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Please critique my electrical diagram (12v | 3.6-4.8kw bank | 2kw inverter | DC-DC charging)

rboothe

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Nov 10, 2020
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Hey all! I learned a lot since my first proposed Electrical Diagram. If anyone could take a look at my second version, which is quite different, I'd be beyond grateful.

This is a 12V system with 3.6-4.8kw battery bank (300-400aH), 2000 watt inverter, DC-DC alternator charging, and 620 watts of solar.

A few questions I have regarding the diagram:
  1. Is the battery bank fuse size both in the positive bus bar and near the bank adequately sized? Will the 300A Master disconnect switch be adequate as well?
  2. I have a TON of DC load fuses (I've listed all of the potential AC/DC loads in the diagram.) I'm guessing I can wire some of the DC loads together so that they are not individually fused but is that correct?
  3. Will the way I want to connect the battery bank Anderson connectors work?
  4. Would you add an additional resettable fuses for the AC breaker box? Or additional resettable fuses anywhere else so I don't waste the ANL + busbar ones? (ANLs could potentially be backups.)
THANK YOU!!! I've learned so much from this group. Thank you for your time.
 

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  • Electrical diagram V2_pic.JPG
    Electrical diagram V2_pic.JPG
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Looka like a nice drawing but I can't make out any detail.
 
This forum downsizes attachments to the point that it is hard to read schematics. If you upload to imgur.com or some other third party website and then link to that, it will be easier to make out the details.
 
@rbooth its still to small for my lousy eyesight.
But what I can see looks good.
Why do you have a dedicated dc fuse block and a combined ac/dc load center?
 
@rbooth its still to small for my lousy eyesight.
But what I can see looks good.
Why do you have a dedicated dc fuse block and a combined ac/dc load center?
In my design I have many different DC loads, all individually fused, which are not series connected together. For example, Bedroom reading light/USB #1 had a separate fuse from Bedroom reading light/USB #2. I have (24) individual DC loads and the AC-DC distribution box only holds (15). All the individual DC loads are listed on the schematic but I realize it's super small, so let me just post them below:

DC Load Fuses:
  • Bedroom puck lights
  • Living room puck lights
  • Under cabinet LED strips
  • Garage LED strips
  • MaxxAir Fan #1 High
  • MaxxAir Fan #2 Low
  • 12V Fridge
  • Water pump
  • Composting toilet fan
  • Motorized ball valve or solenoid on grey water tank
  • 12V charging station
  • 12V charging station #2
  • Bedroom reading light/USB #1
  • Bedroom reading light/USB #2
  • Twinkle lights bedroom
  • Lights on outside of van
  • Battery bank warming pad and indoor freshwater tank warming pad
  • Outdoor grey water tank warming pad
  • Shower puck light?
  • Actuators on bed?
  • Reading desk light #1?
  • Reading desk light #2?
  • Cameras?
  • 12V TV?
However, I think I'm just going to combine loads so I only have to use the AC-DC distribution panel. Do you have a recommendation on combining DC loads into one fuse? I'm not sure how folks choose to combine certain loads together...

Thanks!
 
In my design I have many different DC loads, all individually fused, which are not series connected together. For example, Bedroom reading light/USB #1 had a separate fuse from Bedroom reading light/USB #2. I have (24) individual DC loads and the AC-DC distribution box only holds (15). All the individual DC loads are listed on the schematic but I realize it's super small, so let me just post them below:

DC Load Fuses:
  • Bedroom puck lights
  • Living room puck lights
  • Under cabinet LED strips
  • Garage LED strips
  • MaxxAir Fan #1 High
  • MaxxAir Fan #2 Low
  • 12V Fridge
  • Water pump
  • Composting toilet fan
  • Motorized ball valve or solenoid on grey water tank
  • 12V charging station
  • 12V charging station #2
  • Bedroom reading light/USB #1
  • Bedroom reading light/USB #2
  • Twinkle lights bedroom
  • Lights on outside of van
  • Battery bank warming pad and indoor freshwater tank warming pad
  • Outdoor grey water tank warming pad
  • Shower puck light?
  • Actuators on bed?
  • Reading desk light #1?
  • Reading desk light #2?
  • Cameras?
  • 12V TV?
However, I think I'm just going to combine loads so I only have to use the AC-DC distribution panel. Do you have a recommendation on combining DC loads into one fuse? I'm not sure how folks choose to combine certain loads together...

Thanks!
I don't think its bad to have the second fuse block if you need it.
Depending on the max ampacity of the branch circuits of the ac/dc combo, maybe you could use the fuse_block as a remote sub panel.
My guess is there will be cluster of low amperage stuff that is logically or physically related that could all go on the sub_panel.

I think you have a good handle on the design.
 
I don't think its bad to have the second fuse block if you need it.
Depending on the max ampacity of the branch circuits of the ac/dc combo, maybe you could use the fuse_block as a remote sub panel.
My guess is there will be cluster of low amperage stuff that is logically or physically related that could all go on the sub_panel.

I think you have a good handle on the design.
That seems like a more elegant solution. In lieu of doing that, what are OP’s other options?
 
I don't think its bad to have the second fuse block if you need it.
Depending on the max ampacity of the branch circuits of the ac/dc combo, maybe you could use the fuse_block as a remote sub panel.
My guess is there will be cluster of low amperage stuff that is logically or physically related that could all go on the sub_panel.

I think you have a good handle on the design.
Thank you for taking a look. I like the idea of the remote sub panel. I might stick with the two fuse centers then. I think it gives me more options in the future too to potentially add on other DC items.

My other question is some folks were saying it's redundant to have an ANL fuse and a resettable fuse for the fuse block. Although I realize it is, I thought it might be better to have the resettable so I don't have to replace the ANL each time the DC block trips. However, I'm not sure how often that would even be. And the resettable might provide another point of failure. How do you feel about it?
 
That seems like a more elegant solution. In lieu of doing that, what are OP’s other options?
There is the one that he is chosen which is fine.
Everything is all in one place which is nice.
Some folks would do a bunch of logically related lights in parallel with a single fuse and switch.
 
Thank you for taking a look. I like the idea of the remote sub panel. I might stick with the two fuse centers then. I think it gives me more options in the future too to potentially add on other DC items.

My other question is some folks were saying it's redundant to have an ANL fuse and a resettable fuse for the fuse block. Although I realize it is, I thought it might be better to have the resettable so I don't have to replace the ANL each time the DC block trips. However, I'm not sure how often that would even be. And the resettable might provide another point of failure. How do you feel about it?
Its ok to have a quality breaker and a quality fuse.
Even better if the breaker is sized a bit smaller so it trips first.
That breaker should hopefully never trip though.
If it ever did you would not want to reset it until you know what the problem is.
One thing I tend to do is use a common wire size and fuse where possible, even if it means over sizing some wires.
That way you don't have to keep so many spare fuses.
 
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Its won't to have a quality breaker and a quality fuse.
Even better if the breaker is sized a bit smaller so it trips first.
That breaker should hopefully never trip though.
If it ever did you would not want to reset it until you know what the problem is.
One thing I tend to do is use a common wire size and fuse where possible, even if it means over sizing some wires.
That way you don't have to keep so many spare fuses.
Good idea. I'll try to do just that. Thanks again.
 
let me know if you find a 12v TV! usually they are all 120v with internal transformers unless you want to tear into one.
Theres some LED monitors that have external transformers that are 12-19V. I want to get a 12V 42" tv but may be stuck with going 120v, they are about 60-80watt draw.
 
let me know if you find a 12v TV! usually they are all 120v with internal transformers unless you want to tear into one.
Theres some LED monitors that have external transformers that are 12-19V. I want to get a 12V 42" tv but may be stuck with going 120v, they are about 60-80watt draw.
My last tv had a power brick.
Not sure if it was 12 volts but you could use a buck converter.
 
That's a lot of fuses. For bunching low voltage wires these are common in the RV industry..........



With the size of fuse and wire going to your second fuse block it's not likely to ever blow, I think the breaker is not required.
 
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That's a lot of fuses. For bunching low voltage wires these are common in the RV industry..........

Ah, thank you. I take it they're basically the same as the caps used in rewiring light fixtures in your house. I was thinking of using the Wago connectors for basically the same thing, but maybe a quicker, stronger connection https://www.ebay.com/itm/2338736124...-8MxJwvOvs7iW7E8Rp6AjbYEYQTMUTLAaAtSNEALw_wcB
 
I have hundreds of those closed end crimps and they work but the only crimper that seems to work decently on them for me is lineman pliers.
I like this part of the crimp connectors...

UL, CSA & RoHS compliant
The 221 series of connectors appear to be UL 486C listed.
 
Tried to edit my last post....
I do like WAGO's-no hesitation to use them....
The linked ones didn't appear to have any certifications.
 
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