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Hey, this is Greg with another episode of the "Solarix Go Solar" show.....
Want to share what I found yesterday when called out to a solar install that an out of town installer did eight years ago. This was back in the early days of solar around here and this homeowner had pooled four of their neighbors together to get a good deal on grid-tied solar. Back then they each spent about $30k of which the local utility paid about half in the "once upon a time" rebate program to incentivize solar.... Anyway, the Fronius inverter was kicked off with AC voltage errors. They had had problems with this inverter in the past and it had been replaced under warranty once so everyone assumed more Fronius problems. They had called out the utility lineman to check the grid power and of course, he couldn't find anything wrong on their side.
First thing I noticed was that the leg to leg voltage at the inverter was only about 45Vac while the leg to neutral was a good 120 for both. Voltage at the solar breaker measured fine. Pulled the dedicated solar meter (required by the local utility here) and voltage is bad - so that points to the "photovoltaic utility disconnect" box. Unfortunately, the utility here takes the position that the "evil" solar power is going to be present (even when off) on the unguarded side of the switch blades and puts a padlock on these disconnect boxes for osha safety purposes.... Had to wait a day for a lineman to come unlock the box and the attached picture is what we found.
Can't really tell what exactly the installer did wrong in terminating the black conductor, but either did not get the screw tight or had a bit of insulation pinched in the terminal. I've never seen a wire cooked this bad though. This 8ga wire was literally oxidized to the point it just fell apart at the slightest touch. Like how ashes can hold their shape even though totally burned. I figure this wire had been slow cooking for its whole eight year life.
I worry about this kind of thing with my guys. If wire terminals don't get properly done, the circuit can work but have too much contact resistance, heat up and sit there and burn for a long time. Inspectors generally do not catch this kind of thing and its why there is just no getting around hiring a good electrician. (not some nation-wide franchise that hires a lot of newbie kids and pressures them into going fast). My solution? We just purchased a FLIR camera and am using it to inspect all our terminations.
Oh yes, also found they had put a GE breaker for the solar circuit in a Siemens box - maybe they thought that was OK because the A/C circuit next to it was also a misfitting GE breaker however that was a 40A breaker on a 10ga circuit..... I won't mention who this installer was, however they refused to come fix their workmanship failings saying that their 2-year warranty was up.... "The aftertaste of poor quality lasts a lot longer than the sweet taste of a low price"
That's all for now - see you next time on the Go Solar show!
Burned AC Disconnect.JPG
Want to share what I found yesterday when called out to a solar install that an out of town installer did eight years ago. This was back in the early days of solar around here and this homeowner had pooled four of their neighbors together to get a good deal on grid-tied solar. Back then they each spent about $30k of which the local utility paid about half in the "once upon a time" rebate program to incentivize solar.... Anyway, the Fronius inverter was kicked off with AC voltage errors. They had had problems with this inverter in the past and it had been replaced under warranty once so everyone assumed more Fronius problems. They had called out the utility lineman to check the grid power and of course, he couldn't find anything wrong on their side.
First thing I noticed was that the leg to leg voltage at the inverter was only about 45Vac while the leg to neutral was a good 120 for both. Voltage at the solar breaker measured fine. Pulled the dedicated solar meter (required by the local utility here) and voltage is bad - so that points to the "photovoltaic utility disconnect" box. Unfortunately, the utility here takes the position that the "evil" solar power is going to be present (even when off) on the unguarded side of the switch blades and puts a padlock on these disconnect boxes for osha safety purposes.... Had to wait a day for a lineman to come unlock the box and the attached picture is what we found.
Can't really tell what exactly the installer did wrong in terminating the black conductor, but either did not get the screw tight or had a bit of insulation pinched in the terminal. I've never seen a wire cooked this bad though. This 8ga wire was literally oxidized to the point it just fell apart at the slightest touch. Like how ashes can hold their shape even though totally burned. I figure this wire had been slow cooking for its whole eight year life.
I worry about this kind of thing with my guys. If wire terminals don't get properly done, the circuit can work but have too much contact resistance, heat up and sit there and burn for a long time. Inspectors generally do not catch this kind of thing and its why there is just no getting around hiring a good electrician. (not some nation-wide franchise that hires a lot of newbie kids and pressures them into going fast). My solution? We just purchased a FLIR camera and am using it to inspect all our terminations.
Oh yes, also found they had put a GE breaker for the solar circuit in a Siemens box - maybe they thought that was OK because the A/C circuit next to it was also a misfitting GE breaker however that was a 40A breaker on a 10ga circuit..... I won't mention who this installer was, however they refused to come fix their workmanship failings saying that their 2-year warranty was up.... "The aftertaste of poor quality lasts a lot longer than the sweet taste of a low price"
That's all for now - see you next time on the Go Solar show!
Burned AC Disconnect.JPG
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