Guys,
I ran into the situation that the Model S 100D I got as a donor, have 3 different gauges 1/0 for the R-SDU, 2/0 for the HVJB in the front and 3/0 for the charger. Since most level 2 chargers only output 50 amps and I'm not planning to use superchargers, I was wondering if I can downgrade to awg # 8 that will hold good up to 55 amps. What you guys think?
Gen 3 Charger Cables gauge too BIG?
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ardillolambo
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alexbeatle
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Re: Gen 3 Charger Cables gauge too BIG?
Which year the car is from? As far as I've seen even North American Teslas have their cables marked in mm2.
Are you referring to the cable from the inlet to the on-board charging unit?
Are you referring to the cable from the inlet to the on-board charging unit?
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ardillolambo
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Re: Gen 3 Charger Cables gauge too BIG?
is a 2017 model S...and yes is the cables from the charging port to the charger. if using a level 2 charger that provides 50 amps a # 8 cable should be good. That's why I think is too big
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alexbeatle
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Re: Gen 3 Charger Cables gauge too BIG?
This would be my approach.
To select the conductor size assuming - For US, AC current, 50A max. continuous current in a cable of no more than 3 current carrying conductors (ground is not a current carrying) and with ambient temp of no more than 30C.
Multiply your max current by 125% factor. Then use the NFPA70 table 310.16 based on your wire type (TW, THHN, etc.) - what max temp wires're designed for 60C, 75C, 90C etc. I go with 60C for the wire type not listed - max derating.
Given the above min wire size would be 6awg.
If the ambient temp is above 30C need to use NFPA70 310.15(b).(1).(1) table to de-rate cable capability which will increase the wire size. Ex. if your ambient temp is 40C I'd go to 4awg.
Can access NFPA70 for free here...https://www.nfpa.org/codes-and-standard ... lopment/70
To select the conductor size assuming - For US, AC current, 50A max. continuous current in a cable of no more than 3 current carrying conductors (ground is not a current carrying) and with ambient temp of no more than 30C.
Multiply your max current by 125% factor. Then use the NFPA70 table 310.16 based on your wire type (TW, THHN, etc.) - what max temp wires're designed for 60C, 75C, 90C etc. I go with 60C for the wire type not listed - max derating.
Given the above min wire size would be 6awg.
If the ambient temp is above 30C need to use NFPA70 310.15(b).(1).(1) table to de-rate cable capability which will increase the wire size. Ex. if your ambient temp is 40C I'd go to 4awg.
Can access NFPA70 for free here...https://www.nfpa.org/codes-and-standard ... lopment/70