diy solar

diy solar

How close to failure is this MPPT+PV package and is there a way to protect against high voltage?

I would use the IMO, I'm not a huge fan of MC4's mixed from different manufacturers. Too many differences for a good connection and over time the connection can fail with mismatched parts. Between panels where it's a string in series is OK because all the panels would have the same MC4. It is when you make the connections at the string positive and negative where a problem can occur. There is not a standard the connectors are manufactured to.

As for how to run the conduit, I always prefer gravity to shed water so I would probably have a 180 degree bend from above to enter and and exit on the bottom. If you do not have that option, then you can use a Myers hub fitting like I have at the top of the box in this photo with a threaded pvc fitting. The Myers hub will have an oring on the face for sealing purposes. https://www.grainger.com/product/52...I8f286J0LZ5F_m7PrLcaAkumEALw_wcB&gclsrc=aw.ds

PV array box.jpg
 
I will have the 3/4" PVC conduit running along the way with a pair of 8AWG and the ground cable in it. I just don't see how to physically add the disconnect at eye level mounted on the wall and having the conduit coming from the roof.

One of my city inspectors rejected exposed horizontal runs of PVC. Said only vertical (from box to under ground). So I replaced with rigid.

I have a 75' run of 2" exposed along concrete wall, which I ran some data wire in. It expands and contracts in the sun, going wavy and then pulling a conduit body to the point of breaking. It also gets sunburned.

I've since seen gasketed slip-joints for PVC.
 
One of my city inspectors rejected exposed horizontal runs of PVC. Said only vertical (from box to under ground). So I replaced with rigid.

Yep, always hated seeing that.

I have a 75' run of 2" exposed along concrete wall, which I ran some data wire in. It expands and contracts in the sun, going wavy and then pulling a conduit body to the point of breaking. It also gets sunburned.

I've since seen gasketed slip-joints for PVC.
I have one on my array, it is under the box with the SPD and breakers. Concrete base doesn't give much. You can see the slip joint in this photo. I'm a little particular how I do things.


MT Solar mount.jpg
 
better to combine strings at the SCC
That’s what I did. I seem to have electricity.
What do you think would be easier to mount on the exterior house wall: a terminal-type DC disconnect (similar to IMO) or a MC4 -type DC disconnect (similar to DIHOOL)?
Since IMO is being referenced here as a known serviceable device and is inexpensive I would pick that regardless; never mind the fail points are less, and the waterproofing more dependable.
 
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I would use the IMO, I'm not a huge fan of MC4's mixed from different manufacturers. Too many differences for a good connection and over time the connection can fail with mismatched parts.
Got it and understood. (y)

As for how to run the conduit, I always prefer gravity to shed water so I would probably have a 180 degree bend from above to enter and and exit on the bottom.
Got it! I can easily avoid the horizontal run (the original idea was purely aesthetics) and simply do a vertical conduit run down the house.

then you can use a Myers hub fitting like I have at the top of the box in this photo with a threaded pvc fitting. The Myers hub will have an oring on the face for sealing purposes. https://www.grainger.com/product/52...I8f286J0LZ5F_m7PrLcaAkumEALw_wcB&gclsrc=aw.ds
If I have a vertical conduit running down the house, will I be able to place the IMO centered with the conduit? And will this Myers Hub work for this condition or another type of hub fitting?




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One of my city inspectors rejected exposed horizontal runs of PVC. Said only vertical (from box to under ground). So I replaced with rigid.
Yes, I guess it was originally a good idea in my case for aesthetics purposes but now I see it is not a good idea. I want to keep it simple and easy for the install, so I'll bring the PVC conduit straight down the house.

(y)
 
Got it and understood. (y)


Got it! I can easily avoid the horizontal run (the original idea was purely aesthetics) and simply do a vertical conduit run down the house.


If I have a vertical conduit running down the house, will I be able to place the IMO centered with the conduit? And will this Myers Hub work for this condition or another type of hub fitting?




View attachment 158397
Not centered, the knockouts are on each side. Could a hole be drilled in the center where you indicate? Probably not, that is where the screws are located to hold the front cover to the base.
 
Not centered, the knockouts are on each side. Could a hole be drilled in the center where you indicate? Probably not, that is where the screws are located to hold the front cover to the base.
Understood.

How about the connection between the PVC conduit and the drilled hole? Should I use the same Myers hub fitting or another type?
 
Myers hub on the box with a threaded PVC fitting. Sealant on the threads before threading it into the Myers hub.

(y) (y)

I'll wait to buy the PVC conduit before buying the hub... likely I'll go with a 3/4" PVC but if I'll just be running a 8AWG set + ground maybe 1/2" PVC will do it.

Thank you!
 
Myers hub on the box with a threaded PVC fitting. Sealant on the threads before threading it into the Myers hub.
I'm committing to the 32a IMO switches. After seeing what goes into installing them and multiple advocates for them. also price is right. I haven't seen much better. Also I'll be able to use the same ones for all 4 or 5 arrays. About 1/3rd the total wattage are completely different panels but will still work perfectly for that.
 
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