Boss Lady says learn on the PowMr 3k inverter/charger + 8 100w panels or it's COAL in my stocking

WYtreasure

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Just updated the attachment and a successful search for a 150a Class T fuse with holder (thanks rmaddy).
 

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rmaddy

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4AWG between the panels and the AIO seems overly large. You only have 13A and at 67V. For the distance at that voltage and current I would think 8AWG would be plenty big enough to keep the voltage drop low.

You won't find a 160A Class-T fuse. 150A or 175A can be found at donrowe.com.

You should update your diagram with all wire gauges and rough lengths so people can give you a sanity check.
 

WYtreasure

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4AWG between the panels and the AIO seems overly large. You only have 13A and at 67V. For the distance at that voltage and current I would think 8AWG would be plenty big enough to keep the voltage drop low.

You won't find a 160A Class-T fuse. 150A or 175A can be found at donrowe.com.

You should update your diagram with all wire gauges and rough lengths so people can give you a sanity check.
4 awg will be 55' long and is oversized for this build. Future expansion may want 4 awg, so not taking any chances. Buying wire one time.
Just scored the 150a Class T fuse and holder, thanks to you. (y)

Good idea, updated diagram in the works.
 

rmaddy

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You won't be able to use MC4 connectors with 4AWG so you might need a combiner box so you can wire up the panels in parallel to the 4AWG wire. Also make sure the PV connectors on the AIO can handle 4AWG wire.
 

WYtreasure

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At the moment I am unsure what to do about grounding/bonding to complete the picture.
Note the "?" in the red/blue oval, left side of diagram.Untitled 12.png
 
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wattmatters

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At the moment I am unsure what to do about grounding/bonding to complete the picture.
Note the "?" in the red/blue oval, left side of diagram.
What does the green connection to/from the AC in/out represent? If that is a ground/earth wire, then the unit is grounded.
 

WYtreasure

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What does the green connection to/from the AC in/out represent? If that is a ground/earth wire, then the unit is grounded.
Thank you for helping me find an error. I thought the unit provided AC ground out, it does not.

The green going in "AC IN" is ground from the house. I agree with you the unit is grounded at that time.
Whenever I have the unit plugged into the grid it will be grounded through the house ground.

I will need to connect the "case ground" to ground so that when the unit is NOT plugged into an AC outlet grounding will still be provided.

The additional ground wire between the unit and house ground concerns me because of the possibility of creating a "Ground Loop".

(edit: drawing updated) to reflect the All In One unit only provides for Load/Neutral AC OUT.
 
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wattmatters

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I will need to connect the "case ground" to ground so that when the unit is NOT plugged into an AC outlet grounding will still be provided.
Can you just leave AC in connected to an AC outlet?

I thought the unit provided AC ground out, it does not.
Interesting. Different here in Australia, we have an earth on the AC out as well as AC in.

You have a different challenge. I'll leave comment on that to the earthing experts.

Thank you for helping me find an error.
Amazing isn't it how we often never see such things ourselves despite them staring us in the face!

I've often though about doing up a schematic of my system, but I give up as it's complicated!
 

Rednecktek

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Your case ground would connect to the ground bar in your sub panel, the sub panel connects up to the house ground.
 

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CamoGreg

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I struggle to understand N-G bonding as well.
So take anything I say as just talking to myself while I try to understand.

My thought is that you are indeed grounded and have the bond at your Grid AC source. And as long as the entire connection isn't "unplugged", that ground and bonding will remain.

RV systems will get into trouble because they completely unplug from the grid......ground and all.
The RV ground gets transfered to the chassis. But on split phase, the neutral bonding is lost unless the inverter has a relay that creates a N-G bond at the chassis once it doesn't have a Grid AC connection. That's two entirely different grounds.

Again, I'm not to be trusted with this, but I think since you're hardwired to the grid, your ground is always an earth ground and doesn't have to switch to a chassis ground like an RV.

My MPP LV24/24 had to have a relay installed to create a chassis N_G Bond on a cargo trailer. A relay broke the chassis bond and transfered that bond back to the pedastal when plugged into shore power. I believe many inverters such as Victrons will do this internally.

I think as long as all connections to the Grid AC aren't completely removed, you're good.
 

WYtreasure

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Your case ground would connect to the ground bar in your sub panel, the sub panel connects up to the house ground.
Here's the latest drawing.

Sounds like a 2 pole disconnect would be appropriate for those times I do not want the grid to be messing with my system.
The ground, which is mine and not the grid's; would remain connected while Hot & Neutral will disconnect.

I am still concerned about creating a "Ground Loop". Untitled 16.png
 

NVS

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WY, where are you at now with setup, and how is the powmr working?
 

WYtreasure

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WY, where are you at now with setup, and how is the powmr working?
I'm getting ready to get ready to assemble the system. Bobert and HARG Hunter run the PowMr, they or some of the threads they have contributed to might be of more help.
My PowMr 3000W Solar Hybrid Inverter, 24V DC to 110V-120V AC, 60amp MPPT Charge Controller
Model: HF2430U60 AKA: POW-LVM3K-24V is holding the workbench down really well.

I can tell you, finding the proper ring terminals for the battery connections was a pain in the butt, so here's the info.
The positive and negative battery connection uses a screw, the diameter is 4.84 mm, 0.1905 inches, 3/16".
The 140 Amp ring terminals I purchased separately fit much better than the ones I received with the controller.
Lug size: 4 awg x #10 (M5). Most folks use 2 awg or larger for battery cables. My system is smaller than most.
The factory screw, diameter: 4.84 mm, 0.1905 inches, 3/16", fits the stud hole diameter: 5.3 mm, 0.21 inches, 27/128" very well.
Selterm is the ring terminal manufacturer and they do make nice, heavy duty, closed end, copper lugs. Selterm Part number: MDS0410U.
 
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WYtreasure

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I'm ready to get ready for a dozen projects, the stupid boat just won't take me up to my place in the mountains! :D

Have you had any issues with the lower VoC limits or did you find a good setup on the panels?
I'm ready to build a few myself if the stupid snow and ice would go away. Maybe I will be making volts before you head upstream.
I believe I have a nice comfort zone with 67 vdc going into the controller. My new smoke detectors will let me know if I am correct.
I'm using 3 breakers in the combiner box. Each incoming string gets it's own breaker, combine strings and depart the box from the third, upside down breaker.
Here's the latest bar napkin. ;) DRAWING UPDATED TO #499 IN POST #61

Plan 498.png
Here's my idea of a fused disconnect.
Siemens SIE GF222NA disconnect.jpg
EDIT#1 Array description fixed.
EDIT#2 Reference to Post #61
 
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TorC

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55' of 6ga for 13A seems a little bigger than you need. I'd check line loss and see what makes sense here. BTW, I think you reversed your panel arrangement descriptor.

Continuous output of a 3kW 120V inverter is 25A. Typically a 30A house breaker will use 10ga. Nothing wrong with 8ga here, but not really needed for such a short run. However…

If your grid input is really a 50A breaker, I'd recheck that wire. IIRC, that should be 8 or even 6 for 50A. If your inverter can pass the whole of that through, then you should must use at least the same wire for the inverter output.

Looks like a nice starter system you've got going there.
 

WYtreasure

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Great observations Torc. Thank you

I don't seem to be able to fit my ideas into the norm.
55' of 6ga for 13A seems a little bigger than you need. I'd check line loss and see what makes sense here. BTW, I think you reversed your panel arrangement descriptor.
I hope my little system grows to 1600 to 2000 watts when it grows up. 6 awg is to accommodate that growth.

Panel arrangement descriptor FIXED. (y)
 

TorC

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A larger wire never hurts anything except your pocketbook, and maybe your frustration as you install it. According to your numbers, going to a 4S3P panel arrangement will be 19.5A, which is within the standard ampacity of 12ga. 55' isn't that long. A common house is likely to have a couple 20A circuits on 12ga wire that are that long. Upsizing a little for voltage drop is sensible. You get a 2.65% voltage drop with 10ga for 67VDC at 13A. That goes down as the panel output amperage goes down.

That said, finding identical panels when it comes time to upgrade isn't always easy. If you're reasonably lucky you'll at least find something close that doesn't cost too much peak power, but it's more limited than running them to a second SCC, which also gives you redundancy so your system isn't completely down in the event of failure. For your numbers, with 67V strings, adding an 80V string in parallel would leave about 16% of the new power on the table. If you add an 8A panel in series with each string because voltage leaves too much unused, you leave almost 19% of the new power on the table.

For that reason, I'd still consider running a second wire for your new panels, either at time of expansion or now if you're definitely planning to expand and/or it's very hard to add a second wire. If it makes sense, you can combine old and new at the SCC instead of the roof. If you install two wires you can run your current strings back to SCC separately and combine there for lower line loss.
 
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