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alaskannoob avatar image
alaskannoob asked

MPPT RS designed to purposefully limit DC battery cable size? Why?

mppt-rs.jpgJust measured the slot that allows DC cables into the MPPT RS 450/200 terminals, and it will only allow .6" diameter cables. I have 2/0 cable that has a finished outer diameter of exactly .6" but the heat shrink is a bit more than that. I'd like to connect 4 x 2/0 cables (two positives, two negatives) to lessen my voltage drop and for the interest of safety.

I'm considering shaving a portion of the slot as needed to fit the 2/0 cables in. But it seems the MPPT RS slot is designed to limit the DC battery cable size purposefully. Is there a reason why bigger cables are not desired on this MPPT?

mppt rs
mppt-rs.jpg (209.6 KiB)
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2 Answers
Alexandra avatar image
Alexandra answered ·

@AlaskanNoob

Weird.

We have installed a few. They take the 70mm² cable quite fine. We used 2x 70mm² cable for the longer runs.

Maybe the manufacturer of the cable you have purchased has slightly thicker than normal insulation?

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alaskannoob avatar image alaskannoob commented ·

That's quite possible. This is the wire I'm planning to use (four of them):


https://store.polarwire.com/arctic-ultraflex-2-0-blk/

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Michelle Konzack avatar image
Michelle Konzack answered ·

Also the heat shrinking tube can be a problem if chosen to big.


In my first attempt it made together with the glow inside my 70mm² around 4,5mm thicker which was not a good thing.

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