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


Reply
 
Thread Tools Display Modes
 
Old 08-30-2015, 10:18 AM   #1
Junior Member
 
Join Date: Sep 2014
Location: SLC, UT
Posts: 4
Solar Causing Van Battery Drain?

Hey guys, long time listener, caller with an eletrical question.

I have a 2007 E350 SMB with a Blue Sky solar contoller and Surepower 1315-200 separator. My solar panels are not permanently mounted, so I can aim them, park in the shade, etc., so I'm pretty sure I've isolated this issue down to those times when I'm charging from solar.

A couple of times recently I've run my house battery down below 12.5 V, and have left my panels out to recharge with no load on the house side (no fridge, furnace, lights, everything off). After charging, usually for a full day, the van has started hard as if the van batteries are low.

I know that during these charging sessions the solar system is generating enough voltage to close the separator, so is it possible that during that time the house battery is drawing down my van batteries? Any help is much appreciated!

dogen is offline   Reply With Quote
Old 08-30-2015, 11:18 AM   #2
Site Team
 
daveb's Avatar
 
Join Date: May 2007
Location: Turlock Ca
Posts: 10,407
Garage
Re: Solar Causing Van Battery Drain?

When the separator closes during a solar charge does the voltage continue to rise to 13.4+ volts and higher? During the charge the separator should stay closed. If the separator closes and then opens it means you might have a bad starting (or house) battery or a unknown load somewhere provided the separator is working correctly.

So first I'd be suspect of a failing starting battery or even a poor battery connection somewhere. Is this a diesel rig? In some builds SMB configured the separator to automatically bridge the two battery systems during engine start. In later years SMB provided a push button switch so the owner has the option to make the jump assist combine the battery systems. It's an easy test to pull the ground wire off the separator which will disable it. Then if you start the van it will be forced to use the starting battery only for the test. If you keep the separator disabled, the house battery should stay at 12.8 for several days if there is no draw off it. If that battery continues to drop in voltage over the coarse of a few days, it's possible the house battery is bad. Always check all the connection first before replacing a battery.

I'm not saying there isn't an issue with the solar controller but from what I gather you're saying the panel charges up the house battery.
__________________
2006 Ford 6.0PSD EB-50/E-PH SMB 4X4 Rock Crawler Trailer

Sportsmobile 4X4 Adventures..........On and off road adventures
daveb is offline   Reply With Quote
Old 08-30-2015, 12:55 PM   #3
Junior Member
 
Join Date: Sep 2014
Location: SLC, UT
Posts: 4
Re: Solar Causing Van Battery Drain?

Thanks daveb, here's some more detail on my rig and what I'm seeing.

I do have a diesel rig, and the separator is wired to automatically jump the van batteries when started. I just removed that feature this morning, since I never really liked the idea of loading the house battery this way every time I turn the key. The separator seems to be working normally when I turn on shore power and after starting the van off of just the van batteries. The house battery (Lifeline 4D AGM) is less than a year old and will still hold 13+ V after a good charge.

The solar is successfully charging the house battery. When the solar charge closes the separator I see a slight dip in voltage, but it continues to rise as long as the sun is out. When the solar charge hovers right around 13.4 V the separator does cycle, which seems to be due to inconsistency of the panel output due to available sunlight.

All of the voltage data I have is from the digital display on the Blue Sky controller by the way.

I'm doing some testing today, but it looks like it might be a van battery issue, which is a bummer since I've replaced them within the last year as well. Hopefully it's just a bad connection somewhere.
dogen is offline   Reply With Quote
Old 08-30-2015, 02:34 PM   #4
Site Team
 
daveb's Avatar
 
Join Date: May 2007
Location: Turlock Ca
Posts: 10,407
Garage
Re: Solar Causing Van Battery Drain?

There are a few other things that can cause what you're seeing but generally that points to one of the starting batteries going bad. The only way to test that is to pull and test each battery on its own. If it's a bad starting battery many times you can feel the battery boxes and usually the bad battery will be warmer than its partner after a long drive or lengthy shorepower charge is applied. A poor connection won't cause that in most cases. Of coarse the separator must engage to charge off shore power. If the shore charger has limited amperage output, the separator may cycle open and closed on a constant basis. Same with solar...the house battery charges up but the bad battery pulls enough to drop the voltage below 12.8 and the separator opens. With the separator open, the bad starting battery robs its partner and they both go down together. A high impedance short can do the same.
FWIW AGM starting batteries seem to bank better together with the house system and at least in my case have out lasted the several wet cell types I lost on almost a yearly basis.

Hopefully you'll find it's just a bad battery connection...good luck
__________________
2006 Ford 6.0PSD EB-50/E-PH SMB 4X4 Rock Crawler Trailer

Sportsmobile 4X4 Adventures..........On and off road adventures
daveb is offline   Reply With Quote
Old 08-31-2015, 02:46 PM   #5
Senior Member
 
rockbender's Avatar
 
Join Date: Sep 2010
Location: Bend, OR
Posts: 800
Re: Solar Causing Van Battery Drain?

How much solar do you have? Keep in mind that when the SP1315-200 closes it is drawing nearly 1.5A. If you have a 100W panel, you might be getting 4A out of that, less 1.5A that it is taking to operate the separator solenoid. When I had a SP1315 I ended up wiring in a disconnect switch because I didn't want to use up any of my solar gain to simply operate the solenoid.

Also, if you house battery is low, the starter batteries are trying to equalize with it when the separator is closed.

Regardless of the above, I'd still lean towards Dave's assessment - check your terminals and then load test your starting batteries first to make sure you don't have one drawing the other one down. It sounds like you've got a classic case of a bad starting battery being masked by the house helping to turn the engine over.
__________________
Josh
2009 Express AWD, CCV Top & 50-ish home build. Daily driver/camper/kid hauler
rockbender is offline   Reply With Quote
Old 08-31-2015, 03:34 PM   #6
tlg
Senior Member
 
tlg's Avatar
 
Join Date: Aug 2013
Posts: 344
Garage
Re: Solar Causing Van Battery Drain?

I posted awhile back about successive clicks/cycling in my separator (SP Model 1315-200). Turns out it was a loose connection ((-) to the battery) on the back of the solar monitor. Guess it had worked its way loose over time. Before finding this, I spent a lot of time on the phone with Surepower and the solar folks (Zamp in my case) trying to resolve the issue. During the course of those conversations I learned that each separator has a click/cycle life (something like 50,000 cycles but don't recall the exact number). The take away for me was that the separator was eventually going to fail if the cycling kept up at the rate it was going. Cycle life becomes a problem when solar panels are operating under low light conditions. The panels generate just enough charge to open the separator and before you know it the light conditions change and the separator closes again. The cycle repeats itself far too often and does no good for the overall health of the system. Rockbender's decision to install a disconnect switch to this was a good one and I intend to do the same.
__________________
2014 Ford RB-50
tlg is offline   Reply With Quote
Old 08-31-2015, 07:13 PM   #7
Junior Member
 
Join Date: Sep 2014
Location: SLC, UT
Posts: 4
Re: Solar Causing Van Battery Drain?

Quote:
Originally Posted by rockbender
How much solar do you have? Keep in mind that when the SP1315-200 closes it is drawing nearly 1.5A. If you have a 100W panel, you might be getting 4A out of that, less 1.5A that it is taking to operate the separator solenoid. When I had a SP1315 I ended up wiring in a disconnect switch because I didn't want to use up any of my solar gain to simply operate the solenoid.

Also, if you house battery is low, the starter batteries are trying to equalize with it when the separator is closed.
I only have 60 W of solar, and after testing over the weekend, I think my system is spending a lot of time where the solar output is just enough to close the separator and equalize the house and van batteries.

Since the last hard start on Friday, my van has fired right up every time without the assist from the house battery. I'm still going to do some more testing on the van side, but I think I'm going to wire toggles for the separator and it's start assist feature.
dogen is offline   Reply With Quote
Old 08-31-2015, 07:43 PM   #8
Site Team
 
daveb's Avatar
 
Join Date: May 2007
Location: Turlock Ca
Posts: 10,407
Garage
Re: Solar Causing Van Battery Drain?

60 watts? That's not much and would be considered as more of a battery extender and that would be if it's pointed directly at the sun on a sunny day. But there are many times that my panels are only putting out a couple of amps and that still doesn't happen. In fact the separator is supposed to protect each battery system from each other. You really need to do a voltage check over the course of a few days to see what's up.

I'd do a full hard charge so both battery systems are fully charged, then pull the ground off the separator and let it sit for about 4 hours then record the voltages of both the starting and house batteries. Leave everything as is and let the batteries sit for a couple of days then check it again.

The house battery should register 12.7-12.8vDC and the starting batteries should be close to that maybe a little less. If the starting batteries drop below 12v you may have a problem somewhere. It would also be a good time to try and start the vehicle to see if it labors to crank. Silly things like leaving a glove box light on can bring down a battery quickly. Make sure the SMB radio switch is off, dome lights are off or any other thing that might be a draw. I had one of those under the hood emergency lights toggle on once in my pickup and I finally found it on only because I went out at night and saw light coming from the engine. My van doesn't have that; I'm only saying it might not be a battery issue and to look for the unexpected.

The detectors don't pull enough to draw down a battery over the course of a few days and the stock radio shouldn't either. Once the separator opens at 12.8 it also won't draw as much as when it is closed.
__________________
2006 Ford 6.0PSD EB-50/E-PH SMB 4X4 Rock Crawler Trailer

Sportsmobile 4X4 Adventures..........On and off road adventures
daveb is offline   Reply With Quote
Old 09-01-2015, 04:19 AM   #9
JWA
Senior Member
 
Join Date: Jan 2011
Location: Reynoldsburg, Ohio
Posts: 3,766
Send a message via Yahoo to JWA
Re: Solar Causing Van Battery Drain?

Quote:
Originally Posted by rockbender
How much solar do you have? Keep in mind that when the SP1315-200 closes it is drawing nearly 1.5A. If you have a 100W panel, you might be getting 4A out of that, less 1.5A that it is taking to operate the separator solenoid. When I had a SP1315 I ended up wiring in a disconnect switch because I didn't want to use up any of my solar gain to simply operate the solenoid.
When it comes to these devices using such a solenoid operating in this fashion is there no latching type switching device available that would eliminate that current draw?

(Just curious----seems like a lot of "wasted" power in this circumstance.)
JWA is offline   Reply With Quote
Old 09-01-2015, 07:30 AM   #10
Senior Member
 
Scalf77's Avatar
 
Join Date: May 2007
Location: Beaverton, OR
Posts: 2,490
Re: Solar Causing Van Battery Drain?

Yes, there is a latching device the Blue Sea 762X series. Since the OP has had the Surepower unit for a while, it would be a good candidate for the contact resistance issue. As tig said the units are good for 50,000 cycles, but the big issue is the solar charger would fall far short of meeting the minimal wetting current for such as large current solenoid. So over time the internal contacts build up resistance and cause a issue. If the OP has seen difficulty in charging the house batteries from the alternator that would be another symptom of the surepower unit going bad.

The surpower unit is suppose to take power for the solenoid off of which ever terminal has the higher voltage. The 1315 is bi-directional unit so which terminal you hook starter battery and house battery should not matter.

I guess it might be possible that the current to close the solenoid is coming from the starter battery or terminal that the starter is hooked to. With the contact resistance issue, enough current isn't passing through the solenoid and the current continues to draw from the starter. They could have designed around this, but in a working unit it would not mater.

If the Solar was able to bring the house batteries back up (which it sounds like it is) then it would be stronger data to support a bad 1315-200.

-greg
__________________
-greg
__________________________________________________ ______________
"Goldilocks" 2020 Ford Transit High Roof Extended 3.5 EcoBoost AWD Homebuilt
Scalf77 is online now   Reply With Quote
Reply

Thread Tools
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

» Featured Campgrounds

Reviews provided by

Powered by vBadvanced CMPS v3.2.3
Disclaimer:

This website is not affiliated with or endorsed by Sportsmobile SIP or any of its affiliates. This is an independent, unofficial site.


All times are GMT -6. The time now is 09:41 AM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2024, vBulletin Solutions, Inc.