question

justame avatar image
justame asked

is Stacking 2 Victron Smart Solar MPPT TR 150/70 possible

I am showing 962 watts, 9.3 amps array supply and Victron MPPT tr 150V/70 amp controller maxed at the 70 amps and bouncing between 72 amps and back to 69 & 70. With these readings, it looks like the array could produce around 150 amps out of the 2490 Watts. 2 parallel banks of 3 in series.

My 6 Panels are Maxeon SPR-MAX3-415 Watts, 11.75 rated current A. with Up to 22.2% efficiency. sp_mst_112c_max3_blk_ac_ready_ds_en_ltr_545906 copy.pdf

Our Daughter's Solar System of 45 qty 365 watt / 50V, with 5 inverters. 2 Inverters are on outside wall next to us and 3 Inverters and battery banks are in garage. Note: their 45 Solar panels are on our Steel Structured RV Pad Cover.

Our 400 Sq ft motor home uses over 6 times more power than their 3500 sq ft home, that is built like an igloo! We just paid $385 out of their $456! electric bill! I installed a Service Meter in the RV supply to monitor usage and my wife monitors peak and off peak, etc.

I'm trying to max out what I can do with Solar on our rig to reduce our consumption, so they can see a return on their investment! I'm working with the OFF peak hours and On Peak times between 4 to 7, which makes it kinda tough for my ole 82 year old brain to handle!

I was a electronic trouble shooter with Ford Motor company in the 1970 through the 90's. I have electrical experience, and I built a commercial building back in the 80's, and did the electrical service. I've been working with Solar as a Novice since 2004. I also fabricated and built the Solar array's seasonal tilting system.

But am having trouble wrapping my mind around the integration of the 2400 watt system and my motorhome's computer controlled two Xantrex 2500 watt inverter system. Solar people don't want to help unless they sell a system.

With the above in mind, Could I add another 150 V 70 A controller and stack them somehow, so we could maybe get the max capability of the Array, up to 140 Amps? If so what would I need to do and how?


MPPT SmartSolar
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1 Answer
derrick thomas avatar image
derrick thomas answered ·

You can stack multiple mppt on the same battery bank, but each mppt must have it's own pv array. You cannot connect a single array to multiple mppt controllers, they will not function properly. You mention you have 2 parallel strings, so connect 1 string to each of 2 controllers and you will be fine.

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