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Is my set up safe?

You should have the disconnect between the panels and the solar charge controller.
You don't need one on the system side of the solar charge controller.
You don't need them in front of the inverters.
I assume you can turn them off
you should put a disconnect between the positive busbar and the battery.
Oh and a 300 mrbf fuse on each battery postive terminal.
 
smoothJoey said:
You should have the disconnect between the panels and the solar charge controller.
You don't need them in front of the inverters.
I assume you can turn them off
you should put a disconnect between the positive busbar and the battery.
Click to expand...
Joey...that really is much appreciated. (y)
 
Actually if those wires between battery positive and the busbar are short enough that they can't dead short to a negative terminal then you don't need fuses there.
 
Still no wire gauges and you should have a means of disconnect between the panels and the solar charge controller.
 
Gonna be hard to find a disconnect switch that is rated over 350 amps.
Probably should put in 2 one for each battery positive.
And if you are doing that you should put mrbf fuses on the terminals.
 
smoothJoey said:
Still no wire gauges and you should have a means of disconnect between the panels and the solar charge controller.
Click to expand...
He has one (I think), look near the bottom right corner of the SCC, I believe taht is a double pole breaker.
 
Actually @Solarfun4jim why not go 24 volts?
Make those cells into an 8s battery.
Half the amperage of the system.
Half the size of the wires.
The switching gear will be able to handle the load with relative ease.
Get per cell balancing.
 
smoothJoey said:
Actually @Solarfun4jim why not go 24 volts?
Make those cells into an 8s battery.
Half the amperage of the system.
Half the size of the wires.
The switching gear will be able to handle the load with relative ease.
Get per cell balancing.
Click to expand...
I concur, 24v makes a lot more sense, especially considering that you don't seem to have any DC loads (one of the main reasons people often stick to 12v).
I see many upsides and no downsides in this situation
Your charge controller will be a lot cheaper too.
 
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Guys you are right again. My original thinking was utilising some 12v equipment, but that has been negated now. My BMS has 8 attachment wires anyways.... so yes, it does make more sense....will recost the SCC and inv/charger now. Fortunately i have still to purchase these. Cells and BMS i have now got. Solar panels on the way....everything else just to be sourced now.
Only addition i might add later is a sterling b2b but that is fine also with a 12v - 24v unit....so no probems.
 
Solarfun4jim said:
Guys you are right again. My original thinking was utilising some 12v equipment, but that has been negated now. My BMS has 8 attachment wires anyways.... so yes, it does make more sense....will recost the SCC and inv/charger now. Fortunately i have still to purchase these. Cells and BMS i have now got. Solar panels on the way....everything else just to be sourced now.
Click to expand...
Inverter/Charger will be the same price, but you can now either get an SCC half the size (and hopefully half the cost) or a PV array twice the size.
 
I don't think you need the disconnect anymore since you can turn the inverter/charger off and you have panel side disconnect to turn off the solar charge controller.
You could even go with a 2 position mrbf terminal fuse and get rid of the positive busbar if you wanted.
 
Can you find a 250A breaker from a reputable brand for a price you can stomach? Most reputable brands don't produce breakers above 200A, many chinese off brands claim higher ratings but people say they are not reliable (which for a circuit breaker is a big deal). Outback, Xantrex and Midnite solar all make panel mount 250A breakers but they cost roughly $100. Waytek Wire--which is a reputable (US) seller--has one or two options that might be more affordable, but I don't know anything about the brands.
 
Dzl said:
Can you find a 250A breaker from a reputable brand for a price you can stomach? Most reputable brands don't produce breakers above 200A, many chinese off brands claim higher ratings but people say they are not reliable (which for a circuit breaker is a big deal). Outback, Xantrex and Midnite solar all make panel mount 250A breakers but they cost roughly $100. Waytek Wire--which is a reputable (US) seller--has one or two options that might be more affordable, but I don't know anything about the brands.
Click to expand...
Hi Dzl,
im not sure of the quality of the 250A unit i sourced, but it had reasonable review ratings, but of course that dont go for much.

This is what i was thinking of using....

Car Audio Circuit Breaker DC12V-42V Manual Reset Car Stereo Audio Inline Circuit Breaker (250A) : Amazon.co.uk: Business, Industry & Science

Car Audio Circuit Breaker DC12V-42V Manual Reset Car Stereo Audio Inline Circuit Breaker (250A) : Amazon.co.uk: Business, Industry & Science
www.amazon.co.uk
 
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Personally, I don't have experience with that breaker, but I would avoid it, it looks like one of the many off brands copying Bussmann breakers. If the reputable brands can't or don't make a breaker above 150-200A in that form factor and at that price point, I suspect the clones can't be doing what the top brands can't or don't for less money. Breakers are one place where I think it pays to stick to reputable brands that are trusted by the industry.
 
Dzl said:
Personally, I don't have experience with that breaker, but I would avoid it, it looks like one of the many off brands copying Bussmann breakers. If the reputable brands can't or don't make a breaker above 150-200A in that form factor and at that price point, I suspect the clones can't be doing what the top brands can't or don't for less money. Breakers are one place where I think it pays to stick to reputable brands that are trusted by the industry.
Click to expand...
So better a 'megafuse' then and simply carry a spare.
 
Solarfun4jim said:
So better a 'megafuse' then and simply carry a spare.
Click to expand...
A reluctant yes, would be my opinion, unless you want to shell out the money for a quality 250A+ breaker from a reputable company or could possibly get away with a 200A breaker which would be cheaper and more readily available.
 
I ended up using a Class "T" 200 amp fuse on my inverter feed from my battery bank to the inverter. The fuse holder and fuse will set you back at least $60, and a replacement fuse is $25 or so. But it sure is cheaper than fire damage.

My individual battery strings are on 125 amp MBRF fuses. They should handle it, but they are a bit close, with just a 58 volt rating. Full charge could hit 58.8 volts, but I have it set to stop at 57.6 volts. On a lower voltage system, MBRF fuses should be fine, but if your battery bank can supply more than 5,000 amps of short circuit current, they still might sustain an arc inside. On a 48 volt system, they are only rated to interrupt 2,000 amps. If my system suffers a dead short, they may arc over, and the Class T will be the safety valve.
 
smoothJoey said:
Why are you so keen on mega fuses?
Click to expand...
Thanks Joey, I'm not particularly keen on Megafuses, but open to your suggestions. The inverter output can peak at 6000W (for a few seconds) and with the 24V setup, im estimating that it could draw 250A. I would prefer something that could be 'reset' rather than replaced if blown. I really dont expect my loads to test the full inverter capacity, but there is always the one circumstance that blows the fuse when you are in your RV, miles from anywhere...lol.
Would it be worthwhile adding a cheap 300A megafuse inline, so that if the breaker didnt trip, the fuse would blow (as a belt and braces senario....cheaper than $120 for a 'quality breaker') ???
Im assuming of course that the circuit breaker would trip long before the fuse would blow? (fuse only for back up)
 
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