Parallel 1/0 awg or 0 awg to max the amperage

Archetype-IS

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I want to see if I could combine (2) 1/0 awg wires in parallel and not using 4/0 wires. The reason is I have plenty of 1/0 awg copper wires and want to avoid buying 4/0 awg wires. I plan to use it in the 24v system with the EVE 280 batteries.

I see the 1/0 awg could handle it if you look at the conductor cross sections 53.5x2 is 107mm2 and 1 0000 (4/0) is 107mm2. I haven't been able to locate a combine calculator goes beyond 1AWG.

It is recommended to do so or spend the money on the 4/0 awg?

Below is the chart for some references.

WG gaugeConductor
Diameter Inches
Conductor
Diameter mm
Conductor cross section in mm2Ohms per 1000 ft.Ohms per kmMaximum amps for chassis wiringMaximum amps for
power transmission
Maximum frequency for
100% skin depth for solid conductor copper
Breaking force Soft Annealed Cu 37000 PSI
00000.4611.6841070.0490.16072380302125 Hz6120 lbs
0000.409610.4038484.90.06180.202704328239160 Hz4860 lbs
000.36489.2659267.40.07790.255512283190200 Hz3860 lbs
00.32498.2524653.50.09830.322424245150250 Hz3060 lbs

Thanks.
 
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time2roll

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How many amps do you plan to pull out of the 24v 280Ah battery? How long is the wire?
I am thinking a single 1/0 should be fine.
 

Archetype-IS

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How many amps do you plan to pull out of the 24v 280Ah battery? How long is the wire?
Plan to use
Plan to max 167amp for a 24v @ 4000w system. (maybe max 200amp?) The manual recommend 4/0 awg wires for the DC battery bank and over current device protections. Also plan to use two BMSs for two 24v 8 cells banks (2P8S). I only have one BMS 24v 100amp so far due to the shortage. So, I plan to have one BMS up for a short term..

Wire length, maybe under 24 inches...but will keep it as short as possible.

Magnum MS-4024PAE specs:

1620005660380.png

1620005609722.png
 

time2roll

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Yea I would wire with single 1/0 and not worry one wit. Possibly 1/0 from each battery if the inverter connector can take both lugs. I see no need to go 4/0 here.

Forget that NEC current unless you plan to run max power continuous for 3+ hours. That is just compliance with the 125% rule for continuous service circuits. I doubt that applies for your usage.
 

MasterSparky66

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Just know if you run parallel conductors make sure they are the same length. If they are different lengths they will have different resistance and more current will flow on the one with less resistance.
 

Alphacarina

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Yea I would wire with single 1/0 and not worry one wit. Possibly 1/0 from each battery if the inverter connector can take both lugs. I see no need to go 4/0 here.

Forget that NEC current unless you plan to run max power continuous for 3+ hours. That is just compliance with the 125% rule for continuous service circuits. I doubt that applies for your usage.
I agree. Lots depends on what you're going to run with the inverter. Typically, inverters are seldom ever run at max capacity for very long - The battery bank just wouldn't put up with it. If you're thinking a maximum of 167 amps, then the 1/0 wire is more than adequate. None of your tables mention cable lengths either - While you *might* actually need a 4/0 cable if the inverter was to be operated at 5Kw for an extended period, with cables 20 or 40 or 60 feet long, for 167 amps with a 2 foot cable, your 1/0 wire will never get warm

Don
 

RayfromTX

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The temperature rating of the wire is also very important. There is a big difference between 60c, 75c, 90c and 105c wire. Now would I rely on the 105c rating for long periods of time and accept that I was running the wires hot but they could take it? No, but I would certainly use my 105c wire ratings to figure breaker and fuse sizes and to allow for short surges as long as I also considered the implications of multiple conductors in conduit, length of conductor runs and ambient temperature ranges that the wire might experience. My 8000 watt inverter calls for 2awg coming from the battery. I am using 1/0. Many here would recommend 4/0. Knowledge and judgement make the decision for me. If I lacked those I would play it safe and upsize the wire.

Parallel wires have some funny rules in the codes. If I recall correctly one of those rules is that feeder wires can't be paralleled if below 1awg. I would look that up before relying on my aged mind but I think that is correct. I've never been able to explain why that would be.
 

rcrracer

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The temperature rating of the wire is also very important. There is a big difference between 60c, 75c, 90c and 105c wire. Now would I rely on the 105c rating for long periods of time and accept that I was running the wires hot but they could take it? No, but I would certainly use my 105c wire ratings to figure breaker and fuse sizes and to allow for short surges as long as I also considered the implications of multiple conductors in conduit, length of conductor runs and ambient temperature ranges that the wire might experience. My 8000 watt inverter calls for 2awg coming from the battery. I am using 1/0. Many here would recommend 4/0. Knowledge and judgement make the decision for me. If I lacked those I would play it safe and upsize the wire.

Parallel wires have some funny rules in the codes. If I recall correctly one of those rules is that feeder wires can't be paralleled if below 1awg. I would look that up before relying on my aged mind but I think that is correct. I've never been able to explain why that would be.
1/0 everywhere

NEC requirement is 1/0 minimum can be paralleled. It doesn't matter if it is a feeder or a branch circuit, hence everywhere.
 
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MichaelK

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One alternative way that would be doable is to cut three or so parallel lengths of the 1 gauge, coil them around each other, and then terminate them with a single crimped 3/0 or 4/0 lug. Just make sure the the ends contact each other inimately. What I would do is uncoil the last 2-3" of wire, line up the three strands, then re-coil them together before crimping the single lug.
 

MattiFin

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Parallel wires have some funny rules in the codes. If I recall correctly one of those rules is that feeder wires can't be paralleled if below 1awg. I would look that up before relying on my aged mind but I think that is correct. I've never been able to explain why that would be.
parallel wires would need invidual fuses for same degree of protection as one thick wire, otherwise you overload one of the wires in some obscure faults.

thicker than 1 AWG is some sort compromise to what is physically possible to manhandle. flexible connection to 3000A supply would otherwise require very stubborn cable!
 
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