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DC Electrical Problem?

At the camp ground I am staying at,  week at a time, I have noticed that the AC readout on the 'Powerwatch' meter varies between 118-124 or so volts.  I do have a shore line power protector, and it is showing a 'clean' power source with no fault indication.  Also, the Heart Interface link2000 panel is indicating that the charging of the batteries pretty much remain in the 'charge' mode and varies between 12.5 and 13.65 volts, it may get to the 'accept' mode, but hardly if ever gets to 'float'.  While at home, my shore line input is constant, and the charging routine seems normal, and will get into 'float'.  It seems like something is drawing on the battery while still being plugged into AC shore power at the campground. Causing the charging system to remain in 'charge' mode almost constantly.

Can someone explain to me what might be going on?  Do I have a problem that needs to be addresses?

Thanks, Mike
Mike Brady
'97 U320 SE. #5137
'13 Honda Fit
Willow Springs, MO

Re: DC Electrical Problem?

Reply #1 –
It sounds like you may having a dying house battery.  It's time to disconnect all the batteries and check voltage on each one.
Regards,
Brett

'99 42' Foretravel Xtreme
'14 Brown Motorsports Stacker
'05 Chevy SSR
'02 BMW R1150R

Re: DC Electrical Problem?

Reply #2 –
Is there any chance of a fire hazard?
Mike
Mike Brady
'97 U320 SE. #5137
'13 Honda Fit
Willow Springs, MO

Re: DC Electrical Problem?

Reply #3 –
Mike,

From your account in the first post, it sounds like the variable is the fact that you are "camping".  Charging "appears" normal at home - abnormal while at the camp ground.  Powerwatch voltage 118-124 (while camping) does not sound unusual to me.  So the question is, what do you do different while camping?  Answer: you use your 12 volt equipment.  The 12 volt power requirement while plugged in to shore power is generally served by the "converter" function of your inverter/charger.  Perhaps there is a malfunction in that circuitry?  If the converter is not providing direct 12 volt support, then the house batteries would carry the whole load.  This, in turn, would force the battery charger to continually replenish the batteries.  At home while parked, since you would not be using any 12 volt equipment, you might not see any evidence of this "missing" converter function.

That's my Sat. morning arm-chair analysis, for what it's worth.  Testing of each individual battery would still be a excellent investigative step, if only to reassure yourself of their functionality.  Also clean up your terminals while you're at it.  Never hurts!
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: DC Electrical Problem?

Reply #4 –
Mike,

Simple answer is yes, there is a danger of a fire, particularly if wet cell batteries.  When a cell dies, the inverter/charger continues to try to maintain the voltage it was told to produce.

So, if one cell is dead, it tries to charge a 10 VDC battery as if it were a 12 VDC battery.  That severely overcharges the remaining cells, causing lots of out-gassing with Hydrogen being produced.

Since these are the house batteries, you have more than one.  Try to isolate the bad one:  If wet cell, use a battery hydrometer (under $10 at any automotive store).  If AGM or Gel, look for swelling and/or excessive heat.  Short term, particularly if plugged into shore power is to remove that bad battery from the circuit.
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: DC Electrical Problem?

Reply #5 –
I have a similar problem in that the new house batteries will only indicate "READY" if plugged into shore power. 

We are in New England now and due to the hot temps have been running the generator and AC's almost constantly for the last 4 days while waiting for a RV site at a local park.

We were in a park plugged up to 30 amp service for 16 days just prior to arriving here at the Sam's Club parking lot and the "READY" light was on constantly.

Re: DC Electrical Problem?

Reply #6 –
Touch each battery, and see if any one of them feels hot or warmer than the others.  When my AGM batteries began to fail (from age), the failing batteries became very warm to the touch.  I isolated (disconnected)  the hot batteries until I was able to replace the entire set.

Quote from: Yetch –
Is there any chance of a fire hazard?
Mike
Dan - Full timing since 2009
2003 U320 40' Tag 2 slide

Re: DC Electrical Problem?

Reply #7 –
You may have a failing battery and that is certainly something to check.  But if you are at home and plugged in and it comes up to float with no significant 12 v loads and remains charging while on the road using lights and many other 12 v loads then it might just be that or your charger is not working well. But it should come up to float overnight.  Check and clean all of the battery posts and studs and cable ends. Make sure the connections are tight.  When you can get a load test on each battery.

In the mean time as has been suggested, remove connections from any suspect battery to be safe. And then work through the system one step at a time.  Do the safety stuff first then the simple stuff.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: DC Electrical Problem?

Reply #8 –
Quote from: Traveling Man –
I have a similar problem in that the new house batteries will only indicate "READY" if plugged into shore power. 

Xantrex Prosine 2.5 Inverter/charger?  (that was OEM)

If so, what lights are on for the Shore Power and Charger sections? (p. 38 of the following PDF, actual page 21 of the manual)

The selected media item is not currently available.
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: DC Electrical Problem?

Reply #10 –
Yetch wrote..  While at home, my shore line input is constant, and the charging routine seems normal, and will get into 'float'.

If he had a bad cell in a battery, as some have suggested, wouldn't the charger (convertor) act the same at home as it does on the road? The battery wouldn't reach full charge and float condition.

This doesn't sound like a bad battery situation to me. JMO
2003 GV320 4010

Re: DC Electrical Problem?

Reply #11 –
The inverter doesn't know or care where the 240VAC is coming from............which adds to the mix.

Yetch, just for fun.......... what happens when you're generator provides power?

Re: DC Electrical Problem?

Reply #12 –
For troubleshooting a DC current clamp-on amp meter is very handy and I would recommend should be in everyone's tool kit.  These have come down in price and can be had for just over $30. This would help identify if there is a unusually high current draw when the "salesman" house switch is on.

DC clamp on current meter
Peter and Tammy Fleming
1991 U300 GV 40 - Sold, owned for 4 years
Downsized to Roadtrek Popular 210 class B

Re: DC Electrical Problem?

Reply #13 –
Yetch asked..    Can someone explain to me what might be going on?  Do I have a problem that needs to be addresses?

Two possible explanations ...  Other AC loads in the coach get priority for the AC current that is available. The charger is last in line to get available amps. So if you are running your air conditioners and other AC loads pretty much most of the time, your charger might not be operating at anywhere near maximum output.

If the battery temperature sensor was installed and is registering hot summer temperatures in an enclosed battery compartment, the charger would reduce the charge. At 122 F battery temperature, the charger will turn off.

The info is in the User Manual....great idea Michelle!
2003 GV320 4010

Re: DC Electrical Problem?

Reply #14 –
So far:  Battery temps are 89* f, 3 batts, general compartment temp is around 86.  Batteries are not 'warm' to the touch.  Freedom 25 unit is around 90 to 92 in front of unit.  Checking on generators' charging now.
Mike
Mike Brady
'97 U320 SE. #5137
'13 Honda Fit
Willow Springs, MO

Re: DC Electrical Problem?

Reply #15 –
Using generator only, no difference in charging process.  It is beginning to seem to me that the converter is keeping the batt voltage at around 12.8. I am turning consumers off and on and am getting voltage drops and recovery back to that voltage.  But the charginging process doesn't want to go over 12.9, and remains in the charge mode.  But when I turn off all lights and everything inside the coach that I think would be using DC, the Link 2000 is indicating a 2amp draw.This morning something interesting happened:  AC voltage stopped inside coach, but I still had an indication with voltage protector that I use that there was service going into the coach.  I turned the gen set on, got AC back; turned gen set off, and shore line AC was back supplying power. 
I guess my question is what device is controlling this logic?  Could it be the Freedon 25?  Is the Isolator involved?
Mike
Mike Brady
'97 U320 SE. #5137
'13 Honda Fit
Willow Springs, MO

Re: DC Electrical Problem?

Reply #16 –
Quote from: Yetch –
But when I turn off all lights and everything inside the coach that I think would be using DC, the Link 2000 is indicating a 2amp draw.

This morning something interesting happened:  AC voltage stopped inside coach, but I still had an indication with voltage protector that I use that there was service going into the coach.  I turned the gen set on, got AC back; turned gen set off, and shore line AC was back supplying power. 
I guess my question is what device is controlling this logic? 

Mike,
That 2 amp draw could be a combination of the fridge electronics, clock over your bed, radio in your night stand, and all the little switch indicator lights. So, did you have the fuses pulled on these items and not just turned off?  Ours runs at about 1.5- 1.7

That problem seems like your shore/generator transfer switch is not swapping properly.

Pamela & Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: DC Electrical Problem?

Reply #17 –
Mike,

Let's back up a bit.

Since you mention the Heart Interface, I ASSUME you have the Xantrex Freedom inverter/charger.

If so, confirm that connections are clean and tight at batteries and at the inverter/ charger.

Then verify that the inverter/charger is properly programmed (battery technology, battery bank size in amp-hrs and temperature if you do not have the optional battery temperature sensor).

It should float around 13.2-13.6 depending on battery technology and ambient temperature.
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: DC Electrical Problem?

Reply #18 –
Thanks for the input.  Won't be able to get back to the coach till after 7pm.  What is throwing me off is the AC disconnect that I experienced this morning, and it may have happened sometime yesterday as when I got back to the coach last evening, I had had an AC interruption also, but it had recovered.
Mike
Mike Brady
'97 U320 SE. #5137
'13 Honda Fit
Willow Springs, MO