I purchased four of these 100 watt panels from Home Depot.https://www.homedepot.com/p/Grape-Solar-100-Watt-Polycrystalline-Solar-Panel-for-RV-s-Boats-and-12-Volt-Systems-GS-Star-100W/204211365I figured at 89 cents per watt and free shipping it was time to buy.Now I need the other necessary components such as a 40 amp or larger MPPT controller, wiring, and mounting.Primarily I am looking for controller recommendations as I am overwhelmed with all the available options.Any advice on wiring and mounts would also be appreciated.Two panels will be mounted in one area and two panels in another. Because of that I am thinking each pair in series and the two pairs in parallel unless there is good reason not to do so.I currently use four gel batteries for 300AH but might be switching to four golf car batteries for a total of 440AH.

I recommend the Morningstar TS-MPPT-30 but at close to $400 there are lower cost controllers around. I don't think you need more than 30 amps. That is I would not pay extra for 40 unless you may expand the system. I bought the 60 and in hindsight the 45 would have been fine.https://www.morningstarcorp.com/products/tristar-mppt/Amazon TS-MPPT-30 $382

Series is easier. Gel batteries, really?

Each panel can do about 6.2 amps in direct sun but yours will be flat so get less. Even at max you get 25 amps, so a 30 amp controller is enough, allowing the necessary margin for cold temps.MPPT is not going to do much better, if any better than PWM for your array. BTDT measured it. So you could have picked up that 40 amp Grape controller while you were at it. Some forum members have that controller and are pleased with them. You would put all four in parallel in that case, but no big deal.

Hi Time2roll,The Morningstar MPPT 60 does have some advantages--it is essentially three controllers "stacked" together, so it is more efficient at low amperage than the 45.I made the mistake of only getting a 30 amp controller, that meant upgrading meant buying either an additional controller--or buying a larger one. I've not done either because of the cost.time2roll wrote:I recommend the Morningstar TS-MPPT-30 but at close to $400 there are lower cost controllers around. I don't think you need more than 30 amps. That is I would not pay extra for 40 unless you may expand the system. I bought the 60 and in hindsight the 45 would have been fine.https://www.morningstarcorp.com/products/tristar-mppt/Amazon TS-MPPT-30 $382

Hi beemerphile1,I'm glad you found some excellent panels.Minimum standard for the controller would have adjustable voltage set points and a temperature probe on the battery bank. A nice upgrade to that is having voltage sense wires so that smaller wire may be used between the controller and the battery bank.I would buy a controller that allowed room for expansion. i.e. adding more panels.

MPPT controller recommendations | Good Sam Community

TUCQUALA
Explorer
May 11, 2018
Look at the EPSolar (EPEver) 40A MPPT controllers. Really nice units with lots of adjustments. And not out of line on price for most of us!!!

https://www.rv.net/forum/index.cfm/fuseaction/thread/tid/29522581/srt/pa/pging/1/page/1.cfm
MrWizard
Moderator
May 11, 2018
my '2 cents' the grape solar 40 amp PWM controller
wire the panels in parallel
its a great controller
fully configurable for all voltage points
even time in bulk
and voltage recover/restart points
and it has bluetooth built in and run the app on your phone or tablet
to control settings and monitor the panels
and a fantastic value at approx $50-$60
brulaz
Explorer
May 11, 2018
time2roll wrote:
pianotuna wrote:
Minimum standard for the controller would have adjustable voltage set points and a temperature probe on the battery bank.
I also recommend a controller that automatically adjusts absorption time based on charge level.

Now that gets pricey. But the Bogart PWM SC-2030 combo with it's Trimetric Ah meter and shunt is nice and prolly the cheapest with this feature. The idea here is to limit over-charging your lead acids. But not sure how much of a problem that really is. Under-charging seems to be a bigger problem.

As for a relatively cheap MPPT controller with temp probe and adjustable everything, I'm happy with my EpSolar Tracer.
time2roll
Nomad
May 11, 2018
pianotuna wrote:
Minimum standard for the controller would have adjustable voltage set points and a temperature probe on the battery bank.
I also recommend a controller that automatically adjusts absorption time based on charge level.
pianotuna
Nomad III
May 11, 2018
Hi beemerphile1,

I'm glad you found some excellent panels.

Minimum standard for the controller would have adjustable voltage set points and a temperature probe on the battery bank.

A nice upgrade to that is having voltage sense wires so that smaller wire may be used between the controller and the battery bank.

I would buy a controller that allowed room for expansion. i.e. adding more panels.
pianotuna
Nomad III
May 11, 2018
Hi Time2roll,

The Morningstar MPPT 60 does have some advantages--it is essentially three controllers "stacked" together, so it is more efficient at low amperage than the 45.

I made the mistake of only getting a 30 amp controller, that meant upgrading meant buying either an additional controller--or buying a larger one. I've not done either because of the cost.

time2roll wrote:
I recommend the Morningstar TS-MPPT-30 but at close to $400 there are lower cost controllers around. I don't think you need more than 30 amps. That is I would not pay extra for 40 unless you may expand the system. I bought the 60 and in hindsight the 45 would have been fine.

https://www.morningstarcorp.com/products/tristar-mppt/

Amazon TS-MPPT-30 $382
BFL13
Explorer II
May 11, 2018
Each panel can do about 6.2 amps in direct sun but yours will be flat so get less. Even at max you get 25 amps, so a 30 amp controller is enough, allowing the necessary margin for cold temps.

MPPT is not going to do much better, if any better than PWM for your array. BTDT measured it. So you could have picked up that 40 amp Grape controller while you were at it. Some forum members have that controller and are pleased with them. You would put all four in parallel in that case, but no big deal.
2oldman
Explorer II
May 11, 2018
Series is easier. Gel batteries, really?
time2roll
Nomad
May 11, 2018
I recommend the Morningstar TS-MPPT-30 but at close to $400 there are lower cost controllers around. I don't think you need more than 30 amps. That is I would not pay extra for 40 unless you may expand the system. I bought the 60 and in hindsight the 45 would have been fine.

https://www.morningstarcorp.com/products/tristar-mppt/

Amazon TS-MPPT-30 $382

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