Torque Spec's needed for Zinsco 400A. single phase Fused Switch

[Randall Engineering]

I am in need of the bus connection and conductor lug torque settings for a Zinsco #QSF6032 Fused Switch. It is in a 400A. Single phase 120/240v. Main service. It was replaced today, and the inspector needs to witness the torque sets.

 

[Jraef]

I am in need of the bus connection and conductor lug torque settings for a Zinsco #QSF6032 Fused Switch. It is in a 400A. Single phase 120/240v. Main service. It was replaced today, and the inspector needs to witness the torque sets.

Replaced? Zinsco hasn't been around since the 70s, and even it's successor, GTE/Sylvania (which MIGHT have still sold a "Zinsco" branded switch), disappeared over 30 years ago. So you didn't replace it with anything new and you are not likely to find anyone with data sheets on old obsolete equipment from defunct manufacturers now...

 

[kwired]

Slip a 10 foot piece of pipe over your ratched/wrench and pull from the far end of it. When the lug breaks you went too far, back it up slightly

 

[Jraef]

Slip a 10 foot piece of pipe over your ratched/wrench and pull from the far end of it. When the lug breaks you went too far, back it up slightly

We laugh, but that's not so far from the truth... :slaphead:

Back to seriousness though, you (Randall Engineering) MIGHT take a look at the lugs used by Zinsco. If they were something made by someone else like Ilsco or Burndy, chances are those same lugs are still in production now and would have torque specs on them. You might get lucky, you never know!

 

[Santa49]

santa49

santa49

We laugh, but that's not so far from the truth... :slaphead:

Back to seriousness though, you (Randall Engineering) MIGHT take a look at the lugs used by Zinsco. If they were something made by someone else like Ilsco or Burndy, chances are those same lugs are still in production now and would have torque specs on them. You might get lucky, you never know!

Why couldn't you use the recommended tightening torque suggested in the Informative Annex I in the 2014 NEC?

 

[kwired]

Why couldn't you use the recommended tightening torque suggested in the Informative Annex I in the 2014 NEC?

When all else fails that is a good place to go.

 

[jumper]

We laugh, but that's not so far from the truth... :slaphead:

Yep, Brian John once posted some survey/test on torqued terminations and IIRC the larger majority by far was over torqued rather than under.