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Old 04-02-2013, 11:08   #1
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Battery Draw

I have 4 Gel Cell 6v 180ah batteries making up a 360ah 12v house bank. I have a 2000w inverter I use to power 120v ac appliances. If I pull 70-80 amps from the microwave or toaster for 2-3 minutes straight will this damage the batteries in anyway?
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Old 04-02-2013, 12:01   #2
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Have u actually stopped tried and seen it pulls 70-80amps??that sounds awfully high
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Old 04-02-2013, 12:04   #3
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Re: Battery Draw

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I have 4 Gel Cell 6v 180ah batteries making up a 360ah 12v house bank. I have a 2000w inverter I use to power 120v ac appliances. If I pull 70-80 amps from the microwave or toaster for 2-3 minutes straight will this damage the batteries in anyway?
it's OK, that is what it is all for
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Old 04-02-2013, 12:06   #4
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Re: Battery Draw

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I have 4 Gel Cell 6v 180ah batteries making up a 360ah 12v house bank. I have a 2000w inverter I use to power 120v ac appliances. If I pull 70-80 amps from the microwave or toaster for 2-3 minutes straight will this damage the batteries in anyway?
For short durations the GEL's should have no trouble with that at all.
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Old 04-02-2013, 12:36   #5
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Re: Battery Draw

A microwave I understand... but wouldn't it be much more efficient energy-wise to toast bread over a butane/alcohol/propane stove burner... or just have cereal?
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Old 04-02-2013, 13:03   #6
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Re: Battery Draw

I've got a small microwave, and a 2kW inverter. This draws approximately 90A from my 1000Ah 12V battery bank. Most of the time I use the propane oven or stovetop, but occasionally the microwave comes in handy. Running it for 6 minutes consumes 9Ah -- not too bad, really. The effective battery capacity will be less at this high rate, I would guess perhaps 10 or 15% worse.

Your 360Ah bank should support occasional microwave use.
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Old 04-02-2013, 14:09   #7
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Re: Battery Draw

I appreciate all of your response..
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Old 04-02-2013, 23:07   #8
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Re: Battery Draw

3 minutes at 80 amps = 4 Ah.
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Old 05-02-2013, 04:33   #9
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Re: Battery Draw

I wasn't so concerned with the 3-4AH depletion, as the 70-80 amp draw for 2-3 minutes.
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Old 05-02-2013, 06:01   #10
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Re: Battery Draw

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I wasn't so concerned with the 3-4AH depletion, as the 70-80 amp draw for 2-3 minutes.
The only issue would be if the inverter were installed with undersized wiring, I believe you need something like 3/0.
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Old 05-02-2013, 06:39   #11
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Re: Battery Draw

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The only issue would be if the inverter were installed with undersized wiring, I believe you need something like 3/0.
Why 3/0?thats huge,, wouldnt 2/0 or something close be good or is there a guide for this? Amps vs run vs wire size?
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Old 05-02-2013, 07:27   #12
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Re: Battery Draw

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Why 3/0?thats huge,, wouldnt 2/0 or something close be good or is there a guide for this? Amps vs run vs wire size?
I used one of the online wire size calculators to come up with the 3/0.
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Old 05-02-2013, 08:31   #13
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Re: Battery Draw

I'm using 4/0 for the inverter now. I never use it to max output. Most I've seen on the LED readout is about 800W FWIW....
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Old 05-02-2013, 20:37   #14
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80 amps, 10 ft, number 3 wire gives 2.5% voltage drop
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Old 05-02-2013, 21:14   #15
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Re: Battery Draw

Wiring and fusing for the inverter should be sufficient to support the total capacity of the inverter. A 2000 watt inverter can draw upwards of 180-200A at full capacity.

Wiring should therefore be as short as possible. For runs up to 10 feet or so, I'd use a minimum of AWG 2/0 and a Class-T or ANL fuse located near the batteries.

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