Regulation summary for self installations

[Dan Lavoie]

I'm a handy kind of guy and very comfortable with electrical wiring. Is there a manual or a resource on the web that summarises all of the regulations specific to the installation of solar systems in on order to pass an inspection in Ontario? Thank you

[Rob Beckers]

Dan, in a way, yes: The CEC book (Canadian Electric Code) plus the Ontario supplements...

That's a pain to read through though, it reads more like a law book than anything practical.

If you tell me what the plans are I can tell you what inspectors will be looking for. We used to install (in Ontario) and still sell dozens of grid-tie systems a year to people, some doing the work themselves.

-RoB-

[Dan Lavoie]

Hi Rob, I am familiar with the CEC and some of the tables. I didn't really want to dig through a bible thick code book to find the sections related to solar installations. I was hoping to find a summary or the equivalent to the Coles Notes for solar installations in Ontario. Even simple things like the requirements for squirrel guards and labeling is very specific to solar installation and not typically required in a standard house electrical installation. Thank you

[Rob Beckers]

Dan, I don't know of any summary, unfortunately...

Section 64 deals with renewable energy systems, including solar. Certain things are more universal, such as grounding and conductors, and refer to other sections. It's not too bad though; if you tell me what the plan is (grid-tie I assume? micro-inverters? string-inverter? rooftop? ground mount?) I can give you a summary.

-RoB-

[Chris Mazereeuw]

Hi Rob, I have a very similar question/situation to Dan's original post.
I am interested in the 10kw grid-tie offered on solacity's website: for netmetering, to be installed on a shingle-roofed bungalow, and have been in contact with one of the salespersons about the additional advice offered to help with DIY installations, as stated at the bottom of the page, which he stated they do not provide, hence why I am posting here.
I would be looking for basically an SLD like this: https://www.bluepacificsolar.com/picture_library/solar-kits/grid-tie-line-drawing.jpg
to assist with my installation, along with whatever the ESA inspector is looking for.
I am also looking for a P.Eng that can review my roof as my township requires that sign-off with drawings.
Fortunately I am good on creating drawings, but have had trouble finding a P.Eng to provide that service. Any help in that regard would be helpful as well.

[Rob Beckers]

Hi Chris,

To start with the last: In case you are in Ontario, we do have a benign engineer on speed-dial that can provide a stamped structural engineering drawing. So far I believe there has been only one roof that he found unsuitable from a structural perspective. I have a list of questions to collect the info that we need to provide to him (which is better done via E-mail), and our (Solacity Inc.) fee is $700 plus tax for the service. That should be a couple hundred cheaper than most other structural engineers, but by all means ask around.

For a net-metering install, please state the questions you have and I'll do my best to answer. We don't make drawings for people because we just don't have the man-power to do that. A single drawing easily takes an hour or more. I do have generic net-metering drawings from the days that utilities required single-line-diagrams, though they are not too helpful when it comes to practical installation.

Are you looking for a SolarEdge install, as per the drawing you posted? Things are a little easier for optimizer and micro-inverter installs, in that code does not require Rapid Shutdown (RSD) and rodent protection (squirrel guard). There have been some inspectors that did not feel those exemptions applied to optimizers, generally they will allow this though. In general, it is a very good idea to get together with your inspector before installing anything and to go over the plans with them. When you apply for a permit you'll get a paper with the inspector's name and phone number, and you get two inspections included in the price. Since there is no "rough-in" inspection for a PV system you can use one of those as an initial meeting to tell the inspector what you are planning to do and ask they they are OK with that. Inspectors like to do this too; for them it's not great to have to tell a home-owner they did it all wrong and should rip it all off the roof.

Regarding back-feeding the panel as per your drawing; There is a code rule that states you can have 120% of the busbar capacity of the panel feeding said panel. Usually the busbars in a panel are rated at the same as the panel capacity (so a 200A panel generally has 200A rated busbars), and to extend this example, that means you can feed 120% or 240 Amp to a 200A rated panel. The main breaker takes up 200A of this, leaving you with just 40A to feed from solar PV. Since breakers are sized 125% of expected Amperage, that leaves you with a maximum of 7.6 kW in inverter size. Anything larger would require a load-side tap (i.e. tapping into the line between the meter and your panel), and connecting at that point via a fused AC disconnect (the disconnect is needed anyway, and fused ones don't cost much more). In case you are backfeeding your panel, the PV breakers need to be mounted on the far end away from the main breaker, another code requirement.

Anwyay, ask away! I'll try to answer best I can.

-RoB-

[Chris Mazereeuw]

Hi Ron,
To verify, I am in Ontario.
I'm not worried about making drawings - I am well looked after in that regard - I just need the info to create them
My utility - and as far as I can tell - ESA/OESC still requires an SLD but only on or located on the disconnect for the PV installation e.g. a lamacoid, so I will be searching for that as well, but I have a few leads for that already.
I am not looking for the SolarEdge installation per se, it's just an example drawing I found.
One thing I'd like to know more about is the micro-inverter/optimizer install versus the string inverter - and what exactly is in entailed with the Rapid ShutDown (RSD) and squirrel guards? What advantages are there to both?
I've found that the Fronius string inverters will communicate with the Victron Quattro's, so in the event I want to incorporate a battery system, it seems to me the Fronius String inverter would be the way to go.
Thanks for the information regarding the OESC and feeding in through my existing load centre, in my case I am looking to do the line side tap (i.e. between the meterbase and load centre main disconnect) to take advantage of the 10kW limit for net-metering.
I have looked into it and unfortunately I do not have a "solar-ready" panel - apparently there are new-ish ones that increase the size of the bus bar in the load centre to 225A to allow for a higher rated feed in breaker.
I believe I have figured out how I am going to do the line side tap, but as you suggested I will nail down my installation plans and book a meeting with my local ESA inspector.
I believe based on code rules that the ac fused-disconnect for a 10kW system needs to be rated at 60A - can you confirm? In addition, I believe I need either a finger-safe fused disconnect, or an additional disconnect that isn't rated to break load after opening the main disconnect in the event I need to replace a fuse.
Also, with the kits provided by Solacity, is there a DC disconnect provided on the line-side of the inverter, or is one required?

[Rob Beckers]

Hi Chris,

The SLD for the Lamacoid is really a very simple abstraction, no more than a few lines, and pretty trivial to make.

Micro-inverters make it so you only have to deal with AC wiring. Some people find this easier vs. having to do DC wiring for the panels. Optimizers stilll have the DC wiring, but as mentioned both optimizers and micro-inverters are exempt from RSD and squirrel protection.

Squirrel protection is a pain to install, and IMO ugly to look at, but if done right it will keep the critters away from the underside of the panels. If you want or need that depends on your situation: I live in a forest with more squirrels than I can count, and never had a problem with my panels (without rodent protection), I know of others that have continuous issues with squirrels and chewed-through wires.

String inverters are usually cheaper (though SLD and squirrel protection add money). You don't get module-level monitoring, just string-level. The big advantage is when a micro-inverter or optimizer fails (and they will); replacing one of those means pulling panels, and you hope the manufacturer still exists when it happens. String inverters have a much smaller chance of failure (one inverter vs. 3 dozen of them), and is easy to replace.

RSD depends a bit on the brand. We mostly sell Fronius for string inverters and they have their own RSD boxes that make it pretty easy. It also doubles as the code-required "means to disconnect" for the DC wiring coming off the roof.

I've been told that the new code taking effect in May allows for 125% of busbar rating of the breaker panel for feeding it (up from 120%), I've yet to read through the whole book. Still, most 200A panels have 200A rated busbars, giving you 50A to work with (out of the 250A available, 200A is taken up by the main breaker, unless you can find a smaller Amp replacement for that). For a 10kW the max current is about 10000 / 240 = 42A, and breaker sizing is 1.25 x max current = 52A = 55 or 60A as the nearest available size.

Yes, a regular fused AC disconnect works fine, no additional hardware needed. Something like an Eaton CDG222NRB (https://www.westburne.ca/cwr/Category/Distribution/Residential-Distribution/Disconnect-Switches/Light-%26-General-Duty-Safety-Switches/CDG222NRB-C-H-60A-2P-3W-FUSED-SWITC/p/EATCDG222NRB-WG) will do fine. They (and similar) are widely available. This also functions as the code-required AC disconnect.

For string inverters the DC disconnect is usually build into the inverter (it is for Fronius). That meets code, no additional DC disconnect needed.

-RoB-