DIY Self-Install in San Diego - 7.84 kW for < $1.30 / W

[bcroe]

Dang, I got them from pvlabels.com, and yeah, it looks like their filtering system isn't right. Looks like the more specific requirements are new for 2014... selecting 2014 NEC should probably have returned only red labels, but it doesn't. Thanks! I'll need to double-check the other labels now, too.

I have created and modified some signs, using a cheap on line bumper sticker service. Choose your color. Note the
bottom line of this set of signs I picked up surplus, part of a custom bumper sticker. Bruce Roe

PVsign.JPG

[SunEagle]

After review, they concluded that it would need to be moved, or another disconnect at ground level be provided, so I think we've all gotten to the same place on this. There was enough discussion about it at the office that they are going to make it the subject of next week's training meeting

They were clear that only the switch itself needs to comply with the height requirement, not the entire inverter.

I will be glad to move it, if for no other reason than it means I have an excuse to pull out the two conduit pieces I liked least and replace them to get to the new location. It drives my wife nuts when I un-do work I'm not proud of, so I had left it, but now it is out of my control.

Too bad about you needing to relocate the inverter, but in retrospect you might find that the original location was a PIA if you had to do any trouble shooting.

[sensij]

After review, they concluded that it would need to be moved, or another disconnect at ground level be provided, so I think we've all gotten to the same place on this. There was enough discussion about it at the office that they are going to make it the subject of next week's training meeting

They were clear that only the switch itself needs to comply with the height requirement, not the entire inverter.

I will be glad to move it, if for no other reason than it means I have an excuse to pull out the two conduit pieces I liked least and replace them to get to the new location. It drives my wife nuts when I un-do work I'm not proud of, so I had left it, but now it is out of my control.

[J.P.M.]

Some more reading... I think the inspector was wanting to apply 404.8 to the location of the disconnect, which states that the center of the switch in its highest position can not be more than 6 ft 7 in above the floor or platform. However, there is an exception to that which allows that switch to be located higher and accessible by portable means if it is next to the equipment being supplied. So, maybe a small reason for hope.

Edit: Here is another take on it, suggesting that if an AC disconnect is added at the inverter, and also the closest readily-accessible point, it might be ok. That might still not be less expensive or require less work than just moving the inverter, though.

Absolutely NOMB, but I suspect that while you probably don't or maybe won't need to access your inverter quite as much as I access mine, I'd not be surprised if you will still probably be getting near it for a lot of reasons more than most. FWIW, after living w/mine for 3.5 yrs., I'm glad the output screen is close to eye level and access is easy. Moving yours might be something you might be glad you did in the future. Just sayin'.

[cebury]

Some more reading... I think the inspector was wanting to apply 404.8 to the location of the disconnect, which states that the center of the switch in its highest position can not be more than 6 ft 7 in above the floor or platform. However, there is an exception to that which allows that switch to be located higher and accessible by portable means if it is next to the equipment being supplied. So, maybe a small reason for hope.

Edit: Here is another take on it, suggesting that if an AC disconnect is added at the inverter, and also the closest readily-accessible point, it might be ok. That might still not be less expensive or require less work than just moving the inverter, though.

Higher than the 6ft 7 was what my installer was balking at. He didn't know for sure, but taking the most cautious approach, considered it from the top most part of the inverter ... considering it was one unit as disconnect?. Good luck.

[sensij]

Some more reading... I think the inspector was wanting to apply 404.8 to the location of the disconnect, which states that the center of the switch in its highest position can not be more than 6 ft 7 in above the floor or platform. However, there is an exception to that which allows that switch to be located higher and accessible by portable means if it is next to the equipment being supplied. So, maybe a small reason for hope.

Edit: Here is another take on it, suggesting that if an AC disconnect is added at the inverter, and also the closest readily-accessible point, it might be ok. That might still not be less expensive or require less work than just moving the inverter, though.

There are a few exceptions, but, in general, Section 404.8(A) requires switches and circuit breakers to be readily accessible and limits the height of their operating handle to no more than 6 feet 7 inches above the platform or working surface from which they are accessed. However, Sections 690.14(D) and 705.70 permit inverters to be installed in non-readily accessible locations. This is a common scenario in residential PV systems where microinverters may be mounted behind modules, or in commercial PV systems where string inverters may be mounted on a parapet wall on a low-sloped roof. In these cases, DC and AC disconnecting means are required either within sight of - defined in Article 100 as "visible and not more than 50 feet away from" - or integrated into the inverter. Since they are equipment disconnects, they must be grouped with the inverter. Depending on the particular string inverter, a combination of internal (such as a built-in DC disconnect, which may or may not also disconnect the AC conductors) and/or external (most commonly, an external AC disconnect switch) is used. With microinverters, the plug connectors on the microinverters must be listed and identified to meet this disconnect requirement (per the Exception to Section 690.17 and the requirements of 690.33). An additional disconnect for the inverter output circuit of roof-mounted (not readily accessible) inverters is required. It must meet the requirements of Sections 690.14(C)(1), 690.17(1) and 705.22, which apply to disconnecting means for PV systems and require them to be readily accessible: installed either on the outside of a building or inside at a readily accessible point, and as close as possible to the entry point of the system

[sensij]

A new multi pole switch rated for high voltage DC, is pretty expensive. I picked up some 3 pole used ones on Eb+y,
some with fuses, some not. Do you need 4 poles for lack of a combiner box? Bruce Roe

There are two strings, combined at the inverter into a single input. I might be able to use a 2 pole disconnect with twin wire ferrule on the input, one pole for the combined DC+ and the other for the DC-, and bump up the output wire to 8 awg to handle the 30 A combined current instead of the 15 A per-circuit current.

The more I think about it, since he didn't object to the cabinet underneath the inverter/disconnect, only the height, there is a place near the garage door where the built-in drops to counter height that would probably be an OK place to put it. I'd have to put a junction box in to splice onto the existing DC wires, but at least the AC would only be shortened, and more importantly, the GEC for the AC side could remain unbroken, since it is getting shortened too. Basically, where the baby seat is in this picture. That portion of the wall is more exposed and likely to be warmer than where it is now, but at least there would be better airflow.

garage - plan B.JPG

[bcroe]

A new multi pole switch rated for high voltage DC, is pretty expensive. I picked up some 3 pole used ones on Eb+y,
some with fuses, some not. Do you need 4 poles for lack of a combiner box? Bruce Roe

[sensij]

Inspection went well... I stumped him with the inverter location. He is actually fine with the inverter where it is at, but is questioning whether the DC disconnect needs to be "readily accessible". What I have should meet the requirements of 690.15(A), but maybe not 690.13(A). He took a picture and will run it by his supervisor, and let me know in the morning.

SolarEdge sells the Firefighter Gateway as a remote shutdown option, but it costs &gt;$500, so if it doesn't fly, I'd probably just move the inverter. One other option to look into might be just a redundant disconnect, and run a third piece of conduit from where the inverter is now with the DC wires both going and coming to a disconnect that is in the proper location. I'm not sure I'll find a 4 pole, 30 A DC rated disconnect for less than the $100 or so it would take for me to go with that over just moving the inverter.

One other correction, he wanted the rapid shutdown plaque attached with rivets, not self-tapping screws. They also prefer it to be mounted on the hinged door to the MSP, not down below in SDG&E's portion of the box, but he is ok leaving it where it is. That one is sort of aggravating since the PV Plan Template the city makes available specifically states screws are OK, but whatever. Looks like I can get a light duty riveter and some rivets for around $20, one more item for the expense list.

plaque.JPG

[sensij]

Thanks for the pictures. I learned to solve those irregularity problems with a laser level. Reading the details on
your expenses wears me out. good luck, Bruce Roe

Congratulations on the new installation sensij.

Thanks... yeah, if I ever do this again, I'll get some better use out of my laser level. It helped with the conduit, but it would have really improved the rail installation. Here are a few more pictures.

main service panel: service panel - open.JPG



labeled: service panel - labeled.JPG




Finished array: array - e cropped.JPG



array - sw.JPG

[SunEagle]

Congratulations on the new installation sensij.

[sensij]

I ran it for 30 min or so this morning, long enough to verify that all the optimizers are checking in. Here is the public site... I'll have to play games with my signature or bump my old system out, I guess.

https://monitoringpublic.solaredge.com/solaredge-web/p/site/public?name=Torrey%20Santa%20Fe

[bcroe]

my roof is really wavy. Using fixed spacers to offset the rails from the tiles was a bad idea, I should have used string to set the heights of each rail in a single plane. I was able to make some adjustments as the problems became clearer (>0.5" height mismatch between rows in some places), but it isn't perfect.

Thanks for the pictures. I learned to solve those irregularity problems with a laser level. Reading the details on
your expenses wears me out. good luck, Bruce Roe

[cebury]

Beautiful details, man. Love it.

[sensij]

Also, for folks keeping score, at this point it looks like I'm over the 1.30 target in the subject by 0.05 (just under $400 over budget).

Total power = 290 * 28 = 8120 W
Total spent = 11,252.89
Total credits = 307.57 (credits come from cash back on credit cards, selling excess materials, etc)

Net cost per W = (11252.89 - 307.57) / 8120 = $1.348 / W

Below is what is has been spent so far. I don't think there will be more, but will up this post if it changes.
bom-1.JPG



Racking Detail: Bom - 3.JPG




Home Depot detail bom - 2.JPG