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Please help a newbie figure out if I have this setup right

PittsburghRed

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I would like some help to maker sure I have this setup worked out correctly.

Use Case: This is being built for fun and to see if a large renewable system could be used to provide a substantial upgrade to our energy needs. So really a test bed to learn the ropes.

My setup is shown below.

But a few specific questions:

1. My PV cables will be solar PV cable 10AWG, is this OK?
2. For battery and connections from controllers I was going to use 6AWG wire is this good or overkill?
3. Is the DC disconnect OK, I am confused some folks say a breaker and some say a disconnect switch?
4. Do I have the right size fuses between the SCC and the battery bank? I read it should match the SCC amperage so I went with 40A. And is the 175A between the bank and inverter the right size?
5. I think I have the turbine right but any suggestions? Not sure why you don't need a disconnect or breaker?

Any how thanks in advance.

my setup.JPG
 
But a few specific questions:

1. My PV cables will be solar PV cable 10AWG, is this OK?
Is there a reason not to make your panel configuration 4s?

2. For battery and connections from controllers I was going to use 6AWG wire is this good or overkill?
6 awg pure copper wire with 105c insulation is good for 100 fault amps which means 80 service amps.
Should be good for everything except the inverter and battery circuits.

3. Is the DC disconnect OK, I am confused some folks say a breaker and some say a disconnect switch?
For less than 3 strings on panels no over-current protection is required.
A double pole means of disconnect is a good idea though.
4. Do I have the right size fuses between the SCC and the battery bank?
Depends on the wire size.
6 awg pure copper with 105C insulation is rated for 100 fault amps which means you can go as big as 100 amps on the fuse.
I would use a 100 amp fuse.
The smallest fuse you could use is 50 amps.
40 amps / .8 fuse headroom = 50 amps.
And is the 175A between the bank and inverter the right size?
Depends on the wire size.
 
Suggest you redraw your diagram using positive and negative busbars.
It males the drawing easier to see and the implementation will be easier.
For bonus points use a fused positive busbar.
 
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Ok I am confused:rolleyes: But let me see if I can answer:

1. the reason I did 2S2P, is because the turbine is 24V, and therefore I had to make the battery bank 24V? so Therfore the 2S2P config gives me 24V for the PV array?

2. So what should the wire be for the batteries and the inverter if not 6AWG?

3. so swap the disconnect for a breaker? If yes what size?

4. so upgrade the 40A fuse between the SCC and the battery bank to 50A? I have a spare 175A would that be OK? or is that to big?

5. for the battery to inverter what size wire and fuse would you recommend? Again I was going to use 6AWG?

6. You lost me on bus bars! never mind fused bus bars. What are they and where would they go?

Thanks for the input though much appreciated.
 
I would like some help to maker sure I have this setup worked out correctly.

Use Case: This is being built for fun and to see if a large renewable system could be used to provide a substantial upgrade to our energy needs. So really a test bed to learn the ropes.

My setup is shown below.

But a few specific questions:

1. My PV cables will be solar PV cable 10AWG, is this OK?
That's fine.
2. For battery and connections from controllers I was going to use 6AWG wire is this good or overkill?
See response to Q 4.
3. Is the DC disconnect OK, I am confused some folks say a breaker and some say a disconnect switch?
Does it disconnect both the positive and negative side of the circuit? A breaker would trip if it detects over-current. A disconnect must he manually turned off. Either is fine. One provides a level of automated safety. If you've already purchased the switch, you can supplement with an inline fuse on each positive string (before the Y connector). They make MC4 connected inline fuses for solar arrays. Can be purchased off Amazon.
4. Do I have the right size fuses between the SCC and the battery bank?
You will want a 50A fuse. If your controller pushes the full 40A it could blow the fuse. (expected current + 25% is how this gets calculated). Your wire size should be able to support 50A between the controller and the battery (wire size and fuse size coincide, because the fuse is there to protect the wire).

I read it should match the SCC amperage so I went with 40A. And is the 175A between the bank and inverter the right size?
This is oversized. 1500W inverter / 24V = ~62A + 25% headroom = ~78A. You won't find a 78A fuse, so pick the next largest and size your wire to handle the fuse you pick.
5. I think I have the turbine right but any suggestions? Not sure why you don't need a disconnect or breaker?

Any how thanks in advance.

View attachment 92686

Your shunt wiring looks wrong. It must be between the battery negative and all other charges/loads.

This will get you started. Others may come along and notice stuff I missed or I'll be looking it over and come back with more suggestions myself.

You haven't mentione the length of any wire runs. This will impact the wire size you use as well. Length between panels to scc, scc to battery, battery to inverter.
 
Ok I am confused:rolleyes: But let me see if I can answer:

1. the reason I did 2S2P, is because the turbine is 24V, and therefore I had to make the battery bank 24V? so Therfore the 2S2P config gives me 24V for the PV array?
Assuming its an mppt solar charge controller, it will make the voltage appropriate for the system side.
The higher the voltage on the pv side the less voltage drop as a percentage.
Please post the details from the back of one of the panels as well as a product link for the solar charge controller.

2. So what should the wire be for the batteries and the inverter if not 6AWG?
1500 ac watts / .85 conversion factor / 20 volts low cutoff = 88.235294118 service amps
88.235294118 service amps / .8 fuse headroom = 110.294117647 fault amps
The means 4 awg pure copper wire with insulation rated for 105C and a 150 amp fuse.
Class t for the battery fuse.
I like mrbf for the branch fuses
3. so swap the disconnect for a breaker? If yes what size?
A double poll single throw disconnect switch is what I suggest.
4. so upgrade the 40A fuse between the SCC and the battery bank to 50A?
I suggest a 100 amp fuse.
Branch circuit fuses protect the wire not the appliance.
I have a spare 175A would that be OK? or is that to big?
A 175 amp fuse is too big for 4 awg wire.
4 awg wire gets a 150 amp fuse max.
5. for the battery to inverter what size wire and fuse would you recommend?
4 awg with a 150 amp class t fuse
6. You lost me on bus bars! never mind fused bus bars. What are they and where would they go?
This is a busbar
This is a fused busbar
 
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BusBar, but pick Power Bars. As you have 4 connections to the battery Positive, and the same on negative. This four post will work. https://www.bluesea.com/products/2104/PowerBar_600A_BusBar_-_Four_3_8in-16_Studs (They also have some with 8 posts.)

Then have this; Battery positive -> FUSE -> cable -> positive BusBar -> fuse -> cable. That is a BusBar fuse and cable for each device.
The shunt must be on the battery negative. Unless it is a shunt I have not met. Battery negative -> cable->shunt-> cable-> negative BusBar.
There is a tiny inline fuse for the positive power to the shunt. That fuse is at the BusBar.
If all the negative doesn't go through the shunt it doesn't measure anything.

Fuses protect wires. Size the wire gauge using a voltage drop table. Then size the fuse to protect that cable. I don't know the selected wire/cable gauge, so I can't guess the fuses are right.

With MPPT you want more voltage than battery voltage. Nominal 24V battery needs more than nominal 24V through a MPPT. The CC will have a limit on what panel voltage and ampere it can handle. I think we need be up close to that, Better brains than mine will chip in here.

I don't know modern wind turbine. Does it need a dump load? If so I would probably heat a water tank.
 
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Smooth/Derpsy Thanks folks. So second attempt but still have questions. I have attached the pdf and jpeg.

See new layout, notes/questions:

1. I split the battery side in two for simplicity ( I realize batteries don't have 2 pos and 2 neg!)
2. I changed the PV to series, that was an eye opener even after weeks of research about the MPPT controller!
3. I am still a little confused on the bus bars, but do I have the general principal right?
4. Smooth why in the links you sent is the fused bus bar cheaper? I would have assumed more expensive or do they work together?
5. Is the DC disconnect OK or should I send it back and get a breaker, if so what type and ratings? ( I have attached panel specs below in jpeg.)
6. Should I still use an inline mc4 fuse? if so is 15A OK and I assume it just goes on positive?
6. I assume I am right the controllers (both) have to attach direct to battery and not bus bars?
7. Am I missing any other fuse points? battery to bus bars?
8. Derpsy you rightly pointed out I had the shunt/monitor all screwed up! Is it OK now? so the B- to the neg bus bar and the P- back to the negative bus bar? and obviously the B+ to the pos bus bar which i assume is just for power?
8. Finally wire gauge, this really has me confused! I have plenty of 1/0, 6AWG, 4AWG and 10AWG PV cable. Currently here was my thinking:
* The wire from the panels to disconnect (or breaker) and then to controller is all PV 10AWG, good?
* 6AWG from controllers to batteries? good? Should the wind controller pos battery line also have a fuse?
* I am totally confused on the Battery wire connections for the serial and parallel connections, 1/0, 4 or 6?
* Like wise the B- from shunt to bus bar and also pos bus bar to inverter
* Wire from pos and neg batteries to bus bars?
* And finally for the battery series and parallel connections do all wire lengths need to be equal? Not sure how you do that but asking!

Once again I really appreciate the help.
 

Attachments

  • solar setup 2.pdf
    183.1 KB · Views: 7
  • eco worthy panel specs..jpg
    eco worthy panel specs..jpg
    85.8 KB · Views: 3
Smooth/Derpsy Thanks folks. So second attempt but still have questions. I have attached the pdf and jpeg.

See new layout, notes/questions:

1. I split the battery side in two for simplicity ( I realize batteries don't have 2 pos and 2 neg!)
The solar charge controller and wind turbine should be connected to the busbars.
The systems we make look like a ladder.
The busbars are the risers and the circuits are the rungs.
2. I changed the PV to series, that was an eye opener even after weeks of research about the MPPT controller!
We need to know the max voltage the solar charge controller can accept on the pv side to make sure the panel voltage + allowance for temperature coefficient doesn't burn up your controller.
3. I am still a little confused on the bus bars, but do I have the general principal right?
See my response to #1.
4. Smooth why in the links you sent is the fused bus bar cheaper?
Cheaper than the non fused busbar?
My guess is... its cheaper because it only has 4 studs, one of which is un-fused.
The un-fused position should be used for the battery because the battery gets fused as close as possible to the battery positive terminal.
I would have assumed more expensive or do they work together?
Not sure what you are saying here.
5. Is the DC disconnect OK or should I send it back and get a breaker, if so what type and ratings? ( I have attached panel specs below in jpeg.)
You don't need over current protection until you get to 3 strings of panels.
A breaker is over-current protection.
That disconnect switch should be fine.
6. Should I still use an inline mc4 fuse? if so is 15A OK and I assume it just goes on positive?
See response to #5.
6. I assume I am right the controllers (both) have to attach direct to battery and not bus bars?
See response to #1.
7. Am I missing any other fuse points? battery to bus bars?
The battery should have a 150 amp class t fuse as close to the battery positive as possible.
The turbine circuit will land on a 100 amp fuse at the positive busbar and an unfused stud on the negative busbar.
8. Finally wire gauge, this really has me confused! I have plenty of 1/0, 6AWG, 4AWG and 10AWG PV cable. Currently here was my thinking:
* The wire from the panels to disconnect (or breaker) and then to controller is all PV 10AWG, good?
10 awg is fine because the voltage is relatively high and the current is low.
* 6AWG from controllers to batteries? good?
6 awg from the controllers to the busbars is good.
100 amp fuse on the positive busbar.
Should the wind controller pos battery line also have a fuse?
Yes
* I am totally confused on the Battery wire connections for the serial and parallel connections, 1/0, 4 or 6?
4 awg just to consolidate the BOM=bill of materials.
* Like wise the B- from shunt to bus bar and also pos bus bar to inverter
4 awg from the batteries to the busbar as well.
* Wire from pos and neg batteries to bus bars?
4 awg.
* And finally for the battery series and parallel connections do all wire lengths need to be equal?
The series connections should be the same length and the parallel connections should be the same length.
The series and parralel connections do not need to be the same length.
The wires from the busbars to the batteries do not need to be the same length.
 
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Is this your solar charge controller?
If yes, it has max pv voltage of 100 volts.
Your panels have an VOC=open circuit voltage of 21.6 volts.
4 in series is 86.4 volts which should leave enough headroom for your solar charge controller.
I'm not a PV guy though so another set of eyes on this would be good.
 
This is what the core of the system will look like.
I omitted the shunt positive connection for simplicity.
In reality it will be stacked on one of the other positive studs.
Code:
positive
|<->class_t_fuse<->battery<->shunt<->|
|->fuse->inverter------------------->|
|<-fuse<-solar_charge_controller<----|
|<-fuse<-turbine_controller<---------|
                              negative
Notice the directions of the arrows.
 
Once again thanks for the help I think I am getting there. After some more reading I have decided to go with the lynx distributor as the fused bus bar solution.

Can you look at the new layout and see if I have it right? Especially the shunt/battery monitor part.

I think I only have six outstanding questions:

1. what size fuse for the wind controller?
2. what size wire for the actual battery bank? (I followed the advice for the other stuff, still correct?)
3. What size wire from the + battery bank to the bus bar?
4. Do I need a battery disconnect between the battery bank and input on the pos bus bar? I have seen other setups have them? I have ordered a blue sea battery on off switch in case.
5. Do I need a fuse between the pos battery bank and bus bar? or will the disconnect suffice?
6. Smooth you mentioned t class fuses? Is that for all of the fuses?

Once again thanks for putting up with what I assume are dumb questions. Much appreciated.

Best Regards.
 

Attachments

  • solar setup 3.pdf
    115.7 KB · Views: 8
Once again thanks for the help I think I am getting there. After some more reading I have decided to go with the lynx distributor as the fused bus bar solution.

Can you look at the new layout and see if I have it right? Especially the shunt/battery monitor part.

I think I only have six outstanding questions:

1. what size fuse for the wind controller?
6 awg gets a 100 amp fuse.
2. what size wire for the actual battery bank? (I followed the advice for the other stuff, still correct?)
4 awg, pretty sure I said this already.
4 awg gets a 150 amp fuse.
3. What size wire from the + battery bank to the bus bar?
4 awg, I think I said this already. Remember the BOM(bill of materials)
4. Do I need a battery disconnect between the battery bank and input on the pos bus bar?
No but its a nice to have.
5. Do I need a fuse between the pos battery bank and bus bar?
Yes 150 amp class-t, pretty sure I said this already.
or will the disconnect suffice?
It will not suffice.
6. Smooth you mentioned t class fuses? Is that for all of the fuses?
Just the battery fuse.
The branch circuits each get a mega fuse as that is the fuse that lynx distributor is designed for.
 
one more dumb question, I am looking at the mega fuses and some reference a voltage? Can I pick any or do i have to pick a specific voltage.

Thanks.
 
Wow they don't have a lot of selection in 58 volt fuses.
Oh Victron. :)
 
Well aren't you nice, hey man just learning!

And once again thanks for all the help Smooth. Its much appreciated.
 
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