Type 1 SPD used as Type 2

[jbowman88]

If installing a listed Type 1 SPD on the load side of the service disconnect (as a Type 2 ), is the SPD required to have a separate OCPD?

I’m installing a new service disconnect with breaker on the exterior of a building (480Y/277), which then goes through a tap box to an MDP. There will be a sub-meter that connects inside the tap box (no utility meter, primary metered campus). I would like to also put the SPD right next to the tap box, and tie it into the lugs inside, but not sure if I can do that without OCPD, even with the Type 1 SPD…

Maybe somebody can explain to me the advantage of installing an SPD on the line side of the service disconnect? It just makes it a PITA to work on down the road. Also, I’ve seen few (no?) disconnects that have additional lugs or a means to connect the SPD on the line side. How are folks accomplishing this?

Thanks

 

[jim dungar]

As long as you have an OCPD in your service disconnect, you can connect your Type 1 SPD on its load side.

 

[Seven-Delta-FortyOne]

Type 1 does not require an OCPD, regardless of where it’s installed. The only issue would come up with whether or not the lug was rated for more than one conductor. In reality I haven’t seen too many inspectors worry about it.

 

[Genepires]

I have not done an exhaustive research on this but all the type 1 SPD I have seen have been both type 1 and 2.