ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
ShoutChat Box
Recent Posts
Northern Tool Recalls Powerhorse Generators
by Admin - 02/25/21 09:49 PM
You will never guess
by gfretwell - 02/25/21 07:48 PM
Lock-down Thread
by Bill Addiss - 02/24/21 04:40 PM
New tool
by SMOKEYBOB - 02/15/21 04:59 PM
New in the Gallery:
Facebook follies, bad wiring
FPE in Germany pt.2
Who's Online Now
0 registered members (), 21 guests, and 17 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Crimp vs. Setscrew - 500 MCM CU #162145 04/13/07 06:50 PM
Joined: Jan 2005
Posts: 109
Grover Offline OP
Opinions? Experiences? Old school boss wants setscrew terminations - I favor proper die hydraulic crimp. Application is parallel runs - 1200 A 480 3 phase. Total of 64 terminations.

Square D QED Switchboard provides setscrew lugs for 32 of the terminations - what do do with the rest?

Appreciate input.


Work Gear for Electricians and the Trades
Re: Crimp vs. Setscrew - 500 MCM CU [Re: Grover] #162153 04/13/07 08:28 PM
Joined: Apr 2002
Posts: 7,233
HotLine1 Offline
4 conductors per phase??
or ???
64 terminations; I'm assuming switchboard to padmount xfr? At 4 per phase...16 and 16..

I'm confused. I'm 'old school' too (59), but I'm partial to crimp terminations.

I've done setscrew lugs (factory installed in gear) and crimps at the padmount supplied by me, installed by me. Our utility requires EC's to do secondary terminations at padmounts.


Re: Crimp vs. Setscrew - 500 MCM CU [Re: HotLine1] #162162 04/13/07 10:04 PM
Joined: Jan 2005
Posts: 109
Grover Offline OP
Hotline - sorry to confuse....

4 pipes - A,B,C,N in each - parallel.

Genset ->Switchgear, Switchgear to MCC

Switchgear has setscrew lugs supplied - Square D QED.

My old school guy has apparetly had trouble with failed crimps (wrong die, not enough pressure?). QED ame with setscrew lugs - weakens my arguement.

I've always used crimps with no complaints...


Re: Crimp vs. Setscrew - 500 MCM CU [Re: Grover] #162170 04/14/07 12:38 AM
Joined: Nov 2006
Posts: 348
ITO Offline
What do the specs say, and what type of terminations did you submit on?

101° Rx = + /_\
Re: Crimp vs. Setscrew - 500 MCM CU [Re: ITO] #162192 04/14/07 12:38 PM
Joined: Nov 2000
Posts: 2,148
resqcapt19 Offline
I will normally toss out the manufacture provided set screw connectors and replace them with compression connectors on equipment of that size. We always use a dieless hydraulic crimper so there is no problem with the wrong die or incorrect pressure. For that many terminations I would be using the cordless hydraulic crimper in place of the hand pumped one.

Re: Crimp vs. Setscrew - 500 MCM CU [Re: resqcapt19] #162199 04/14/07 01:05 PM
Joined: May 2003
Posts: 2,876
e57 Offline
Odds are that the manufacturer makes lugs for the purpose. I've seen 6 and 8 hole lugs like that, and four hole are pretty common. If you dig through the SqD catolog I'll bet you find them. Properly torqued they are just as good a connection IMO.

If you crimped them all - what would you be doing for all the connections to the busswork? Does it have bolt patterns for that? Dont 500MCM crimps have 2-bolts per?

Mark Heller
"Well - I oughta....." -Jackie Gleason
Re: Crimp vs. Setscrew - 500 MCM CU [Re: e57] #162211 04/14/07 04:42 PM
Joined: Nov 2000
Posts: 2,148
resqcapt19 Offline
Crimps are made in either single or two hole type. Many of the larger mechanical lugs are two hole with the same pattern as the crimps.
Properly torqued they are just as good a connection IMO.

In my opinion a properly installed mechanical lug is never as good as a properly installed compression lug. Both will do the job, however I believe that the compression are better. The contact pressure on the mechanical lug is not as high and the quality of the installation is more dependent upon the skill of the installer as compared to installing a compression lug with a dieless hydraulic crimp tool. If you cut through the connector and the wire on a compression termination that was installed with a hydraulic crimp tool, it is hard to tell that the wire was stranded. I guess maybe my preference comes from working mostly on industrial projects when crimp connections are often part of the job specifications.



2020 National Electrical Code
2020 National Electrical
Code (NEC)

* * * * * * *

2020 Master Electrician Exam Preparation Combos
2020 NEC Electrician
Exam Prep Combos:
Master / Journeyman


Member Spotlight
Alan Belson
Alan Belson
Mayenne N. France
Posts: 1,803
Joined: March 2005
Show All Member Profiles 
Top Posters(30 Days)
MCosta 3
Popular Topics(Views)
275,386 Are you busy
209,282 Re: Forum
196,579 Need opinion
Powered by UBB.threads™ PHP Forum Software 7.7.3