pgrovetom1
Member
- Location
- Sonoma California
- Occupation
- Telecom System Engineer
I'm preparing a detailed spec for a friends system I intend to be quoted by local installers in Northern California. I've been studying the various options for inverters and batteries to spec and now I'm exploring the ground mount array itself. I want the spec to be as precise and code compliant to the extent possible so I'm comparing apples and apples. I'm looking at the grounding requirements for a ground mount array about 300ft from the home. 300ft is substantial and the cost of the wires will not be cheap given the dramatic cost increases of copper wire in recent years.
In 2008 I built a system in Sonoma County and it had 4 separate arrays with each a separate string. The 4 strings returned to 2 SMA 6000 Inverters along with a #10 green ground wire. That green ground wire tied into the equipment ground and into the homes main 8 foot ground rod located near the inverters and main panel. I also drove 8 foot ground rods at each array of 4 and strung bare #6 to every panel and metal component ( 2 1/2 galvanized pipe and struts) with appropriate ground lugs. The 4 arrays were electrically ( except by the ground rods earth path) not connected even though they were about 4 feet spaced. In 2008 the local AHJ approved this arrangement. I'm now 72 and am unable to build this myself so I'm trying to create a package spec so my quotes are for the same thing as close as possible.
My friends home has a large field where I was intending to run one linear rack to carry 4 sets of panels with their 4 strings with 2 sets combined on red/black #10 in conduit carried about 300 ft to the home inverter. I was planning on including one #10 green THWN-2 ground from the combiner along with the string wires back to the main inverter at the home main panel and tied to the ground rods for the home. The linear rack ( not in spaced sections) will have a #6 bare copper wire tying all the panels together and metal parts ( as not provided by panels or racks) and return to the combiner box. There it will connect to the #10 green wire being carried back to the home and its main ground rod.
Is this done correctly and a sufficient description for a bid spec?
Since 300 ft is a long distance and #10 wire is not cheap, I want to be sure I'm using the right number of wires and gauge to meet requirements. Once I have the spec and have chosen all my components spec sheets and think its right, I will sit down with a local AHJ inspector and make sure its ok or make any adjustments needed. Then I plan on giving it to some local installers for quotes and feedback. Any feedback if this is a good strategy and if the ground mounting array grounding scheme is appropriate for a California installation is appreciated.
thanks.
In 2008 I built a system in Sonoma County and it had 4 separate arrays with each a separate string. The 4 strings returned to 2 SMA 6000 Inverters along with a #10 green ground wire. That green ground wire tied into the equipment ground and into the homes main 8 foot ground rod located near the inverters and main panel. I also drove 8 foot ground rods at each array of 4 and strung bare #6 to every panel and metal component ( 2 1/2 galvanized pipe and struts) with appropriate ground lugs. The 4 arrays were electrically ( except by the ground rods earth path) not connected even though they were about 4 feet spaced. In 2008 the local AHJ approved this arrangement. I'm now 72 and am unable to build this myself so I'm trying to create a package spec so my quotes are for the same thing as close as possible.
My friends home has a large field where I was intending to run one linear rack to carry 4 sets of panels with their 4 strings with 2 sets combined on red/black #10 in conduit carried about 300 ft to the home inverter. I was planning on including one #10 green THWN-2 ground from the combiner along with the string wires back to the main inverter at the home main panel and tied to the ground rods for the home. The linear rack ( not in spaced sections) will have a #6 bare copper wire tying all the panels together and metal parts ( as not provided by panels or racks) and return to the combiner box. There it will connect to the #10 green wire being carried back to the home and its main ground rod.
Is this done correctly and a sufficient description for a bid spec?
Since 300 ft is a long distance and #10 wire is not cheap, I want to be sure I'm using the right number of wires and gauge to meet requirements. Once I have the spec and have chosen all my components spec sheets and think its right, I will sit down with a local AHJ inspector and make sure its ok or make any adjustments needed. Then I plan on giving it to some local installers for quotes and feedback. Any feedback if this is a good strategy and if the ground mounting array grounding scheme is appropriate for a California installation is appreciated.
thanks.