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DMC-Orangeville
Audi eTron & John Deere 5100E
-Canada only-
The Canadian Electrical Code (CEC) changed this year regarding rooftop solar. Arc fault protection is now required. In the next edition, they will also require remote shutdown of the panels, in the event of an emergency. Fire is a good example.
There have been a number of cases where the panels, typically rated at 600-1000 volts DC, have had a fault. On a rooftop, it's a real issue, as it is REALLY hard to terminate a high voltage DC arc. As such, all new installations require arc fault protection. This can be built into string line inverters (such as Enphase, for example) and into some* combiner boxes. As the string line inverters are mainstream now, they have taken over the rooftop market. I don't believe these will be available with the new Tesla roof. (Where would you put them ?)
The remote shut off is going to be passed due to the peril to firemen and others. If the house has a fire, and it's sunny out, the panels are live, and pushing power to the inverters/batteries/line. The new requirement will insist that each panel can be remotely "disconnected". This will limit the danger to those who might have to work on the roof, or put out a fire......
*there are a number of combiner box manufacturers who are working on arc fault solutions. I know of one with a few installations - Mersen. Most of the mainstream combiner box manufacturers don't offer a rooftop solution for Canada, and have left this to the string line inverter folks.
In any case I do not believe Tesla has addressed this for Canada. We'll see.........
The Canadian Electrical Code (CEC) changed this year regarding rooftop solar. Arc fault protection is now required. In the next edition, they will also require remote shutdown of the panels, in the event of an emergency. Fire is a good example.
There have been a number of cases where the panels, typically rated at 600-1000 volts DC, have had a fault. On a rooftop, it's a real issue, as it is REALLY hard to terminate a high voltage DC arc. As such, all new installations require arc fault protection. This can be built into string line inverters (such as Enphase, for example) and into some* combiner boxes. As the string line inverters are mainstream now, they have taken over the rooftop market. I don't believe these will be available with the new Tesla roof. (Where would you put them ?)
The remote shut off is going to be passed due to the peril to firemen and others. If the house has a fire, and it's sunny out, the panels are live, and pushing power to the inverters/batteries/line. The new requirement will insist that each panel can be remotely "disconnected". This will limit the danger to those who might have to work on the roof, or put out a fire......
*there are a number of combiner box manufacturers who are working on arc fault solutions. I know of one with a few installations - Mersen. Most of the mainstream combiner box manufacturers don't offer a rooftop solution for Canada, and have left this to the string line inverter folks.
In any case I do not believe Tesla has addressed this for Canada. We'll see.........
I'm not in Canada but being a solar system owner this caught my eye. In my area a solar system is required to have a master disconnect on an external wall that emergency personnel can access to isolate the system. Is what you are describing different from that? You make it sound like each individual panel must be capable of being shut down "remotely", whatever that means. But I find it hard to believe this requirement mean each panel has to be individually controllable.
DMC-Orangeville
Audi eTron & John Deere 5100E
That's where it is heading in Canada. Not code yet, but proposed. The thinking is that all of the feeder cabling is still live. The master disconnect would take out the power at each panel via Power Line carrier, or RF. It's going to be a lot simpler if each panel has a string line inverter. I have seen a system, GreenEye/GreenBrain, from Europe, that will do this. I'm sure there are others. They are cost prohibitive currently, and not a requirement. I haven't seen them installed anywhere.
The new arc fault combiner boxes are in play now. Mostly commercial use. They have some "bugs". Nuisance tripping - especially if the solar array is undersized. Partly cloudy sunrises can be an issue. Most of the Canadian rooftop installations use Enphase string line inverters with arc fault protection in each inverter. I suspect it will be relatively inexpensive to add some kind of remote shut off to this, and meet the future requirement.
Falkirk
Member
When you say string line inverters you do mean micro inverters right? I usually think of string inverters as the one or two inverters in a system and micro inverters per panel like I have.Good to know it's another safety feature we get from using them.
Thanks
DMC-Orangeville
Audi eTron & John Deere 5100E
Yes micro inverters. The term "string line" is a generic term for an inverter built into the string of each panel, as opposed to one large inverter, which is fed by a group of panels, via a combiner box.
Since the new code has only been in effect since May (in Ontario - other provinces will vary), I'd be interested to know if your roof has the arc fault protection included. When was it installed?
Falkirk
Member
Mine was installed in March. I don't remember hearing about this during the install process or design.
