I have 4 solar panels on the roof

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Alpena Jeff

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Joined
Dec 7, 2014
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965
Location
Up North - Michigan
40"x21" each or so, thin flexible panels. No brand name that I can see. No Trimetic. Currently plugged into 15 amp shore power coming out of pole barn. 4 6v interstate deep cycle batteries. Panel from Newmar shows float charge, 13.6 volt D.C. I don't know if there's a question in here somewhere, thoughts on what I'm seeing?
Sun coming overhead soon, should I unplug from shore power and see what display panel says?
Thanks all.
Jeff
 
  Not sure exactly what controller you have (what readouts you can see), but.... it certainly wouldn’t hurt to know what the panels are doing! Though, if  System is “fully” charged, you won’t see what the panels “ can do”!  Use up some battery, and then see how they’er doing.

    On our monitor we can monitor input, output,etc.
 
you don't need to unplug.  the controllers know when to stop charging.
 
The 13.6 shows the float charge you are getting from your shore power. The solar won't do anything as long as you are plugged in. If you want to test your solar system unplug the shore for a day.
 
Sprucegum said:
... The solar won't do anything as long as you are plugged in...

That is not accurate in all situations.  I have my solar controller on even when I am plugged into shore power.  MY onboard charger maxes out at 14.4 volts, so my solar controller will take over and charge the batteries up to 14.8 volts to fully charge them.
 
Alpena Jeff said:
40"x21" each or so, thin flexible panels. No brand name that I can see. No Trimetic. Currently plugged into 15 amp shore power coming out of pole barn. 4 6v interstate deep cycle batteries. Panel from Newmar shows float charge, 13.6 volt D.C. I don't know if there's a question in here somewhere, thoughts on what I'm seeing?
Sun coming overhead soon, should I unplug from shore power and see what display panel says?
Thanks all.
Jeff
Yes, you should disconnect from shore power while the sun is shinning during mid day and see what the panel shows.  You should see 13.4V or higher. 

For a test, unplug from shore power in the early evening after the sun is off of your solar panels.  Turn on 2-3 lights, if you have LED lights turn them all on.  Leave them on for an hour or two.  Your battery voltage should not drop below about 12.5V or so. (If the voltage drops to 12.2V in an hour or two you have weak batteries.) Turn the lights off & anything else that uses 12V for the night. (you can leave the propane fridge on)  Come back in the morning before the sun hits the panels and check the voltage.  Around 10am check the voltage, it should be a charging voltage. 

Let us know the results and we can go from there.

If you don't have a lot of experience with RV electric systems, here are two links to great info about RV elect:
http://www.marxrv.com/12volt/12volt.htm
http://www.marxrv.com/12volt/12volta.htm
 
Thank you for this post. I am about to move into my 2016 5th wheel that is wired for solar.  A bit down the road I plan on getting solar installed once life settles down a bit, get 5th wheel hitch installed in bed of pick up, get 5th wheel parked end of this month at RV resort I just put deposit down.   
 
AStravelers said:
Yes, you should disconnect from shore power while the sun is shinning during mid day and see what the panel shows.  You should see 13.4V or higher. 

For a test, unplug from shore power in the early evening after the sun is off of your solar panels.  Turn on 2-3 lights, if you have LED lights turn them all on.  Leave them on for an hour or two.  Your battery voltage should not drop below about 12.5V or so. (If the voltage drops to 12.2V in an hour or two you have weak batteries.) Turn the lights off & anything else that uses 12V for the night. (you can leave the propane fridge on)  Come back in the morning before the sun hits the panels and check the voltage.  Around 10am check the voltage, it should be a charging voltage. 

Let us know the results and we can go from there.

If you don't have a lot of experience with RV electric systems, here are two links to great info about RV elect:
http://www.marxrv.com/12volt/12volt.htm
http://www.marxrv.com/12volt/12volta.htm
Been unable to test as we haven't seen the sun in a week! Stay tuned....
 
Ok. When plugged into 15 amp shore power my display showed 13.6-13.8 volt. Took off shore power and after 90 minutes display shows 12.2 volt. Had inside led lights on and 2-way fridge on switched to ac power.
This sounds like week batteries right! This is a 2016 model year with 15k miles.
Also, been raining for days so no solar assist.
 
It is difficult to know what you are seeing.  The 13.6 to 13.8 volts you were seeing is the charger voltage, and not the true battery voltage. Were your batteries fully charged before unhooking from shore power?  Does your onboard charger have the capability to fully charge your batteries?  I believe some Interstate deep cycle batteries need to see 15.3 volts for a period of time to be fully charged.  How many amps does your refrigerator draw when on electric?  Also, with a load on battery voltage will show less than the true voltage of the battery.  Hopefully, those with more knowledge that I, will come along and provide more information.
 
Suspicious to be sure, but as Paul & Ann noted, there are too many unanswered questions to draw any real conclusions.  The fridge alone could account for a substantial draw on the batteries if it the cooling unit run non-stop for 90 minutes (likely).

Another factor: how many and what size batteries are involved?  I'm guessing at least 200-230 AH of battery capacity, but it could be 2x that.
 
We have 4 Interstate deep cycle @ 232ah each and a Magnum ME 2000 Series MSW inverter/charger if that helps.
I have a lot to learn about this stuff!
 
First-- Do you have a Magnum ME 2000 or the Magnum ME 2012 inverter charger?  I am unable to find a ME 2000 inverter on an internet search. 

Second--  How long were you plugged into the 15amp shore power?  Even though you have a 100amp 3 stage charger, it still takes 6 to 12 hours to get your batteries fully charged. 

Third--  You say you turned your gas elect fridge to elect after you disconnected from shore power.  Are you really sure the fridge was actually working on elect.  Gas/elect fridge's should not be wired through the inverter.  All these fridges I know of only have 3 power settings, Off, Gas only, and Auto.  If the fridge is on the auto setting, it will default to gas if there is no 120V AC present, which there should not be if not plugged into shore power and the generator is not running. 

As long as you were plugged into shore power long enough, 6-12 hours, to charge your batteries, they should not have dropped to 12.2V in 90 minutes. 

If your fridge indeed is wired though the inverter, do this test again and after 90 minutes turn off the fridge and check your voltage.  Having a load on your batteries will cause them to show a lower voltage than the batteries would at rest.  However the load from the fridge should not drop the voltage from the fully charged voltage of 12.6V to 12.2V in 90 minutes.  Not with over 400AH of battery.

Also as you noted, when connected to shore power you are seeing 13.6-13.8 volts.  When you disconnect from shore power you should still see the 13.6V for some few to several minutes.  It should then decrease to about 12.6V which is the voltage of a fully charged battery bank. 

If you continue seeing 12.2V you should take a multi meter, and check the voltages of your individual batteries.  I'm assuming you have four 6V deep cycle golf cart batteries.  You could have one bad battery.

Have you checked the water level in the batteries?  If the water level in any of the battery cells has dropped far enough to expose the plates to the air, that is likely the cause of your problems. 
 
AStravelers said:
First-- Do you have a Magnum ME 2000 or the Magnum ME 2012 inverter charger?  I am unable to find a ME 2000 inverter on an internet search. 

Second--  How long were you plugged into the 15amp shore power?  Even though you have a 100amp 3 stage charger, it still takes 6 to 12 hours to get your batteries fully charged. 

Third--  You say you turned your gas elect fridge to elect after you disconnected from shore power.  Are you really sure the fridge was actually working on elect.  Gas/elect fridge's should not be wired through the inverter.  All these fridges I know of only have 3 power settings, Off, Gas only, and Auto.  If the fridge is on the auto setting, it will default to gas if there is no 120V AC present, which there should not be if not plugged into shore power and the generator is not running. 

As long as you were plugged into shore power long enough, 6-12 hours, to charge your batteries, they should not have dropped to 12.2V in 90 minutes. 

If your fridge indeed is wired though the inverter, do this test again and after 90 minutes turn off the fridge and check your voltage.  Having a load on your batteries will cause them to show a lower voltage than the batteries would at rest.  However the load from the fridge should not drop the voltage from the fully charged voltage of 12.6V to 12.2V in 90 minutes.  Not with over 400AH of battery.

Also as you noted, when connected to shore power you are seeing 13.6-13.8 volts.  When you disconnect from shore power you should still see the 13.6V for some few to several minutes.  It should then decrease to about 12.6V which is the voltage of a fully charged battery bank. 

If you continue seeing 12.2V you should take a multi meter, and check the voltages of your individual batteries.  I'm assuming you have four 6V deep cycle golf cart batteries.  You could have one bad battery.

Have you checked the water level in the batteries?  If the water level in any of the battery cells has dropped far enough to expose the plates to the air, that is likely the cause of your problems.

Thanks for helping Al.
First. It is a 2012. Just confirmed

Second. Was plugging in for at least 12 hours, likely longer.

Third. Just unplugged after being plugged in overnight. Inverter off and fridge which is set at auto is now running on LP. I turned the inverter on and fridge switched to AC. Turned inverter off and back to LP.
Before unplugging meter showed 13.6-13.7 volt. After 30 minutes meter showing 12.7 volts.
Yesterday I had the inverter on and like I said the fridge showed AC. Maybe that drove the voltage down? It got to 11.7 before I plugged back in for the night.
My sales guy said to just leave the inverter on. Let it do its thing.

Did check water level in batteries and we're good. Right now I'm letting it sit with fridge on propane, nothing else on.
After reading my response to your questions should I switch back to inverter and run the test you suggested?

 
Update.
Last 5 hours I have had all led lights on, fridge off. Everything else off. Meter shows 12.4 volts. Solar might be helping some. Cloudy here but maybe some help?
Thanks.
 
Alpena Jeff said:
Thanks for helping Al.
First. It is a 2012. Just confirmed

Second. Was plugging in for at least 12 hours, likely longer.

Third. Just unplugged after being plugged in overnight. Inverter off and fridge which is set at auto is now running on LP. I turned the inverter on and fridge switched to AC. Turned inverter off and back to LP.
Before unplugging meter showed 13.6-13.7 volt. After 30 minutes meter showing 12.7 volts.
Yesterday I had the inverter on and like I said the fridge showed AC. Maybe that drove the voltage down? It got to 11.7 before I plugged back in for the night.
My sales guy said to just leave the inverter on. Let it do its thing.

Did check water level in batteries and we're good. Right now I'm letting it sit with fridge on propane, nothing else on.
After reading my response to your questions should I switch back to inverter and run the test you suggested?
Alpena Jeff said:
Update.
Last 5 hours I have had all led lights on, fridge off. Everything else off. Meter shows 12.4 volts. Solar might be helping some. Cloudy here but maybe some help?
Thanks.
Sorry for the late response.  Thanks for the great details about the problems you are seeing. 

Bottom line it sounds like you have weak batteries. 

--  No need to have the inverter on and the fridge on as a load for testing as I suggested. Your other tests showed what I was looking for.
--  Your report that after 5 hours with fridge & lights off and your batteries dropped to 12.4V.  That is not good if your batteries had been charged overnight. You could have weak batteries.  Possibly because they were discharged too low by the fridge running off the inverter.  It is possible you have something in the RV pulling 5 to 10 amps.  However with 400+ AH of battery that shouldn't drop your battery voltage to something like 12.4V in 5 hours. Especially if your batteries in good condition.  You would need a amp meter to check to be sure you don't have a phantom load someplace. 
-- Listened to your salesman, did you? Hmm.  :)  Well the salesman isn't totally wrong.  The inverter/battery setup works pretty good assuming you limit the time to being unhooked from shore power to 6-8 hours.  And if your batteries are new or in good condition.

Assuming your batteries are original they are now 5 years old and probably in need of replacement.  However if you always stay at places with elect hookups the batteries may last another couple of years.  That is as long as you are sure to have the fridge on propane while you are disconnected from shore power.

You are a good example on why RV mfg should not wire the gas/elect fridge through the inverter.  Disconnect from shore power for 24 hours and your batteries are toast unless you "always" remember to switch the fridge to gas only.  Some people absolutely will not travel with the propane on.  Having the fridge run through the inverter solves that issue.  In 40 years of traveling with RV's with propane and gas/elect fridge we have never turned off the propane while traveling.  (Well when on a ferry or some long tunnels when required to have the propane off)

Note: If you will be dry camping or boondocking for more that 1-2 days between connecting to shore power, you really need a battery monitor such as a Trimetric: http://www.bogartengineering.com/products/trimetrics/

BTW, did you recently buy this RV?

Hope this helps.

 
Alpena Jeff said:
40"x21" each or so, thin flexible panels. No brand name that I can see. No Trimetic. Currently plugged into 15 amp shore power coming out of pole barn. 4 6v interstate deep cycle batteries. Panel from Newmar shows float charge, 13.6 volt D.C. I don't know if there's a question in here somewhere, thoughts on what I'm seeing?
Sun coming overhead soon, should I unplug from shore power and see what display panel says?
Thanks all.
Jeff
With solar panels sized 40"x21" you probably have 80watts per panel, maybe as much as 100watts. 

320watts to 400watts of solar will keep your batteries pretty well charged as long as your dry camping requirement are not very high.  With 400AH of battery I would prefer 600watts or more. 

However if your fridge is running off the inverter for a 2-3 days of cloudy weather the panels won't keep up with the power draw.
 
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