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L G avatar image
L G asked

Does Victron 150/70 prefer higher or lower voltage? Implications on panels in series or parallel.

Hi - I have 4 x 365 watt panels that have rated MPP specs of 39V and 9.3A. I have a victron 150/70TR. The panels will be combined in a midnight solar combiner box at the array and travel via 2/0 Al (buried wire) 160 feet to my charge controller. Was planning on paralleling the panels as 39V loss on 2/0 Al should not cause a significant voltage drop. Or should I series 2, series 2, and parallel those two strings to send 78V to the CC. It's charging a 24V battery (2x12V UT1300 Lionenergy batts in series).


MPPT Controllers
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2 Answers
wkirby avatar image
wkirby answered ·

Definately go 2 series, 2 parallel.
The benefits are less Voltage drop over your transmission cable but also higher Voltage to start the charge controller earlier in the morninbg and keep it going later in the evening.

I also have 24V system and I tried a 37V PV setup. On a dull day there wasn't a high enough headroom Voltage to make any significant power. It only really worked in full sunshine.

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L G avatar image L G commented ·

Excellent. Will do Wkirby!

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Elimac avatar image
Elimac answered ·

I also have a 150/70 in a 24V system. I started with 2 strings of 3 panels in series and now have 3x 3. I agree with Wkirby, go for 2x2. It would be nice if you could get 2 additional panels and make 2x 3. That would match pretty well your mppt.

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L G avatar image L G commented ·

Thank you! Great input Elimac.

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