SPDs in Main Disco, Meter, or ATS

[Doc13067]

We are on the 2017 NEC so surge protection is not a requirement in my state. But because of recent surge issues with mini splits, I am trying to get all of my clients surge protected. I am unfortunately a Generac dealer so a few of my clients have transfer switches as the main service disconnect. So if I were to put a main breaker panel mounted SPD in what used to be the main panel it would exclude the ATS and generator upstream of it. So I am looking at how to get the SPD in the ATS or meter socket. I am thinking of removing lug mount nuts and putting eyelet crimp connectors on the posts under the nuts either in a meter socket or on the bars in the ATS. Just out of curiosity do any of you have a method for getting surge protection in front of a resi auto standby generator? For those of you who have to put outside main disco if you only had a main breaker enclosure with no additional spaces, you would be faced with the same issue. I don’t want to double the SPD wires with the service or feeder wires. I see no value in putting number 12s next to 4/0 under the same lug.

I asked about something like this once before and I got some bot telling me to “stop! and call an electrician!” and giving me a classroom lecture about how these things work lol remember that?

 

[TwistLock]

Regarding your code cycle and SPD's not being a requirement, I would recommend reading the HVAC equip manual first because many mfgs now require SPD protection for warranty.

 

[Doc13067]

Regarding your code cycle and SPD's not being a requirement, I would recommend reading the HVAC equip manual first because many mfgs now require SPD protection for warranty.

Yeah, we are putting it in every mini split disconnect and I am trying to get it at the beginning of every service. But the best thing I can come up with is what I mentioned.

 

[Doc13067]

 

[Doc13067]

So this is what I came up with. By putting these ring terminals over the lug posts I can get the SPD in front of both panels in a 400A Service as well as in front of the automatic transfer switch. Now the generator is protected from surges as well as the home. I ran #6 copper from each leg to a straight bug and connected the SPD to the straight bugs. Now if it needs to be changed in the future all we need to do is shut the service down and connect a new SPD to the set screw connectors. Best method I could come up with.