Eaton CHSPT2ULTRA with 50A breaker

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doru

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I'm installing an Eaton CHSPT2ULTRA a Type 2 SPD. It has 12 wire pigtails.
Eaton specifies use of 50A breaker.
Breaker is a Siemens Q250U and the terminals are for 8 wire.
I can use some short 8 wire to hook it up with wire nuts.
Is that an acceptable solution?
 
A Siemens QSPD would be a better solution.

So far as I can see Eaton Instruction Bulletin IB00414001Y does not say the conductors cannot be spliced. I would probably no use wire nuts. I think a linear splicing method would be preferred.
 
The ones I have used had enough wire to reach a breaker but I never installed it on a 50 amp breaker. Either I missed that or I forgot---gee-- could be either.
 
hmspe said:
A Siemens QSPD would be a better solution.

So far as I can see Eaton Instruction Bulletin IB00414001Y does not say the conductors cannot be spliced. I would probably no use wire nuts. I think a linear splicing method would be preferred.
Click to expand...
Yep.
Typically SPDs do not like right angle bends in their leads and their performance is affected by lead length.
 
I just read the thread thoroughly and just realized I have that same SPD on my own panel. I do have it on a 50A breaker and placed it so the wires were close enough to not have to splice them.
@doru
You can land the #12 on that 50A breaker. You're not trying to protect the conductors with the breaker so normal breaker/conductor sizing does not apply here. You can use a 15A 2-pole but they recommend the 50A to get the full published ratings of the Ultra. The 15A is actually what they recommend for their other model, which is a CHSPT2SURGE.
 
I installed mine right to the side of the 50A breaker on the outside of the panel so wire length is about 9" well whitin Eaton's recommend range of 12.5". The pigtails are 15" so they're long enough.

My issue is with the breaker as 12 wire is way too small for its terminals. That's why trying to splice a very short piece of 8.
Per above advice I can use an aluminum reducer #14-#2 and torque the bolts according to each wire size, shrink tube covered. I can use the heavy wall/underground tubing but I think is overkill for this application.

Is there another way to land the 12 wire on the 50A breaker?
 
doru said:
My issue is with the breaker as 12 wire is way too small for its terminals.
Click to expand...
Aren't your terminals like the ones pictured?
Is it a screw that bottoms out in the lug?
If so, how is the wire too small?
 

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doru said:
I installed mine right to the side of the 50A breaker on the outside of the panel so wire length is about 9" well whitin Eaton's recommend range of 12.5". The pigtails are 15" so they're long enough.

My issue is with the breaker as 12 wire is way too small for its terminals. That's why trying to splice a very short piece of 8.
Per above advice I can use an aluminum reducer #14-#2 and torque the bolts according to each wire size, shrink tube covered. I can use the heavy wall/underground tubing but I think is overkill for this application.

Is there another way to land the 12 wire on the 50A breaker?
Click to expand...
Mine is on a Siemens 50A breaker. I don't understand why you can't use the breaker you have. Are you saying the terminal won't close enough to capture the #12?
 
Yes, they are like in James picture, and yes, not closing enough. For a moment I felt like stupid so I just went to the garage and looked again. Here is the picture with the screw fully in. It does not bottom out as we expected.
1662354207396.png

The added aggravation is that the pigtails are stranded wire. I can easily pull them out of the lug when the screw is fully in.

I tested with a solid 12 wire and it is clamped pretty well by the screw (have not measured the torque, just tightened by feel).
 
If you could strip more of the insulation off, leaving a longer section of the strands, then double the strands over. That might give you enough area to clamp. Again, the wires carry no current except during a surge so they don't have to be torqued.
 
I wondered how can I get the screw to bottom out so I went and compared the 50A and the 15A screws. Here are the pictures...
15A left, 50A right:
1662356904697.png
They do have the same thread and the same head.

Here they are both in the 50A breaker:
1662357076471.png

The 15A screw it is not quite bottoming out but it is close. It is now able to clamp the #12 stranded wire!

Side by side 50A and 15A breakers both using the 15A screw fully in:
1662357466080.png

Because the 50A lug has significant more space than the 15A lug there is more space for the #12 wire to spread out from under the screw. I need to experiment with the given idea of doubling up the wire under the screw.
 
doru said:
Because the 50A lug has significant more space than the 15A lug there is more space for the #12 wire to spread out from under the screw. I need to experiment with the given idea of doubling up the wire under the screw.
Click to expand...
I thought the same thing as @Little Bill about folding the wire. Maybe even strip 2 inches and fold it twice.

You could also buy two 15 amp breakers and use those screws.
 
Strip the #12 wire about an inch, but do not twist the strands yet.

Fold the strands into a tight U, then twist them as a single thicker wire.
 
This is a circuit breaker manufacturing problem. If the 50 amp CB has a minimum #8 conductor size you cannot "legally" use a smaller conductor. If they simply changed the screw they would broaden the wire range to accept smaller than #8 conductors. Might be a listing issue. Given the newer requirements to provide surge protection these manufacturers should be taking a look at their products.

If the surge protector just had #8 conductors there would be no code issue.
 
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