Hello everyone and thanks for having such a great forum. This is my first post though I have been trolling and learning for some time now.I have a 34 Ft. Airstream Cutter with a Ford 460. I would love to install a solar panel system to charge the batteries. I have two 12V house batteries located inside the RV under the doghouse and one 12V battery under the "hood" that starts the RV. I would like to know that is use the TriStar MPPT 60, will I be able to use that controller to charge all three batteries or will I need two separate controllers one for house batteries and another for the engine's start-up battery? If I need two do I need MPPT for both (two Tristar MPPT 60)? Can I go with something more affordable with Tristar MPPT 30 or can I even use something like a Xantrex C35 charge controller for the truck battery?Frankly, I am electrically-challenged (flunked out of electrical engineering school) and I am super confused about this whole process.Thanks in advance,Peter

I use our solar system to charge both house and cranking battery. Installed a switch to de-energize the isolation relay between house and cranking battery that came with coach. I keep an eye on the house batteries charging current and when it starts to taper off I'll energize the isolation relay for 1 to 2 hours then drop it back out.

Morningstar makes the Sun Saver Dou controller is designed for charging two battery banks. The percentage of charge, going to each can be controlled.

I use a Amp-L-Start, my solar charges my two house batteries and the Amp-L-Start charges my chassis from house but will not discharge house. There is also the even cheaper Trick-L-Start for less amperage.There are also various BIRD's / ACR's that can combine house and chassis when sensing charge voltage on either side. I might switch over to a Blue Sea ACR at some point to replace the combiner solenoid and Amp-L-Start into one unit with manual override.

The Sun Saver Duo already mentioned is one way to do it, it has connections for two battery banks. However, it will not handle nearly the current of a TriStar MPPT 60 if you need that much current handling capacity.Another way to make this work is with a trick-L-start or amp-L-start. These would allow your house batteries, being charged by your TriStar, to also charge your chassis battery.Or, you could simply use most any voltage controlled relay or automatic charging relay to combine the banks when the voltage is high enough to provide a charge and disconnect them when it's not.

PeterCutter wrote:Hello everyone and thanks for having such a great forum. This is my first post though I have been trolling and learning for some time now.I have a 34 Ft. Airstream Cutter with a Ford 460. I would love to install a solar panel system to charge the batteries. I have two 12V house batteries located inside the RV under the doghouse and one 12V battery under the "hood" that starts the RV. I would like to know that is use the TriStar MPPT 60, will I be able to use that controller to charge all three batteries or will I need two separate controllers one for house batteries and another for the engine's start-up battery? If I need two do I need MPPT for both (two Tristar MPPT 60)? Can I go with something more affordable with Tristar MPPT 30 or can I even use something like a Xantrex C35 charge controller for the truck battery?Frankly, I am electrically-challenged (flunked out of electrical engineering school) and I am super confused about this whole process.Thanks in advance,Peter As explained there are other solutions out there. If you do not use or are careful about using the start battery then a Trik-L-Start would work. An Amp-L-start will output up to 15 amps and a Trik-L-Start will output up to 5 amps. This type of unit uses battery voltage to charge or disconnect the start battery. When I had a MH out of convenience I charged phone's and tablet's off the start battery and let the solar top it off the next day.

One Charge Controller for House and Start-up Battery??

scrubjaysnest
Explorer
Nov 26, 2016
I use our solar system to charge both house and cranking battery. Installed a switch to de-energize the isolation relay between house and cranking battery that came with coach. I keep an eye on the house batteries charging current and when it starts to taper off I'll energize the isolation relay for 1 to 2 hours then drop it back out.
harold1946
Explorer
Nov 26, 2016
Morningstar makes the Sun Saver Dou controller is designed for charging two battery banks. The percentage of charge, going to each can be controlled.
jharrell
Explorer
Nov 27, 2016
I use a Amp-L-Start, my solar charges my two house batteries and the Amp-L-Start charges my chassis from house but will not discharge house. There is also the even cheaper Trick-L-Start for less amperage.

There are also various BIRD's / ACR's that can combine house and chassis when sensing charge voltage on either side. I might switch over to a Blue Sea ACR at some point to replace the combiner solenoid and Amp-L-Start into one unit with manual override.
KD4UPL
Explorer
Nov 27, 2016
The Sun Saver Duo already mentioned is one way to do it, it has connections for two battery banks. However, it will not handle nearly the current of a TriStar MPPT 60 if you need that much current handling capacity.
Another way to make this work is with a trick-L-start or amp-L-start. These would allow your house batteries, being charged by your TriStar, to also charge your chassis battery.
Or, you could simply use most any voltage controlled relay or automatic charging relay to combine the banks when the voltage is high enough to provide a charge and disconnect them when it's not.
grizzzman
Explorer
Nov 27, 2016
PeterCutter wrote:
Hello everyone and thanks for having such a great forum. This is my first post though I have been trolling and learning for some time now.

I have a 34 Ft. Airstream Cutter with a Ford 460. I would love to install a solar panel system to charge the batteries. I have two 12V house batteries located inside the RV under the doghouse and one 12V battery under the "hood" that starts the RV.

I would like to know that is use the TriStar MPPT 60, will I be able to use that controller to charge all three batteries or will I need two separate controllers one for house batteries and another for the engine's start-up battery? If I need two do I need MPPT for both (two Tristar MPPT 60)? Can I go with something more affordable with Tristar MPPT 30 or can I even use something like a Xantrex C35 charge controller for the truck battery?

Frankly, I am electrically-challenged (flunked out of electrical engineering school) and I am super confused about this whole process.

Thanks in advance,

Peter

As explained there are other solutions out there. If you do not use or are careful about using the start battery then a Trik-L-Start would work. An Amp-L-start will output up to 15 amps and a Trik-L-Start will output up to 5 amps. This type of unit uses battery voltage to charge or disconnect the start battery. When I had a MH out of convenience I charged phone's and tablet's off the start battery and let the solar top it off the next day.
time2roll
Nomad
Nov 27, 2016
MS-MPPT-60 is great for 700 to 900 watts of solar panels. This is a bit large for two batteries. Not sure what you are contemplating however the 30 amp should be fine or you need to go 2X or 3X on battery capacity.

+1 for Trik-L-Start to maintain the chassis battery.
MrWizard
Moderator
Nov 27, 2016
Not that controller
Not in that manner, it would require jumpering the batteries together

Use a dual output controller
Or
Like many of us, some kind of trick l start
That siphons a small amount of power in a one way connection from house batteries to keep the engine batteries topped off
Ed_Gee
Explorer II
Nov 27, 2016
My BlueSky 3000i MPPT charge controller has a separate output to keep my start battery up. I would think other models and manufacturers would possibly have this option?
scrubjaysnest
Explorer
Nov 27, 2016
MrWizard wrote:
Not that controller
Not in that manner, it would require jumpering the batteries together

Use a dual output controller
Or
Like many of us, some kind of trick l start
That siphons a small amount of power in a one way connection from house batteries to keep the engine batteries topped off

Not sure I understand the comment about jumping the batteries together.
This is something already done any time the alternator output goes above some voltage set point, your on shore power and the converter output goes above the same set point, or your on the ginny and the converter output goes above the same set point. Set point voltage for ours is 13.2 volts after 2 1/2 minutes at or above that voltage.
Don't know if the OP's rv is set up that way or not.
time2roll
Nomad
Nov 27, 2016
Ed_Gee wrote:
My BlueSky 3000i MPPT charge controller has a separate output to keep my start battery up. I would think other models and manufacturers would possibly have this option?
The MS-MPPT-60 is network connectable and can control a relay driver or even send you an email when programmed.

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One Charge Controller for House and Start-up Battery??

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