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Topic: Wire Size Wire? 2nd Ground For Smart Solar Charge Controller (Read 217 times) previous topic - next topic

Wire Size Wire? 2nd Ground For Smart Solar Charge Controller

My new Victron Smart Solar MTTP charge controller arrived today and it has connections just like my Renogy MTTP charge controller that supposedly isn't suitable for lithium batteries BUT it requires an additional ground wire.
What size wire is suitable for a chassis ground?
1993 U225 Build #: 4285
500 Watts Solar
Honda CRV AWD
Former 1981 Foretravel Travco
Retired, Full Time Off Grid Snowbird

Re: Wire Size Wire? 2nd Ground For Smart Solar Charge Controller

Reply #1 –
Probably 10 gauge but check with Victron to make sure

P
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Wire Size Wire? 2nd Ground For Smart Solar Charge Controller

Reply #2 –
Thanks Pierce. The manual doesn't say, and getting in touch with a live Victron person late this afternoon was impossible. 
I had to unload a closet, pull up the carpet and the closet floor in order to run a new wire.
I also see that the battery wire terminals on this Victron are smaller than those on my Renogy. At first glance it looks like I'll be trying to fit a baseball bat into a straw. , 
1993 U225 Build #: 4285
500 Watts Solar
Honda CRV AWD
Former 1981 Foretravel Travco
Retired, Full Time Off Grid Snowbird

Re: Wire Size Wire? 2nd Ground For Smart Solar Charge Controller

Reply #3 –
From an electrical perspective, you can never go wrong erring on the side of a larger gauge ground wire.
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Wire Size Wire? 2nd Ground For Smart Solar Charge Controller

Reply #4 –
Will Prowse of YouTube fame recommend using a swedge on the connections. Victron has a recommendation on the wire "count" for the stranded wire. Better clamping on wires with finer strands rather than a few course strands. I learned about the swedges a bit late for my connections.
1998 36 foot U270 Build No. 5328 WTFE, 900 watts solar, Victron controller, B2B, bat monitor, 600 AMPH lithium with 2018 Chevy Colorado toad, SKP #110239, Motorcade #17781, 2021 Escape 17B for when Coach is broken down and campsites are too small, retired and full-timer since Dec. 2020. Part of RV family since 1963.
 

Re: Wire Size Wire? 2nd Ground For Smart Solar Charge Controller

Reply #5 –
Quote from: Dakota Slim –
Thanks Pierce. The manual doesn't say, and getting in touch with a live Victron person late this afternoon was impossible. 
I had to unload a closet, pull up the carpet and the closet floor in order to run a new wire.
I also see that the battery wire terminals on this Victron are smaller than those on my Renogy. At first glance it looks like I'll be trying to fit a baseball bat into a straw. ,
Yes, I never was able to figure out why Victron used such small terminals without the possibility of using larger. And they don't fit a fan either. But they seem to work well and they fit into small spaces. I've often though about using an adapter to reduce the size of a larger wire down so it would fit.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)