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Ok to run shore power without battery?

144Grayling
Explorer II
Explorer II
I have a 2007 Komfort trailer with a WFCO ultra distribution panel model WF8955an with a 3 stage converter. Lately the fan in the panel has started running for hours at a time. I checked the battery and it is boiling HOT. We don’t travel, the trailer is plugged into shore power 100% of the time. Is there any problem with removing the battery and just having the 12v lights and bath fan run off the converter?
49 REPLIES 49

2112
Explorer II
Explorer II

I have a WFCO 8935 that was boiling my batteries. The camper has been plugged in 24/7 with the battery disconnected for over a year without issue.

I'll connect the battery if I need to open/close the slides or operate the landing gear.

2011 Ford F-150 EcoBoost SuperCab Max Tow, 2084# Payload, 11,300# Tow,
Timbrens
2013 KZ Durango 2857

opnspaces
Navigator II
Navigator II

What post am I missing here? Is there a post saying he has 16+ volts or something? How is 12.9 or 13.2 dangerous to the equipment on his RV? Doesn't every RV when plugged in have 13+ volts and 14+ in boost mode?

.
2001 Suburban 4x4. 6.0L, 4.10 3/4 ton **** 2005 Jayco Jay Flight 27BH **** 1986 Coleman Columbia Popup

MNtundraRet
Navigator
Navigator

I do not know where you came up with your crazy ideas. I have been camping for over 50 years.  None of this is safe for the equipment on RV's of any sort. 

Mark & Jan "Old age & treachery win over youth & enthusiasm"
2003 Fleetwood Jamboree 29

JimmyG_The_One
Explorer
Explorer

Battery has nothing to do with this. 

You either have a 12V load that is too high or your converter is having problems.

Also your battery is meant for travelling and short term power. If you have a battery disconnect, I would recommend shutting it off while connected to shore power. 

Have you had any recent modifications? (A 12v fridge will do this.)

MrWizard
Moderator
Moderator

Problem Yes.

Because the converter is malfunctioning , the voltage us too high, running from the converter only is going damage the control boards for the fridge, air condition, heater, water heater , maybe burn out your water pump and vent fans, replace your converter, without a battery what will you do if shore power fails,  everything will turn off , no heat, no water, no lights, even the fridge b will turn off 

I can explain it to you.
But I Can Not understand it for you !

....

Connected using T-Mobile Home internet and Visible Phone service
1997 F53 Bounder 36s

time2roll
Nomad
Nomad

StirCrazy
Navigator
Navigator
144Grayling wrote:
Ok. I checked the converter output this morning and it’s 13.2 VDC So it’s in float mode.


with a battery or without. if without it still isn't right and it won't go into any "Mode" without a battery connected as it is the state of charge of the battery that determines the load, or time at that state of charge. If this is with a battery you could be good. without. still doesn't meet specs.
2014 F350 6.7 Platinum
2016 Cougar 330RBK
1991 Slumberqueen WS100

ScottG
Nomad
Nomad
144Grayling wrote:
Ok. I checked the converter output this morning and it’s 13.2 VDC So it’s in float mode.


Perfect.

144Grayling
Explorer II
Explorer II
Ok. I checked the converter output this morning and it’s 13.2 VDC So it’s in float mode.

Boon_Docker
Explorer II
Explorer II
ktmrfs wrote:
Boon Docker wrote:
His 12.9v reading from the converter (with no battery) is 14.32v RMS.


how do you know that? If the converter is putting out 12.9V DC with little or no ripple the RMS voltage is 12.9V

Unless you LOOK at the output waveform and KNOW what kind of meter is used you don't know what the RMS value is.


Epistemology :B

StirCrazy
Navigator
Navigator
wa8yxm wrote:


I'd need to haul some serious test gear into his rig to make an "Diagnosis" but.


so his 12 volts... might just be poor filtering of a supply with lots of ripple. Or it may be a very smart converter that says "Well I do not sense a battery so I'll go with the lower voltage"



not really a simple multimeter would do, if you really wanted to see a wavelength a simple oscilloscope will work.

He told us the model number and that's what that converter is supposed to put out as an output, from the manufacture, with no battery. We are not talking generics here but rather an actual test procedure from the manufacturer for that model.

but why the heck are we talking about RMS here, that is to get the average power from an ac power form and compare it to a DC voltage, there is no DC RMS, we do get DC ripple that is introduced from components and old unfiltered systems when they are plugged in or failing but that usually presents as a higher or lower overall voltage, and same thing you need a oscilloscope to see the ripple, so a manufacture isn't going to use that as a simple test the consumer can do as while you don't need an expensive one not many people have purchased a oscilloscope for their home tool box.
2014 F350 6.7 Platinum
2016 Cougar 330RBK
1991 Slumberqueen WS100

144Grayling
Explorer II
Explorer II
According to the operators manual the power converter has 3 modes: bulk, absorption and float. If the output voltage of the battery drops to 13.2 it goes into bulk mode and puts out 14.4 VDC. When the battery reaches 14.4 or after 4 hours, (whichever comes first) it reverts to absorption mode (13.6 VDC). After detecting no load for 48 hrs the converter goes into float mode (13.2).
Notice that none of the modes put out 12.9, so yes it’s probably defective. But as I said above, everything I need 12 volts for is working fine so I’m just going to live with it. I never timed how long I heard the cooling fan running (which I guess was bulk mode) but it seemed like more than 4 hrs. However long it ran, it boiled the battery. Maybe because the battery never got to 14.4 and the converter kept trying, possibly longer than it should have.
There is a caution in the manual that if it cycles into bulk mode more than once during a charge cycle to check for a bad battery. I wasn’t paying good attention and should have done that. And timed the bulk mode. And of course I shouldn’t have left the battery outside uncharged for 2 winters. So I lost all kinds of points on this one. As long as it’s not going to drive the converter crazy with zero volts battery discharge and damage it to the point it doesn't put out 12 volts, I can live with it. And as long as it’s not going to burn the trailer down trying to charge an air gap.

ktmrfs
Explorer
Explorer
Boon Docker wrote:
His 12.9v reading from the converter (with no battery) is 14.32v RMS.


how do you know that? If the converter is putting out 12.9V DC with little or no ripple the RMS voltage is 12.9V

Unless you LOOK at the output waveform and KNOW what kind of meter is used you don't know what the RMS value is.
2011 Keystone Outback 295RE
2004 14' bikehauler with full living quarters
2015.5 Denali 4x4 CC/SB Duramax/Allison
2004.5 Silverado 4x4 CC/SB Duramax/Allison passed on to our Son!

Boon_Docker
Explorer II
Explorer II
His 12.9v reading from the converter (with no battery) is 14.32v RMS.