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2000w inverter with long wire, will it work (safely)?

Thanks, @eXodus, in real world there are many factors affecting the result, like the quality of wires (pure copper?) I will definitely run a stress test before I put anything that does 150a-200a in my trailer. I'd run a 1500w load for 10 minutes, if it gets uncomfortably warm, I will upsize.
Good precaution.
I don't like anything above 100a. So I had the choice - 24V system - or reducing consumption.

I went out and got a 700W Coffee maker ($20) and 600W Microwave ($60)- issue solved. Hardly see more then 60A
 
Good precaution.
I don't like anything above 100a. So I had the choice - 24V system - or reducing consumption.

I went out and got a 700W Coffee maker ($20) and 600W Microwave ($60)- issue solved. Hardly see more then 60A
BTW, what BMS do you use for your 280ah cells? I am also wondering if these cells can comfortably handle 1C discharge?
 
BTW, what BMS do you use for your 280ah cells? I am also wondering if these cells can comfortably handle 1C discharge?
you must mistaken me - I don't have 280ah cells. I bought my batteries done - no idea what BMS.

I got a 1200W Inverter - and when I had a 1000w coffeemaker and my 80W fridge kicked in - it tripped into overload.
With the 700-750w coffeemaker - no problem.

Just don't see the point investing into a massive battery bank and wiring, instead of just buying a cheaper appliance :p
 
why would ~5% voltage drop makes inverter generate excessive heat in a vicious loop? This makes no sense. Inverters have their operational voltage range, outside of that, they shutdown. inside of that range, it makes not difference if the 12v was from battery(zero drop) or was from 12.5v dropped to 12v.
Watts are watts and as volts drop, amps increase.

If you don't believe low supply voltage will increase heat, I can't help you.
 
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Watts are watts and as volts drop, amps increase.

If you don't believe low supply voltage will increase heat, I can't help you.

a 5% increase in amps won’t make that much difference.
 
a 5% increase in amps won’t make that much difference.

Power dissipation in wires, fuses, transistors goes as the square of current, so 5% increase in current (e.g. due to 5% decrease in voltage) will increase power dissipation in inverter MOSFETs by 10.3%. Precise amount of heating will depend on what thermodynamics of air flow says, but expect about 10.3% increase in temperature rise, 10.3% decrease in maximum power handling of inverter.
 
Power dissipation in wires, fuses, transistors goes as the square of current, so 5% increase in current (e.g. due to 5% decrease in voltage) will increase power dissipation in inverter MOSFETs by 10.3%. Precise amount of heating will depend on what thermodynamics of air flow says, but expect about 10.3% increase in temperature rise, 10.3% decrease in maximum power handling of inverter.
Thank you. One more source of heating is the wire itself and heat transfer thru the terminals.

My opinion on decreased inverter lifespan is always about low input voltage causing excessive heating of the inverter.
 
Power dissipation in wires, fuses, transistors goes as the square of current, so 5% increase in current (e.g. due to 5% decrease in voltage) will increase power dissipation in inverter MOSFETs by 10.3%. Precise amount of heating will depend on what thermodynamics of air flow says, but expect about 10.3% increase in temperature rise, 10.3% decrease in maximum power handling of inverter.
Thanks, my point is that the inverter will operate @ 10.5v+, per spec. obviously not optimally, but the condition is rare - I’d have to use a hair dryer at max heat setting, when battery soc is low, in such condition I want my setup to be safe. Not running optimally. In almost all other cases, it pulls 200-500w, 10-30a, 1-2awg wire should work very well.
 
You can imagine what surge current of 5x motor running current does. Even if within inverter surge rating 2x its continuous rating, that is 4x the dissipation in MOSFETs and 4x the temperature rise theta J-C (junction to case). Heatsink won't have time to rise in temperature, but might have started out hot from recent full-load operation. Like running a tool that is switched off, then back on before heatsink has cooled.

Normal operation might be 25 degree C ambient, 65 degree heatsink, 125 degree junction (for a power transistor rated 150 degree max junction.) Theta J-C being 60 degrees at full load. Double current for a couple seconds would make that 240 degree rise, 305 degree junction. Shouldn't do that, for a well-designed inverter I would expect junction temperature under rated surge conditions to remain within absolute max, 150 degree C. I've seen 175 degree for some parts. But off-brands, I wouldn't be surprised if they simply tested surge current and declared it good without considering what junction temperatures occur.

Resistive heating loads aren't such an issue, no surge current due to TCR of typical heaters. Tungsten filament incandescent bulbs, surge is about 10x operating current.
 
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I am fairly sure 2awg will not generate excessive heat to start a fire, this is based on what 2awg copper wire is rated for, and my 1st hand experience of running 800w continuous on 4awg wire (+2c after 5minutes).
You are wrong. That is not safe. Sorry.

What fuse did you use? None, right?

Listen to what these folks are telling you. Some are EEs and such. Electrical fires are bad.
 
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I want to give an update on this. as I promised when I started this thread.

First I did make a mistake, I thought 2 4awg wires = 1 2awg wire. I probably got this wrong idea from nail gauges, for which the width is what matters, but for wires, it's the area and 2 4awg wires are equivalent to a single 1awg wire. (My renogy inverter comes with 3 feet cable which is made of 2 4awg wires in parallel)

As I was building the battery, I also found a space in my trailer, under the microwave cabinet, that would fit my 2000w inverter, this cuts the distance I need to run wires by more than half and I was able to avoid some very sharp turns. so I ended up using both 2/0 awg and 1awg (not 1/0) wires between battery cell and inverter (~1 foot 1awg, ~5 feet 2/0).

I tested the setup at ~180A for over 15minutes(A 13500BTU A/C, and a hair dryer with heating turned off), with a temp gun scanning varies components between cell and inverter.

Almost everything remained cold (< 2 degree higher), with the exception of a 250A manual reset breaker, which got fairly hot. Later I read these kinds of breakers are supposed to get hot to do there job(thermal breaker)


I hope this will help other people in similar situation.

Also thanks to all the folks responded to this post with fact, data instead of strong opinions.
 
Later I read these kinds of breakers are supposed to get hot to do there job(thermal breaker)

They work by thermally acting.
They SHOULD NOT GET HOT.
What brand are you talking?

Then again how hot was hot?
Maybe a better breaker is in order?
 
One of the design principles is that the inverter and batteries are close together.

Can you post your floor plan. I have been able to relocate batteries from the tongue of 12ft pop-up, a 14ft TT, and my current 17ft TT.

I believe you can do it too.
 
You have to make sure you don’t reduce tongue weight. That is an important safety feature on trailers.
Agree.
With my three different towables, I have never used any WDH or sway controls. Just drop the tongue on the ball. Is there any other safety issue?
 
You have to make sure you don’t reduce tongue weight. That is an important safety feature on trailers.
+1 on this. I could have move the battery to post axle, so it can be placed right next to inverter. but that changes weight distribution and I don't want that.
 
They work by thermally acting.
They SHOULD NOT GET HOT.
What brand are you talking?

Then again how hot was hot?
Maybe a better breaker is in order?
it's significantly warmer, You can still touch it, I think it was about 50-60c
 
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