SPD Connections

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augie47

augie47

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Type 1 SPDs are allowed to be connected on the line side or load side of service disconnecting means, however, the line/load lugs are seldom if ever rated to accommodate the service/feeder conductors and the SPD smaller (#10) conductor.
This leads to a violation of 110.14(A),
How are you addressing this in the field ??

(I keep finding the #10 SPD Cu conductor simply stuck behind the 4/0 AL conductor))
 
This has been a problem for years and is getting worse now that SPD are required. A real problem when you just have a meter and a main breaker. The only real solution is to install the SPD at the first panel and use a breaker.
 
I have always just put them on a breaker. connecting them to the service conductors just seems like a hassle, I am not even sure there is a connector that will do those two drastically different sizes!
 
Honestly this is why I just passed up a Type 1. I just bought two FS140 SSD https://www.amazon.com/Siemens-FS140-Whole-House-Protection/dp/B013WINMK6 and the instructions say to use a 2 pole 20. OK SO now my dilemma is the location on a 400 amp service with 2 -200a panels. They are next to each other. One can go in the side of one panel the other cant. It has to go top or bottom and the distance from the 1st breaker is about equal from top and bottom. So no perfect solution. It makes me think I should have gotten the type 1 and just put it under the lugs. Cant win. A type one at the meter base should be more effective, but it is a hassle. Another example of how things don't always keep pace with the change.

For every foot of wire = 1 nano second of response time, and 175v are added to clamp voltage as per instructions.
 
Havent seen it done yet, but wouldn’t those insulated piercing type connectors serve the purpose? The kind the PV guys use on a line side tap.
 
Greentagger said:
Havent seen it done yet, but wouldn’t those insulated piercing type connectors serve the purpose? The kind the PV guys use on a line side tap.
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Good point. I was surprised that they do actuallymake one that accepts those wire sizes (4/0-10).
 
It is not impossible to find circuit breaker lugs that have a tapped hole on them. No reason you couldn't use that hole for a screw to connect a ring terminal to the lug.

Not available for all terminal lugs admittedly.
 
There is a type 1 SPD that is UL classified to connect to the back side of the main lug on the line side of the main breaker. It uses a pin/sleeve type of connection. Inspectors don't like it, but it is approved.
 
inspector141 said:
There is a type 1 SPD that is UL classified to connect to the back side of the main lug on the line side of the main breaker. It uses a pin/sleeve type of connection. Inspectors don't like it, but it is approved.
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I seem to recall a post on this. Maybe someone can locate it.
 
I guess so. Ive never fully understood how that works. Seems likes the product receiving the classified item needs to have its listing/instruction amended to allow that other product. Otherwise, it seems like a conflict to me if one thing says you can and another says you cant.
 
electrofelon said:
I guess so. Ive never fully understood how that works. Seems likes the product receiving the classified item needs to have its listing/instruction amended to allow that other product. Otherwise, it seems like a conflict to me if one thing says you can and another says you cant.
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Not really. The listing of all the products used together taken together is what matters not the listing of a single product.
 
FWIE: After the possibility "listing"came into question I contacted UL>
I just heard back from their Senior Regulatory Engineer and he advises there is no SPD listed that would not have to comply with 110.14
 
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