Critique my design please

[Desertsparky]

Excuse the yellow pad picture but I didn't feel like learning a drawing app. I'm no artist haha.
The current plan us 1/0 welding wire for almost everything except the buck converter. I didn't put it in there but I will have some form of disconnect or breaker coming in from solar panels and battery.

 

[12VoltInstalls]

current plan us 1/0 welding wire

Welding cable. Welding wire is something different ?

a 2000W 24VDC inverter will be like 80A. I would be likely to fuse at 100A but still do the big cables. I would also not double up the fuses; put a 100A at the battery, cable to the busbar, cable to the inverter.
Wire a 12VDC Bluesea fusebox out of the converter and put an inline ATC fuse from the converter to the fuse/distribution box.
If the Buck converter draws 20A cable it and fuse it accordingly after the busbar.

 

[DIYrich]

Input Plus of the 24 to 12 volt converter goes to the plus bus. Separate output plus from the 24 to 12 converter goes to the 30 Amp fuse for the 12v fuse block.

For the victron orion tr 24/12, the input negative goes to the negative bus, and the output negative goes to the fuse block. Probably doesn't matter.

 

[Desertsparky]

Welding cable. Welding wire is something different ?

a 2000W 24VDC inverter will be like 80A. I would be likely to fuse at 100A but still do the big cables. I would also not double up the fuses; put a 100A at the battery, cable to the busbar, cable to the inverter.
Wire a 12VDC Bluesea fusebox out of the converter and put an inline ATC fuse from the converter to the fuse/distribution box.
If the Buck converter draws 20A cable it and fuse it accordingly after the busbar.

I guess I didn't catch the brain fart on my drawing. The intention is for 30 amp inline going from bus bar to input on 24v side of the 24/12v transformer. The bluesea is exactly what I have for the 12v side. I've seen 20-40 converters. I was going to aim for the 40 because the bluesea is rated for 50

 

[MichaelK]

Before specing the components, I'd say first a bit more information about your goals here? What do you want to accomplish? Is this backup for power outages? What needs to be powered? One hundred amphours is rather low, even at 24V. That will be enough to keep the refrigerator running overnight, but will that be enough? We would rather not hear about how you were sitting there in the dark after the batteries went completely dead.

 

[Desertsparky]

Before specing the components, I'd say first a bit more information about your goals here? What do you want to accomplish? Is this backup for power outages? What needs to be powered? One hundred amphours is rather low, even at 24V. That will be enough to keep the refrigerator running overnight, but will that be enough? We would rather not hear about how you were sitting there in the dark after the batteries went completely dead.

This is for our skoolie conversion. It is a motor home situation not a full time living. It is mostly for fridge. I have an epever mppt (40 amp), 2x 100amp 12v litime batteries. I built one of will's crate systems and tried to run a freezer of of it with 500w solar. It was a rush build and never worked. Charges cell phones and runs a fan just fine haha. We never did buy a fridge etc for the bus so we went with a cooler. I have a total of 4 250w panels I can install once I get the 2000w inverter in and running properly. We would like the option of induction cook top but that's not likely to be a common use. I will eventually put an isolated dc to dc charger for while we are driving. Bus has a generator that runs the mini-split if needed. Ill also had a charger for the batteries for that some time down the road if needed.

 

[MichaelK]

OK, that is informative. I'll assume that the panels will be mounted flat on the roof? If that is the case, I'd say it's appropriate to de-rate the panel output to 60% to compensate for a less then optimal solar angle. What that means in the real-world is that 500W of panels for system 1 is really only 300W, and the four 250W panels will only be 600W.

Assuming you are using the skoolie for summer vacations, and that time of the year you're getting about 5 sunhours per day, then the 600W is likely to make you ~3000Wh (3kWh) of power per day. That should be enough for lights, TV, and the frig/freezer. I don't think the electric cooktop is going to be a realist option? Do you know what it's actual amp draw is? I don't have any personal experience with induction cooking.

Is there space on the rooftop for more than four of the 250s? With de-rating to 60%, you could add two additional panels, and upgrade to six while staying within your 40A limit. No-one complains they have too many panels!

 

[Desertsparky]

OK, that is informative. I'll assume that the panels will be mounted flat on the roof? If that is the case, I'd say it's appropriate to de-rate the panel output to 60% to compensate for a less then optimal solar angle. What that means in the real-world is that 500W of panels for system 1 is really only 300W, and the four 250W panels will only be 600W.

Assuming you are using the skoolie for summer vacations, and that time of the year you're getting about 5 sunhours per day, then the 600W is likely to make you ~3000Wh (3kWh) of power per day. That should be enough for lights, TV, and the frig/freezer. I don't think the electric cooktop is going to be a realist option? Do you know what it's actual amp draw is? I don't have any personal experience with induction cooking.

Is there space on the rooftop for more than four of the 250s? With de-rating to 60%, you could add two additional panels, and upgrade to six while staying within your 40A limit. No-one complains they have too many panels!

We have gone back and forth on cooking options so it's not a requirement. The generator we have for the mini split could very easily be used for cooking so it is not at all a stressor. Yeah mostly summer cross country trips. Although we do live in az so winter trips are more likely haha.