The hole of cable lug?

[Jed057]

Any goru,
please advise.any standard mention one or two hole for cable lug,
currently I need to use cable lug for 300 sq.mm at secondary side of transformer 400V. But the transformer busbar provided for 2 hols cable lug, but I can not find it,
I need to convince to our client to use one hole cable lug only, but I do not know which standard should be back up on this.

Crazy Eng.

 

[PHovnanian]

I don't know if there is a standard per se. But I'd rely on the lug manufacturer's installation instructions. If the lug is installed per their instructions, then it is suitable for the job. If it only has one hole, then that's all the manufacturer figured it needed.

The transformer bus bar may have multiple holes to allow for multiple or parallel secondary runs. Is the load that you are feeding close to the transformer's rating? Is the 300 sq.mm conductor (and the applicable lug) sized for this load?

 

[jraef]

That said, often two hole lug patters are needed because they want to avoid the possibility of the lug turning on the pad and decreasing the clearances between live parts. it's a good idea to always use two hole lugs if you have a two hole pad, it might be that way for a reason.

You seriously can't find two hole lugs?
LMGTFY Link

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[rterickson]

300 mm2 works out to approximately 600 kcmil if I'm not mistaken. That is a pretty big cable to try to wrangle with a one-hole lug.

Something like the #11-104 on the attached cut sheet should do nicely.

Link

 

[7anoter4]

600 MCM=300 sqr.mm From Google "600 mcm 2 holes cable lugs"

http://www.greengorillaindustrial.com/Mechanical_Cable_Lug_600_MCM_2_Hole_Mount_p/103-1222.htm

http://www.e-photon.com/Catalog/Two-Hole-Lead-Plated

Burndy YAG39L2NTCLD -

http://www.ebay.com/sch/sis.html?_n...CM 2 hole crimp lug NIB &_itemId=370339470617

Blackburn ATL-6002
and other

 

[Jed057]

Thank you all
jraef, I can find it but delivery time is too long.

 

[Marmite]

It could be that the transformer has been designed to accommodate two sets of LV single cores per phase, rather than a two hole lug.
Regards
Marmite

 

[gattie]

A 2 Hole lug is a far superior fixing of this size cable to transformer termination bars.
Main reasons (as mentioned by other members) is ease of installation & less chance of connection working loose under load)
It is standaed practice in South Africa

 

[asco1]

If there is any movement of the cable, a 1-hole lug may become loose (and then hot) or short to another phase or ground.
Movement can be caused by tension of heavy cable & vibration, magnitizim during a short circuit, or just someone pulling on the cable.
NEMA has developed a standard. (2) 1/2" bolts, 1.75" spacing. Most lug manufacturers supply their lugs with a NEMA hole pattern (in addition to single hole lugs).