....php?936805560
__________________
WBCCI 12156 AIR 3144 WACHUNG TAC NJ6
2004 Excursion 4x4
1991 34 ft. Excella +220,000 miles, new laminated flooring, new upholstery, new 3200 lbs axles

HowieE is offline   Reply With Quote
Old 08-11-2016, 12:11 PM   #7
2 Rivet Member
 
1973 25' Tradewind
Redding , California
Join Date: Nov 2015
Posts: 42
Try This as well...

I have a 1973 tradewind. My univolt was doing the same thing, but it was also not charging the battery. When I took off the univolt cover it all made sense. There was a leakage and total corrosion of the converter.

It is really an easy fix to swap out the univolt for an upgraded 12v converter. I bought the boondocker from bestconverters.com and a new 12v distribution panel. It took about an hour to remove the univolt and install the boondocker. I have yet secure everything and tidy it up, but I had my 12v running smoothly in no time. If you have your manual, all the wires should be listed but even that is easy to figure out without it.

A couple benefits: The weight-the univlot is crazy heavy compared to the new technology. Better battery maintenance-the new converter is better at charging batteries. Sound-the new converters are quite a bit quieter.

Good luck!
__________________
Leadvox is offline   Reply With Quote
Old 08-11-2016, 12:26 PM   #8
Rivet Master
 
TG Twinkie's Avatar
 
1974 Argosy 26
Morrill , Nebraska
Join Date: Nov 2009
Posts: 5,000
Images: 2
Blog Entries: 5
The Univolt does not "switch over" it is on continuously as long as there is 120 volt power to it. It is wired in parallel with the battery and the 12 volt fuse panel.
If you don't have lights without the battery but the battery is charging (which I doubt) you probably have a wiring problem, connection problem or maybe a blown fuse.
The Univolt will provide power without the battery but it is not regulated well and the power could vary from 13 to 15 volts.
__________________
Knowledge: "A gift to be shared. A treasure to receive."
TG Twinkie is offline   Reply With Quote
Old 08-11-2016, 01:08 PM   #9
4 Rivet Member
 
1973 31' Sovereign
Middletown , California
Join Date: Oct 2015
Posts: 400
When my Univolt did that it was because one of the capacitors went bad. Watch out, 500V on those capacitors! The Univolts are tough but awful noisy, the Capacitors and the fuse panels are what usually quits on them. After replacing a bad capacitor twice I removed the Univolt and replaced it with a solid state power supply, much quieter but easy to kill with generator power malfunction. I kept the fuse panel from the Univolt so I could have the Amp meter function in the control center and it was still in good shape.
__________________
ijustlee is offline   Reply With Quote
Old 08-11-2016, 02:05 PM   #10
3 Rivet Member
 
GR8DANE's Avatar
 
1966 22' Safari
1964 24' Tradewind
1956 18' "Footer"
Southern , Minnesota
Join Date: Oct 2008
Posts: 118
Go fishing, use univolt as anchor, unplug first.
__________________
GR8DANE is offline   Reply With Quote
Old 08-11-2016, 03:42 PM   #11
Rivet Master
 
A W Warn's Avatar
 
2000 25' Safari
1999 34' Excella
Davidson County, NC , Highlands County, FL
Join Date: Aug 2006
Posts: 2,407
Quote:
Originally Posted by Airboutique View Post
Clarification please. My 12 volt "fixtures" only work when I have a battery hooked up to the univolt. According to an electrician, the univolt doesn't need a battery if it is connected to the main power source. I can hear the univolt running when I have the breaker on but it will not power anything 12 volt.

Thanks for any input!
Isn't there an external fuse on the converter?

I know that those older units are supposed to only be run with a battery connected or they might be damaged. What brand/manufacturer do you have?
__________________
Alan
2014 Silverado 1500 Crew Cab 5.3L maximum trailering package (yes, I'm towing the 34')
A W Warn is offline   Reply With Quote
Old 08-11-2016, 03:59 PM   #12
2 Rivet Member
 
1973 25' Tradewind
Redding , California
Join Date: Nov 2015
Posts: 42
Quote:
Originally Posted by GR8DANE View Post
Go fishing, use univolt as anchor, unplug first.
Be careful it doesn't sink your boat.
__________________
Leadvox is offline   Reply With Quote
Old 08-12-2016, 01:46 AM   #13
4 Rivet Member
 
1973 31' Sovereign
Middletown , California
Join Date: Oct 2015
Posts: 400
Yes. A W Warn, In my '73 I think there is a 50 Amp fuse in the black - wire that connects to the Univolt. It may go to the - battery terminal but I can't remember. Worth checking all fuses for sure. An old blue Univolt will run the lights and furnace without a battery and shouldn't hurt anything. They will overcharge a battery and I believe Airstream was paid by a battery manufacturer to install these Univolts so they were guaranteed repeat battery sales!
__________________
ijustlee is offline   Reply With Quote
Old 08-12-2016, 07:32 AM   #14
4 Rivet Member
 
1967 26' Overlander
Spartanburg , South Carolina
Join Date: Jan 2011
Posts: 385
One of the best things to happen to my '67 Overlander was when the original Univolt quit working. I replaced it connection for connection with an Intellipower 9100 converter by Progressive Dynamics which so far has been flawless. it uses less power itself and takes up less space. When it failed in warranty, PD replaced it at no charge with an upgraded model. I've never tried to operate w/o a battery. The main function of the battery when on shore power is to act as a buffer to eliminate spikes and dips in voltage.
__________________

__________________
Jacob D is offline   Reply With Quote
Reply

Tags
12 volt


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
Plugged into 120 volt... What can I run? Plasma800 Electrical - Systems, Generators, Batteries & Solar 19 12-29-2015 06:05 PM
OK to Run AC on house 110 volt? Chasmorgan Furnaces, Heaters, Fireplaces & Air Conditioning 9 06-30-2009 08:03 AM
Wiring Sequence to hook up 2 x 6 volt battery pack to your 12 volt trailer battery TobyJH Batteries, Univolts, Converters & Inverters 0 05-21-2004 12:04 AM


Virginia Campgrounds

Reviews provided by



Our Communities

Our communities encompass many different hobbies and interests, but each one is built on friendly, intelligent membership.

» More about our Communities

Automotive Communities

Our Automotive communities encompass many different makes and models. From U.S. domestics to European Saloons.

» More about our Automotive Communities

Marine Communities

Our Marine websites focus on Cruising and Sailing Vessels, including forums and the largest cruising Wiki project on the web today.

» More about our Marine Communities


Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 08:46 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.

Airstream is a registered trademark of Airstream Inc. All rights reserved. Airstream trademark used under license to Social Knowledge LLC.