Need advice on drawings

[sdold]

I think what's happening is that even though you can show calculations for the uplift forces, fastener strength, down forces (weight, wind), there is still the unanswered question of whether or not the roof structure can support the loads. Some cities don't require engineering if the weight is less than some figure, like 5 psf. Other cities apparently require engineering for anything. My city was sort of in between, they told me I needed an engineer to look at it, but when I told them the dead load of the panels made live loads (like workers) impossible, that satisfied them. Or else they were tired of me and just wanted me to leave.

I think if you can use a tool like Ironridge or ASCE 7-10 to figure the loads caused by the panels, it would be worth a few hundred dollars to pay an engineer to look at the structure and sign it off if it makes the rest of the job go smoothly. In CA, I believe the permit fees are limited to administrative costs only. Regarding permit fees: My fees were originally around $600, and when I sent them this link http://www.solarpermitfees.org/SolarPermitLawsSumCA.pdf, the fee dropped to about $300.

[Sunking]

$500... is that how much it cost? I had no idea, I thought the whole complete permit paperwork will cost that much

Permitting is a whole other issue. Depending on where you live, permit cost are based on Project Dollars, a percentage, plus Inspection Fees. Getting your drawings and plans is none of the Jurisdiction problem, you own that problem and all expenses that come with it. Us engineers are like doctors and lawyers, we did not spend 8 to 16 years in college to work for free.

Yep it would cost you $500 for me to review and stamp your plans, that is if I approve. If not you get to do them again at added cost. After 4 or 5 tries you realize you just should have paid me $1000 to do the plans and submit to the Planning Office. I would bill you every time you walked in my office just like a Doctor or Lawyer.

I don't know what city you live in, but some jurisdictions will only accept Stamped Drawings and Plans by a PE. If that is the case in your jurisdiction, you can draw and calculate until you grow old and they will not accept anything from you. Makes things real easy on a City, County, or Jurisdiction. Relieves them of responsibility and having to keep people on the payroll to examine building plans. You bring in your Stamped Drawings and the clerk with a High School education making minimum wage issues you a permit. If anything goes wrong and there is a law suite, whoever you contracted to do the design gets held responsible, the City gets off free.

[J.P.M.]

WOW! you guys give up so easy

The Questions that i asked are half the answer, I am sure i'll be able to find a solution even if i have to read a beginner's book to Architectural engineering.

I need to do more research and come up with a solution, I have a long holiday weekend and i am sure the answer is out there.

$500... is that how much it cost? I had no idea, I thought the whole complete permit paperwork will cost that much

I kind of suspect it will take more than you envision, but good luck. I'd not take the task as lightly or cavalierly as you seem to be treating it.

[GreenTeeCrazy]

WOW! you guys give up so easy

The Questions that i asked are half the answer, I am sure i'll be able to find a solution even if i have to read a beginner's book to Architectural engineering.

I need to do more research and come up with a solution, I have a long holiday weekend and i am sure the answer is out there.

$500... is that how much it cost? I had no idea, I thought the whole complete permit paperwork will cost that much

[tehan]

Hello again.

The inspector is requiring me to show them that the roof can hold the weight of:

-dead load
-snow load
-solar system weight
etc...

Any idea on how to put all the numbers together to come up with a number that shows the roof can support atleast 70 psf?

The online design tool on the IronRidge website will do all of these calculations for you. I would at least try that and see if the inspector will accept it. If not, go to a PE because it's unlikely the inspector will accept anything your do yourself.

[Sunking]

Any idea on how to put all the numbers together to come up with a number that shows the roof can support atleast 70 psf?

The answer cost $500, I throw in my PE Stamp for free.

[J.P.M.]

Hello again.
I am not holding no one responsible in this forum, all i say is thanks for the support.

The inspector is requiring me to show them that the roof can hold the weight of:

-dead load
-snow load
-solar system weight
etc...

My roof is:
16" rafter spacing
2" x 6" x 20'
23 degree angle

Any idea on how to put all the numbers together to come up with a number that shows the roof can support atleast 70 psf?

Since you ask:

1.) Get the structural plans/drawings/calcs for the building/structure.

2.) Get a copy of ASCE 7 and calc all the required loads.

3.) Check the structure to see if it will withstand the imposed loads calc'd in 2 above.

Or,

4.) Find a structural or other engineer w/ a P.E. license/stamp who's professionally knowledgeable in structural and ASCE 7, and have 1, 2 & 3 above done by that individual. There is probably more to it than you may think.

[GreenTeeCrazy]

Hello again.
I am not holding no one responsible in this forum, all i say is thanks for the support.

The inspector is requiring me to show them that the roof can hold the weight of:

-dead load
-snow load
-solar system weight
etc...

My roof is:
16" rafter spacing
2" x 6" x 20'
23 degree angle

Any idea on how to put all the numbers together to come up with a number that shows the roof can support atleast 70 psf?

[inetdog]

And, for the casual readers, note that we are talking about the grounding wires (EGC, green or bare) not the grounded neutrals (white or gray). The neutrals from different branch circuits must never be connected except at the source panel of the branch circuits.

[foo1bar]

How sure are you of this statement, cause it will my life a lot easier

I believe this is the relevant code:
250.148 Continuity and Attachment of Equipment
Grounding Conductors to Boxes. Where circuit conduc-
tors are spliced within a box, or terminated on equipment
within or supported by a box, any equipment grounding con-
ductor(s) associated with those circuit conductors shall be con-
nected within the box or to the box with devices suitable for
the use in accordance with 250.148(A) through (E).

So, if it's just a pass-through for the wires going to jbox2, *I* would interpret this as not strictly requiring the EGC for jbox2's connections to be connected to jbox1's ground terminal.
BUT if you spliced the wires inside jbox1 it would require both EGCs to be tied to the box (and therefore to each other).

That's *my interpretation*

My interpretation is also that there's nothing that says you can't still tie them together in Jbox1.
And it can be a reversible splice since it's an EGC and not a GEC. (You should double check to be sure enphase installation is EGC's not GEC's - but I'm pretty sure the "ground wire" is an EGC.)

However I am not the one doing the installation nor the one inspecting it. I'm just an un-credentialed semi-anonymous person on a free message board

[GreenTeeCrazy]

Unnecessary IMO.

I believe all your ground wires within Jbox1 have to be connected together

How sure are you of this statement, cause it will my life a lot easier

[foo1bar]

Correct about the M250
#6 is for the rails and the Solar modules ground.
is it ok to have the ground wire be installed as a "n" shape? start from 1st rail go up to the 6th rail then connect back at the 1st rail again?

Unnecessary IMO.

I believe all your ground wires within Jbox1 have to be connected together. So you'll have one that leaves there for Jbox2

You may be able to just use the enphase cable for grounding the racking - I'll leave that up to you to determine.
If you can't, it's easy to run a bare #6 from each Jbox to the 3 bottom rails of the panels (only need to hit 1/2 the rails with ironridge - the bonding mid-clamps bond the other rail via the modules).
If you go that path you will need an "Ironridge grounding lug" or some other means to bond the #6 to the rail. Mine could fit under my panels and be hidden by them - but since I wasn't sure if there'd be clearance, I made sure I had sufficient wire to get to the edge of the array and run up alongside the panels.

[GreenTeeCrazy]

I wish i had known about that form

I'll wait til i hear from the Building permit Dept.

[JFinch57]

Correct about the M250
#6 is for the rails and the Solar modules ground.
is it ok to have the ground wire be installed as a "n" shape? start from 1st rail go up to the 6th rail then connect back at the 1st rail again?

With my Unirac I don't need any additional ground wires on the roof. The inspector has also approved it. I used #10 for my ground mount M190 system.

[tehan]

Correct about the M250
#6 is for the rails and the Solar modules ground.
is it ok to have the ground wire be installed as a "n" shape? start from 1st rail go up to the 6th rail then connect back at the 1st rail again?

You can read more at https://enphase.com/sites/default/fi...stem-v2703.pdf

but the bottom line is:

"In an Enphase Microinverter System, if the microinverters and modules are bonded to the racking
assemblies with the use of listed and approved grounding clips or grounding components, the equipment
grounding conductor provided to the microinverters through the Enphase Engage Cable may also be
used to ground the other photovoltaic system components."