schmism
Solar Addict
Our current codes rate wire current carrying capacity by.. wait for it.... insulation type. However still not saying #6 should be used to carry 300a
Silicone wire on your solar system setup
- Thread starter sirslayer
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timselectric
If I can do it, you can do it.
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Not exclusively.
Ratings are based on several factors.
Insulation type, plays a bigger role in voltage and location Ratings than amperage Ratings.
Location of the wire plays a larger role in the current carrying ability of the wire…
Free air #10 is rated for 100A… it is insane the size wire power companies feed houses with… but with zero conduit or surrounding structures in a line drop, the wire can dissipate the massive resistance heat in a large load.
So… the #6 likely CAN support 300A… but it better be in free air, not inside a building or enclosure of any kind…
Also, that 300A likely is a rating similar to power company feeder ratings… where “200A” means, derated for intended time of use case, etc…
I do hope the OP listens to our advice. Wasting money is never a good idea.
Size the CONDUCTOR for best continuous use loads… use the insulation for overload protection…
10W of waste… um… no…
#6 at 300A would be wasting far more than 10 watts…
Somebody please do the math.
Size the CONDUCTOR for best continuous use loads… use the insulation for overload protection…
10W of waste… um… no…
#6 at 300A would be wasting far more than 10 watts…
Somebody please do the math.
OzSolar
Whatever you did, that's what you planned.
Whatever you end up doing keep a close eye on it. but I agree with others that you shouldn't.
I'm not an EE but I would say anything over 5% VD is going to wreak havoc with your settings. IE: 10% for sure will. IE: You're charging at 300 Amps, one end of the wire is 14v and but other end will be 12.6.V
Voltage Drop x Amps = Watts = Heat
1.4V x 300A = 420 watts of heat your wire has to safely get rid of.
I'm not an EE but I would say anything over 5% VD is going to wreak havoc with your settings. IE: 10% for sure will. IE: You're charging at 300 Amps, one end of the wire is 14v and but other end will be 12.6.V
Voltage Drop x Amps = Watts = Heat
1.4V x 300A = 420 watts of heat your wire has to safely get rid of.
I have a video where I push well over 300 amps through 14awg Romex, it passed the current just fine until the insulation lit on fire.
Edit: Just watched that video (admittedly I didn't watch it earlier, the title told me all I really needed to know), and he says at the end that his wire can take a 100 amp pulse for a short time. He was referring specifically to heavy acceleration on an e-bike, not a constant current. Also, an e-bike gets really good ventilation compared to a stationary battery system, which would keep the wiring much cooler.
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Per foot...
I can see this thread getting moved to the "Up in smoke" subforum, eventually. Some people have to learn the hard way.
schmism
Solar Addict
Its why i pushed to have the subforum added. Its important to see how bad the failures actually are.
In all fairness the OP is replacing #8 with #6
OzSolar
Whatever you did, that's what you planned.
Right. I think we were posting at the same time so I wasn't responding to you or really anyone for that matter.
Rather I just was speaking in general terms about measuring the actual voltage drop across an entire system (not necessarily even this one) from the first connection through the OCP and switching to the last connection then doing some pretty easy math to see if the heat being generated sounded reasonable.
sirslayer
New Member
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Well after hearing the advice , that’s why I’ve posted this thread on your advice ( which is many) my plan. Is not to go over 200a and I went ahead and double cabled the 6 awg which reduced the heat. I may doubled cabled the 8 awg which is regular pvc cable to my solar panels because the heat I’m getting off the wire is to warm compared to the rest of the system. I thank you for your input and that’s what I wanted to hear .
sunshine_eggo
Happy Breffast!
When you double the conductors, each one needs a fuse/breaker.
Nobodybusiness
Collecting the leftovers of the Great Sky Reactor.
umm no 6 AWG is NOT rated for 300Amps power transmission. It could handle it For a microsecond maybe at a foot long.
12 volt X 200 AMP for 10 ft. The cable recommended AWG is 4/0 for a 2% Voltage Drop.
12 volt X 200 AMP for 5 ft. The cable recommended AWG is 3/0 for a 2% Voltage Drop.
Even at the 1000 watts you say it would be 80+ amps
That's 5 ft of 3 awg wire.
Voltage Drop Calculator | Southwire
www.southwire.com
Not sure how they haven't caught on fire yet.
Notice the reason this youtuber went to silicone is not to handle heat better, it is to increase the flexibility of the wire.
If you need flexibility, sure, use silicone insulated, sized well to still handle the energy flow without heating up.
But do not do it because it has more amperage capability… it doesn’t. It has a higher heat managing capability. Heat wastes watts.
Don’t waste watts.
And this guy still doesn't get it. The number of strands of wire means NOTHING.
DerpsyDoodler
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What is it you are not understanding?
Heat in the wire is caused by resistance to the flow of electrons (let's call it friction). Friction prevents the electrons from flowing freely and smoothly (like a well-lubed ball-bearing) because there is not enough space for all of the electrons needed for x amount of current (amps) to flow through.
Trying to cram those electrons through that pipe (regardless of what the pipe is wrapped in) will cause electron flow to be stifled and thus turned into heat. The insulation itself does not change the physical characteristics of the copper. It just handles the heat of the copper without it [the insulation] (itself) burning up.
Does this help?
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