five.five-six
Senior Member
- Location
- california
Does $95 seem like a reasonable price for an engraved placard and stickers set?
Does $95 seem like a reasonable price for an engraved placard and stickers set?
How are you guys getting mods to the roof? I was thinking I’d rent a scissors lift but that seems rather expensive. Next thought was to buy one but then I have to store it.
Shingle hoist? Ropes?
I did read about someone putting them on a backpack but it seems that one good gust of wind and it would be curtains
One story - one guy on the ground passing to 1-2 guys directly on the roof.
Two Story - find an intermediate roof and pass from the ground to the 1st story, then the 1st story to 2nd story
Two Story Cube home - if no intermediate roof lines are available I will go to home depot and buy some regular bent steel S style hooks that will pilot into the holes in the module for grounding lugs, then bend up some 8 or 6 bare copper into a tripod/coat hangar looking thing. two points on the bottom have the S hooks attached, and the top of the triangle is twisted into an eyelet that I can thread some high tensile strength rope, or some kind of mechanical clip into. The loose end of the rope stays on the roof and I use 1 or 2 staff members who stand at the head of the ladder that's already been setup and strapped to the rafter tail. drop your hook to the ground and hook it up to the module. Pull module up the ladder, preferably while you have another staff member climbing up the ladder behind the module to keep a hand on it while the roof guys pull it up.
Resi jobs (1-2 stories) I've never considered renting a scissor lift/gradall. Big resi jobs where we're humping any more than 30 mods (or a pallet of mods depending on the module manufacturer) I'll consider a gradall but probably wont pull the trigger because of the pace of our jobs. Multifamily/commercial I'll definitely run some kind of additional machinery. not only does it help with modules, but it's really helpful to be able to drop all equipment directly to the roof.
If you are involving a utility in an electrical service upgrade there may be further restrictions.
That's $1,700 dollars, you drop it an I'll ... don't hurt yourself. Love it!! :lol:
So, I have a buddy in my aquarium club who has been with the local natural gas company for many years. He told that the gas meter needs to be at least 3 linear feet from any electrical equipment such as an inverter and that they may require you to relocate one or the other if the meter is too close the inverter. He also told me that the rule has been relaxed to only require a 3’ circle around the meter. Has anyone else ran into this?
Also, my 9-year-old made this inverter “unboxing” video on youtube. Do me a favor and watch it in a separate browser so he gets “views” on it. It means the world to him at this age and he is really excited about the 77 views it already has. Like and or comment for bonus points. Thanks
https://youtu.be/i8tscM2yuEA
Great video, "Who needs instructions?" He will go far.
I have to wonder how you can wear that shirt around your son though.
...
A few things to keep in mind for this and future installs. ( 2017 NEC).
1. THHN cannot be used in exterior raceways (EMT) on the roof. 300.38, 310.10(C)
2. Be sure to double check your local ambient temperature and the spacing height above the roof to the bottom of the conduit you will be installing.
Chances are # 10 will not be enough ampacity, especially if you are combining strings. Table 310.15(B)(16) is only accurate for ambient temperature of 86 degrees F (see paragraph at the top of the table). You have to adjust the ampacity based upon table 310.15(B)(2)(a) for your local area.
If you do not know your local ambient temperature, a guide is available for free PDF from Copper Development Association. https://www.copper.org/applications/electrical/building/pdf/rooftop.pdf
If the bottom of the conduit is less than 7/8" off the roof, you also have to add 60 degrees F to the ambient temperature for your local area. 310.15(B)(3)(c).
And if you have more than 3 current carrying conductorsin the conduit, you have to reduce the ampacity even further per Table 310.15(B)(3)(a).
It is very common in my area for a #10 to only carry 16 amps on a roof.
Your son did a great job on the video. Hope he follows up with a completed project video, maybe interviewing installer/contractor?
A few things to keep in mind for this and future installs. ( 2017 NEC).
1. THHN cannot be used in exterior raceways (EMT) on the roof. 300.38, 310.10(C)
2. Be sure to double check your local ambient temperature and the spacing height above the roof to the bottom of the conduit you will be installing.
Chances are # 10 will not be enough ampacity, especially if you are combining strings. Table 310.15(B)(16) is only accurate for ambient temperature of 86 degrees F (see paragraph at the top of the table). You have to adjust the ampacity based upon table 310.15(B)(2)(a) for your local area.
If you do not know your local ambient temperature, a guide is available for free PDF from Copper Development Association. https://www.copper.org/applications/electrical/building/pdf/rooftop.pdf
If the bottom of the conduit is less than 7/8" off the roof, you also have to add 60 degrees F to the ambient temperature for your local area. 310.15(B)(3)(c).
And if you have more than 3 current carrying conductorsin the conduit, you have to reduce the ampacity even further per Table 310.15(B)(3)(a).
It is very common in my area for a #10 to only carry 16 amps on a roof.
Wiring in EMT is fine as long as it is wet rated, i.e. of a type with a 'W' in it.
To use #10 on the roof for Solaredge strings it will need to be 90C wire, i.e. with '-2' at the end.
Thus THWN-2. Most suppliers will give that to you by default but double check.
Now for the size...
Your SolarEdge string is max 15A which is 18.75 at 125% continuous.
90C wire is rated 40A which with 4-6 conductors is 32A at 80%.
18.75/32 is .58 so that's the minimum temperature derating factor you can use. Works for me almost all the time but Ontario may get hotter than where we work. Depends on your AHJs feelings about the ambient temp you use.
Depending on the rail you used, it may be possible to stick a cell phone under the array and get pics of some of the optimizer serial numbers on the bottom of the mounting bracket. That is for optimizers mounted near enough to the edge of the array.
Otherwise, you can just fake your way through the array map and as long as you are the one doing any servicing it won't really matter. Later on if/when you have to pull up panels to find a bad optimizer you can take that opportunity to correct relevant portions of the map.
Don't ask me how I know these things. :slaphead: