# Service upgrade, add generator inlet with existing solar array



## yankeejoe1141 (Jul 26, 2013)

Hello everyone,

I went today to give a price on a potential job for a service upgrade, the house has a 100 amp service with a solar array. The home owner wants to upgrade to 200 amp and add an option to connect a 10kw portable generator during the next power outage. 

So I’m looking at the job just like a regular service upgrade and I’ll add an interlock kit, 50 amp breaker, and power inlet.

The guys friend tells me the homeowner has been getting high pricing, the homeowner tells me I’m the third one to look at the job. Now I don’t know what the other guys bid or what the homeowner thinks is high, but I’m starting to wonder if I’m missing something. This would be my first time working around a solar array.

I guess my question is: should I have to take anything special into consideration with the solar array? I’m guessing they’re just line side tapped since there’s no back fed breaker labeled solar, so I plan to put them back the same way and when the guy runs his generator the solar will be locked out by the interlock keeping the main breaker off.

Anyone think I’m missing something? For what it’s worth I’m just under $2k for the upgrade with generator inlet. 

Thanks.


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## CTshockhazard (Aug 28, 2009)

joedawson79 said:


> Hello everyone,
> 
> I went today to give a price on a potential job for a service upgrade, the house has a 100 amp service with a solar array. The home owner wants to upgrade to 200 amp and add an option to connect a 10kw portable generator during the next power outage.
> 
> ...


 Correct on the solar.


He's only been getting 'high' prices because yours is so low.




> Anyone think I’m missing something? For what it’s worth I’m just under $2k for the upgrade with generator inlet.


Yes, the correct amount of profit. Services and generator connections are "premium services". FWIW, I was already charging 2k for a 100a service change 12 years ago.


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## yankeejoe1141 (Jul 26, 2013)

CTshockhazard said:


> Correct on the solar.
> 
> 
> He's only been getting 'high' prices because yours is so low.
> ...


Thanks for the reply, I think your right about me missing out on profit, I'm suppose to drop off my quote later today and I'm going to reprint it with another $400 on there. After thinking about it more I have to figure the service is worth about $2k alone and the generator option is at least $600. I just have the benefit of doing both at the same time.

Thanks again.


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## yankeejoe1141 (Jul 26, 2013)

joedawson79 said:


> Thanks for the reply, I think your right about me missing out on profit, I'm suppose to drop off my quote later today and I'm going to reprint it with another $400 on there. After thinking about it more I have to figure the service is worth about $2k alone and the generator option is at least $600. I just have the benefit of doing both at the same time.
> 
> Thanks again.


Where in CT are you? I'm East of New Haven.


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## canbug (Dec 31, 2015)

Don't concern yourself with how someone else bids. Price it out, add labour that includes travel and picking up materials then add 10-20 percent for the " what did I forget clause".
If you get the job, great and if you don't, that's OK because you don't work for free..

Tim.


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## yankeejoe1141 (Jul 26, 2013)

canbug said:


> Don't concern yourself with how someone else bids. Price it out, add labour that includes travel and picking up materials then add 10-20 percent for the " what did I forget clause".
> If you get the job, great and if you don't, that's OK because you don't work for free..
> 
> Tim.


Thanks Tim, that's what I try to do but maybe I struggle with the 10-20 percent "what did I forget" part, I basically went to the supply house with a list of materials (meter can, panel, inlet, wire, etc.), added $100 to that for connectors and such, and figured it would be a long day so added $1000 to that for the labor and came out to $1900.

But when I think about the two jobs individually, a service upgrade being worth $2000, and a generator inlet and interlock being worth about $600, I'd lose sleep thinking I left money on the table.

Thanks again,


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## canbug (Dec 31, 2015)

Something I've learned over the years and now use to price smaller jobs like the one your looking at is" what's this job worth" and then I put a number down. Like you said, the panel change out is 2k *plus* the transfer switch. You're allowed to make money, if someone gives the job away then it's better that you don't get it.

Tim


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## CTshockhazard (Aug 28, 2009)

joedawson79 said:


> Where in CT are you? I'm East of New Haven.


Smack dab in the middle.


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## yankeejoe1141 (Jul 26, 2013)

CTshockhazard said:


> Smack dab in the middle.


Thanks, and thanks for your advise about the price too. I reprinted my quote with an additional $500 on it, but before I went to see the guy he called me and we agreed on a price over the phone, $400 more than I was going to originally ask for.


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## Coppersmith (Aug 11, 2017)

I haven't drawn this out to verify but I think you can (and would want to) have the solar system working when the generator is operating. In a power outage, the homeowner is going to want every amp he can get. 

Since you are already doing a panel change, breaking the panel into a main panel and an emergency panel will allow this to happen. A transfer switch (either manual or auto) is inserted between the main and emergency. (You could also use an interlocked breaker in the emergency panel.) The genny is connected to the transfer switch. The solar line side tap goes in the emergency panel (or you could backfeed the bottom breaker in the emergency panel). Move as many amps as the genny can handle reliably into the emergency panel.


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## gpop (May 14, 2018)

Coppersmith said:


> I haven't drawn this out to verify but I think you can (and would want to) have the solar system working when the generator is operating. In a power outage, the homeowner is going to want every amp he can get.
> 
> Since you are already doing a panel change, breaking the panel into a main panel and an emergency panel will allow this to happen. A transfer switch (either manual or auto) is inserted between the main and emergency. (You could also use an interlocked breaker in the emergency panel.) The genny is connected to the transfer switch. The solar line side tap goes in the emergency panel (or you could backfeed the bottom breaker in the emergency panel). Move as many amps as the genny can handle reliably into the emergency panel.


Solar and generator do not play nice together and most solar controllers will detect the generator feed and automatically disconnect.


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## Coppersmith (Aug 11, 2017)

gpop said:


> Solar and generator do not play nice together and most solar controllers will detect the generator feed and automatically disconnect.


Ok, I did some research and I think you are correct that the generator and solar system can't work together, but not for the reason you stated. The reason is that the solar system, once it senses the 60 HZ power from the generator, will start operating and will possibly backfeed power into the generator which may damage it. 

I saw this said on a couple of PV related sites, but more research is required to see if it is really true.


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## 460 Delta (May 9, 2018)

gpop said:


> Solar and generator do not play nice together and most solar controllers will detect the generator feed and automatically disconnect.


I assume this is because of frequency? Most smaller generators start about 62 cycles unloaded and sag to 58 cycles at 100% load.


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## kb1jb1 (Nov 11, 2017)

As someone said before, do not concern yourself too much with what others say. I just priced out a very similar job at $1,950.00 plus the permit and inspection fees and I do not know if I got the job. My material cost is about $700.00 dollars and I will gladly work for $1,200. for a days labor. My overhead is low and all my equipment and trucks are paid off. Before the Covid mess I heard people at the supply house bragging that would not leave home for less than $2,500.00. I tried to break the 2,000.00 ceiling but was loosing jobs which leads me to believe some people were rectally conversing. Yes, some electricians do get the big bucks but they advertise heavily and have nice new trucks. I found it interesting that some homeowners knew exactly how much the materials cost. So examine your overhead, expenses, clientele, image in the community. You do not want to be over charging someones grandma and be accused of ripping her off. You also don't need to make it a hobby.


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## yankeejoe1141 (Jul 26, 2013)

Coppersmith said:


> gpop said:
> 
> 
> > Solar and generator do not play nice together and most solar controllers will detect the generator feed and automatically disconnect.
> ...


I thought the system was designed so that the solar backfeeds the utility grid and therefore should only work in conjunction with the utility power. That’s why it’s line side tapped before the main. But I still don’t understand exactly how they sync up and work together. 

Although I agree it would be nice to have the solar power available during an outage, seems like somethings wrong with that picture....all those panels on the roof and no power in the house.


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## yankeejoe1141 (Jul 26, 2013)

kb1jb1 said:


> As someone said before, do not concern yourself too much with what others say. I just priced out a very similar job at $1,950.00 plus the permit and inspection fees and I do not know if I got the job. My material cost is about $700.00 dollars and I will gladly work for $1,200. for a days labor. My overhead is low and all my equipment and trucks are paid off. Before the Covid mess I heard people at the supply house bragging that would not leave home for less than $2,500.00. I tried to break the 2,000.00 ceiling but was loosing jobs which leads me to believe some people were rectally conversing. Yes, some electricians do get the big bucks but they advertise heavily and have nice new trucks. I found it interesting that some homeowners knew exactly how much the materials cost. So examine your overhead, expenses, clientele, image in the community. You do not want to be over charging someones grandma and be accused of ripping her off. You also don't need to make it a hobby.


Your numbers are almost exactly as mine were, but after CTshockhazzard’s comment I felt like I was leaving money on the table so I upped them and still got the job. My situation may be different than other electrician’s out there but the customer is still getting the same from either of us - a licensed and insured electrical contractor to do the job - so I feel like I should get as much as the other guys do, or at least be in the same ballpark.


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## yankeejoe1141 (Jul 26, 2013)

kb1jb1 said:


> As someone said before, do not concern yourself too much with what others say. I just priced out a very similar job at $1,950.00 plus the permit and inspection fees and I do not know if I got the job. My material cost is about $700.00 dollars and I will gladly work for $1,200. for a days labor. My overhead is low and all my equipment and trucks are paid off. Before the Covid mess I heard people at the supply house bragging that would not leave home for less than $2,500.00. I tried to break the 2,000.00 ceiling but was loosing jobs which leads me to believe some people were rectally conversing. Yes, some electricians do get the big bucks but they advertise heavily and have nice new trucks. I found it interesting that some homeowners knew exactly how much the materials cost. So examine your overhead, expenses, clientele, image in the community. You do not want to be over charging someones grandma and be accused of ripping her off. You also don't need to make it a hobby.


And good luck getting that job, I’d be interested to see if anyone beats you out and does it for cheaper.


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## jw0445 (Oct 9, 2009)

joedawson79 said:


> Thanks, and thanks for your advise about the price too. I reprinted my quote with an additional $500 on it, but before I went to see the guy he called me and we agreed on a price over the phone, $400 more than I was going to originally ask for.


And did you get the work?


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## yankeejoe1141 (Jul 26, 2013)

jw0445 said:


> And did you get the work?


Yes, I'll be doing the job for him in two weeks.


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## gpop (May 14, 2018)

joedawson79 said:


> I thought the system was designed so that the solar backfeeds the utility grid and therefore should only work in conjunction with the utility power. That’s why it’s line side tapped before the main. But I still don’t understand exactly how they sync up and work together.
> 
> Although I agree it would be nice to have the solar power available during an outage, seems like somethings wrong with that picture....all those panels on the roof and no power in the house.


Power has to be used as its made. Consumers try to drag the grid down from 60 hertz. Power company's try to boost the grid up to 60 hertz.

In a home you would need a minimum load that exceeds the max output of the solar panels or the generator will turn in to a motor. Also the voltage regulators will probably get into a fight so its just asking for trouble. 

Add a bunch of batteries and bring the generator in to a solar controller that can convert it to dc before inverting it back to AC. 
Then add a timing signal and you will end up with a very expensive off grid solution that saves you a few dollars as long as the power cut is during day light hours.


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## just the cowboy (Sep 4, 2013)

canbug said:


> then add 10-20 percent for the " what did I forget clause".
> Tim.


Do this on any new type job, and put that money away as " Oh [email protected] I forgot to put this in money" That way you may never lose on a job, this fund covers you. 
If you never use it, it becomes retirement fund.

Cowboy


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## Coppersmith (Aug 11, 2017)

joedawson79 said:


> I thought the system was designed so that the solar backfeeds the utility grid and therefore should only work in conjunction with the utility power. That’s why it’s line side tapped before the main.


Solar systems insert power into your electrical panel. That power is used by your local branch circuits. If your local circuits are not using it all, the excess flows back into the utility grid.

The solar system is designed to shut off if it doesn't sense utility power. This is just a safety measure to keep line crews safe in case of an outage. The solar system doesn't care if you have utility power or not otherwise. 

The solar system also can't tell the difference between utility power and power coming from your local generator.

Not all solar systems are line side tapped. A backfed breaker can also be used but it requires the panel to have sufficient ampacity on its buss bars and space for the breaker. Breakers are easier and will usually be used if possible. 




joedawson79 said:


> But I still don’t understand exactly how they sync up and work together.


The inverter changes the DC coming from the solar panels into AC at 60 hz. It does this electronically so it's simply a matter of tracking the sine wave of the utility power and outputting a sine wave that matches it's timing.

If you really want to blow your mind consider that all the giant generators on a power grid are also in sync. When a generator comes online it is not connected to the grid at first. First it is brought up to speed (60 hz here in America) then the sine wave of the generator is compared with that of the power on the grid. The speed the generator is tweaked (changed minutely) until the sine waves are in alignment. Then the big disconnect is closed and the generator is connected to the grid.

Once connected to the power grid, the generator is locked into the sine wave. If the generator stops producing power for some reason like a mechanical failure of its prime mover, it will be backfed with power from the grid and start to act like a motor i.e. it will be pulled along at 60 hz until it is disconnected from the grid for repair. If the rotor is slowed down due to mechanical failure, bad things will happen.


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## kb1jb1 (Nov 11, 2017)

joedawson79 said:


> And good luck getting that job, I’d be interested to see if anyone beats you out and does it for cheaper.


The job is about 1/2 mile from my office so I will see how it pans out. I haven't heard back from the homeowner yet. Next time I will bump up my price and see what happens. Some contractors can afford to wait for the higher prices, I cannot. I lost two large jobs due to Covid cancellations so I have to take what I can right now.


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## yankeejoe1141 (Jul 26, 2013)

Does anyone know a good place to order warning labels for the meter and panel stating there are three sources of power onsite? (Utility, PV, and portable generator). I know the inspector for that town always looks for the appropriate warning label and I didn’t see any great options when I did a quick google search.


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## canbug (Dec 31, 2015)

Get some stickers made up that also have your company name and number.
Spend the extra couple of bucks to get a UV and weather resistant ones. They will last years and help drive business.

Tim


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## yankeejoe1141 (Jul 26, 2013)

canbug said:


> Get some stickers made up that also have your company name and number.
> Spend the extra couple of bucks to get a UV and weather resistant ones. They will last years and help drive business.
> 
> Tim


That’s a great tip, thanks!


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## cuba_pete (Dec 8, 2011)

Reading through these posts and not having done a solar system myself, I'm thinking that protecting the stupids is working against us.

The solar system on my house would actually be part of the grid as it feeds, on bright sunny days, the system when I use only a little to none...the excess goes to the grid.

Now, when the grid goes down so does my bright sunny day backfeed so as to prevent powering the grid during repairs...great. But my solar doesn't feed me during that outage and now I need a generator to keep my freezer working instead of using my battery bank?

Am I interpreting this correctly?

Why wouldn't we design a smarter control system to lockout the grid and still use solar without needing the generator, say at night, with no solar or battery storage?

I understand the frequency shifting with the load (and the source)...but a smarter system should be in design by now.


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## gpop (May 14, 2018)

cuba_pete said:


> Reading through these posts and not having done a solar system myself, I'm thinking that protecting the stupids is working against us.
> 
> The solar system on my house would actually be part of the grid as it feeds, on bright sunny days, the system when I use only a little to none...the excess goes to the grid.
> 
> ...


Most solar set-ups do not have expensive batteries. If you have a battery set-up you can use solar during a power outage.


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## cuba_pete (Dec 8, 2011)

Hmmm...that makes sense. I guess I was assuming there was a battery setup there, like boondocking in an RV to ride through the passing clouds.


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## CTshockhazard (Aug 28, 2009)

joedawson79 said:


> Does anyone know a good place to order warning labels for the meter and panel stating there are three sources of power onsite? (Utility, PV, and portable generator). I know the inspector for that town always looks for the appropriate warning label and I didn’t see any great options when I did a quick google search.



I order mine online here:
https://www.myengravedsign.com/


Oh, and don't forget the extra one at the meter.


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## yankeejoe1141 (Jul 26, 2013)

CTshockhazard said:


> I order mine online here:
> https://www.myengravedsign.com/
> 
> 
> Oh, and don't forget the extra one at the meter.


That's awesome, much better looking than a generic sticker!


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