Cable clamp, not fitting knockout on breaker box....

Old 02-16-17, 05:31 PM
Thread Starter
Join Date: Mar 2016
Location: USA
Posts: 41
Likes: 0
Received 0 Likes on 0 Posts
Cable clamp, not fitting knockout on breaker box....

Ok guys, I am driving myself insane here! I am installing a brand new square d 100amp breaker box 22 spaces I believe. So I am using a 2/2/2/4 cable and so I got the 1 1/4" clamp. Okay punch the knockout, okay to small...okay take out another ring...okay to big now...okay buy a 1 1/2" clamp now...knockout hole to small okay another big now...

Get the picture?

So I have an exactly 2" hole in the knock out. I go and get a 2" two big for the box even the last ring...

I figured okay, I goofed? I thought I'll move the service line entrance from the side to the top and plug that knockout...

I measure before....non of the knockouts...will punch out to allow the threaded end of a 1 1/4in cable clamp threw the box...

What am I doing wrong???

I admit I am a noob, but every fuse box and breaker box I look at all have just a clamp holding the service line to the box and no odd adapters....

I bought a reduction washer, to attempt to get the 1 1/4in clamp to fit into the to large 2" knockout I made and they won't even slide over the threaded end of the clamp...
Old 02-16-17, 07:06 PM
Tolyn Ironhand's Avatar
Group Moderator
Join Date: Nov 2007
Location: United States
Posts: 15,030
Received 628 Likes on 537 Posts
Please post a picture, or post a link, of the fitting you are trying to use. Something does not sound right.
Old 02-16-17, 07:34 PM
ray2047's Avatar
Join Date: Mar 2006
Location: USA
Posts: 33,575
Likes: 0
Received 15 Likes on 13 Posts
Also what is the outside diameter of the 1" cable clamp you have?
Old 02-16-17, 07:54 PM
Thread Starter
Join Date: Mar 2016
Location: USA
Posts: 41
Likes: 0
Received 0 Likes on 0 Posts
Maybe I goofed? That is all I can think of...

This is the knockout that is 2"
Name:  20170216_203915.jpg
Views: 2126
Size:  20.0 KB

This is it prior to knocking out(identical one on reverse)
Name:  20170216_203940.jpg
Views: 1843
Size:  14.4 KB

It looks like it will fit in a knock out on the top left corner, fingers crossed!
Name:  20170216_204038.jpg
Views: 2271
Size:  22.2 KB

I suppose I will just cap the other knockout, its odd because the 1 1/2in I got first would not fit or screw in the proper knockout and the 2nd ring removed it just fell threw..

Here is the connector now went back to 1 1/4..measurement of threaded side just shy of 1 3/4"...
Name:  20170216_204159.jpg
Views: 2173
Size:  37.6 KB
Old 02-16-17, 08:12 PM
Join Date: May 2015
Location: USA
Posts: 3,283
Received 66 Likes on 51 Posts
Not sure why it won't fit a standard knockout.

Get yourself one of these in appropriate size for cable:

Name:  Clamp connector.jpg
Views: 2695
Size:  17.3 KB

They are called two piece clamp connectors and don't require a lock nut.
The two right angle tabs go inside the box, and the edges of the clamp part prevent it from going into the box. Hole size is not very critical.
Old 02-16-17, 08:16 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Jersey
Posts: 70,987
Received 3,176 Likes on 2,852 Posts
I agree with the others. The sizes should be standard. Some of those multisize KO's can be iffy. (electricians carry doughnuts just for those reasons)

Name:  panel.jpg
Views: 3866
Size:  16.0 KB
I think that's how they go.... normally.
Old 02-16-17, 08:51 PM
Thread Starter
Join Date: Mar 2016
Location: USA
Posts: 41
Likes: 0
Received 0 Likes on 0 Posts
ah! Didn't think about those two piece ones!

The hardware store is going to get sick of me returning clamps lol He already said it must be quite the project, third day in a row you've been in here...

I said...hunny...I will be in here every day for the next twenty years lol

Thread Tools
Search this Thread
Ask a Question
Question Title:
Your question will be posted in: