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RVing message boards => Tech Talk => Topic started by: jves on September 18, 2017, 06:45:10 PM

Title: Switching Off (Disabling) Solar Panels
Post by: jves on September 18, 2017, 06:45:10 PM
Would it be advisable to switch off my roof top solar array (400W) when under way or in a
full hookup situation when solar energy is not needed? The controller is a Morningstar
MPPT 40 amp.
Many thanks for any info.
Title: Re: Switching Off (Disabling) Solar Panels
Post by: HueyPilotVN on September 18, 2017, 06:49:14 PM
No need to do that,

The solar charging is in parallel to what ever else is charging, ( alternator, generator, shore power) and it will not hurt it to continue charging.

Free power to keep you topped off.
Title: Re: Switching Off (Disabling) Solar Panels
Post by: taoshum on September 18, 2017, 10:11:19 PM
No need to do that,

The solar charging is in parallel to what ever else is charging, ( alternator, generator, shore power) and it will not hurt it to continue charging.

Free power to keep you topped off.


not only "free" but less CO2 dumped into the atmosphere...
Title: Re: Switching Off (Disabling) Solar Panels
Post by: kdbgoat on September 19, 2017, 06:03:35 AM
And there's a good chance that Morningstar does a better job at topping off the batteries than anything else you have hooked to them for charging.
Title: Re: Switching Off (Disabling) Solar Panels
Post by: Paul & Ann on September 19, 2017, 10:06:49 AM
 :))
Title: Re: Switching Off (Disabling) Solar Panels
Post by: captaindomon on September 19, 2017, 10:25:59 AM
And with lead acid batteries you want to keep them topped off all the time anyway, to preserve battery life. So keeping it turned on is like taking care of your batteries.
Title: Re: Switching Off (Disabling) Solar Panels
Post by: ArdraF on September 19, 2017, 03:37:15 PM
When I saw your subject line I thought "why on earth would he want to do that?"  I don't believe we've ever even thought of disabling the solar panel because it's what trickle charges the battery to keep it "up."  You don't want your batteries to run down because it lessens their life span, especially if done frequently.  Even on somewhat cloudy days our solar panel display shows some charging.  Obviously it won't charge if covered with that white stuff that is a forbidden four-letter word [snow - shhh!] or on a rainy day, but otherwise keep it working for you and the benefit of your batteries.

ArdraF
Title: Re: Switching Off (Disabling) Solar Panels
Post by: TooTall on September 19, 2017, 08:31:18 PM
Would it be advisable to switch off my roof top solar array (400W) when under way or in a
full hookup situation when solar energy is not needed? The controller is a Morningstar
MPPT 40 amp.
Many thanks for any info.

Our system is set up so that if we are on shore power for we can disconnect the batteries and use the 55amp converter to power the trailer.  We have a battery charger that brings the batteries up to full charge and then turns off.  The charger keeps sensing the batteries and will top up when the batteries drop to 12.60VDC. 

You'll want to check the solar controller to see what the minimum charge  rate is and make sure that is below the self discharge rate of the battery bank.
Title: Re: Switching Off (Disabling) Solar Panels
Post by: jves on September 20, 2017, 06:01:31 PM
Thank you to all the Forum responders. In response to ArdraF question (why would any one want to do that) my reply
is that I don't want to over charge and shorten battery life. I checked my house batteries ( 2 Interstate deep cycle)  before
we left on our cross country trip and to my horror, found the cells to be dry! The batteries were abut 4 months prior. This                          is why I placed my question on the Forum.
Title: Re: Switching Off (Disabling) Solar Panels
Post by: ArdraF on September 21, 2017, 05:30:45 PM
Ah yes, now I understand.  Dry batteries definitely are a problem.  It's always a good idea to check batteries on a regular basis.  Just part of the regular maintenance program of a motorhome....

ArdraF