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Confused on what solar controller to purchase

mikiek

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Joined
Mar 23, 2022
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We have a large RV. It came with:
2x190w (GP-PV-190M) Go Power panels
30amp controller (GP-RVC-MPPT-30)
1,800W 12v inverter (PD1618)

We plan to boondock for several days at a time on private land (no power available).

We've purchased 2x304ah lithium batteries (4x304ah eve cells with a 100amp Jiabaida BMS) - 2 sets of these, giving us 608ah at 12v.

We also purchased 4x200w solar panels RS-M200D. I meant to order the 12v panels but was too late to cancel the order, so I've kept them.

The solar controller is outputting approximately 25amps (full midday sun) at 14v (350w), using the 4 Rich Solar Panels in series or parallel. I don't have the remote for the solar controller, and to cut a long story short, I cannot purchase one from the manufacturer as they were just bought out by another company and have minimum limits on spending, so refused to sell to me. I've tried everywhere to get one, as I think I could change settings to help improve performance?

So, I plan to replace this controller with another one. Perhaps Victron (if budget allows), or perhaps 2 smaller victron's if cheaper? One for the Rich Solar panels and the other for the go power panels.

I'm confused as to why my output didn't hit 30amps? If I purchase the Victron's, will this work, recharging at a faster rate (more amps output to the batteries)? And will I get closer to the possible output of almost 1200w?

Is 1200w too much for 12v? 100amps - my BMS can handle that, so I'm assuming that is ok (at a maximum).

I'm trying to figure out the best way forward without spending too much more on this project.

I've been told several times to go with 24v or 48v, but then I have to spend hundreds more on another inverter. I'd rather not do that. Also, I was never quite sure how I would get everything back down to 12v to supply all my 12v equipment in the RV.

Any help/thoughts are much appreciated.
 
Last edited:
We have a large RV. It came with:
2x190w (GP-PV-190M) Go Power panels
30amp controller (GP-RVC-MPPT-30)
1,800W 12v inverter (PD1618)

We plan to boondock for several days at a time on private land (no power available).

We've purchased 2x304ah lithium batteries (4x304ah eve cells with a 100amp Jiabaida BMS) - 2 sets of these, giving us 608ah at 12v.

We also purchased 4x200w solar panels RS-M200D. I meant to order the 12v panels but was too late to cancel the order, so I've kept them.

The solar controller is outputting approximately 25amps (full midday sun) at 14v (350w), using the 4 Rich Solar Panels in series or parallel. I don't have the remote for the solar controller, and to cut a long story short, I cannot purchase one from the manufacturer as they were just bought out by another company and have minimum limits on spending, so refused to sell to me. I've tried everywhere to get one, as I think I could change settings to help improve performance?

The controller will never put out more than 30A, so 30A * 14V = 420W is about your limit.

It's also limited to 100Voc, so 4S might not be an option.

If your battery is in absorption mode, it won't accept more current than it needs to maintain the absorption voltage.

So, I plan to replace this controller with another one. Perhaps Victron (if budget allows), or perhaps 2 smaller victron's if cheaper? One for the Rich Solar panels and the other for the go power panels.

I'm confused as to why my output didn't hit 30amps?

If your battery is in absorption mode, it won't accept more current than it needs to maintain the absorption voltage. Overcome this by inducing loads that you know are in excess of the array's power.
Flat panels on an RV roof rarely achieve rated power.

Are your 190W compatible with your 200W? Did you have them connected together?

GP panels:
Output power190 W
Rated current9.45 A
Rated DC voltage20.4 V
Open-circuit voltage24.09 V

Rich:
Maximum Power(Pmax)200W
Maximum Power Voltage(Vmp)37.6V
Maximum Power Current(Imp)5.36A
Open Circuit Voltage(Voc)45.4V
Short Circuit Current(Isc)5.83A

Not very compatible.

If you put these in series, the GP panels will be forced to operate at 5.63A instead of 9.45A

If your series voltage of parallel strings are not very close to each other, higher voltage panels will be dragged down to lower voltage panels.

If you put a Rich in parallel with the GP, you will force it to operate at around 20-24V instead of its ideal 37.6V - that's going to cut its output substantially.


If I purchase the Victron's, will this work, recharging at a faster rate (more amps output to the batteries)? And will I get closer to the possible output of almost 1200w?

It depends on how much money you can spend. 1200W implies you want to put all the panels. If you do, I'd put the 190W on one controller and the 200W on a different one.

380W/14V = 27A, 20-30A MPPT would be fine.

800W/14V = 57A, 50-60A MPPT would be fine.

Yes, I know that 20/50A are under the minimum, you'll likely never lose much.
 
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