Arc Flash Study - FPE and GTE Sylvania Breakers

[OCPD]

Hello,

I am working on arc lash study where they have several old breakers Federal Pacific and GTE Sylvania breakers. I am using SKM for the analysis and for some of them I was able to find the trip curves.

1. As per SKM FPE type NM 600A breaker has an adjustable instantaneous setting. But looking at the breaker I don't see an adjustable dial in front?
2. Does anyone have Zinsco/GTE Sylvania QB breaker trip curves?

 

[wbdvt]

EasyPower also shows adj Inst trip from 5-10X. Can you post a pic of the breaker?

For the Zinsco breaker, what is the size and voltage? You may have to use a generic breaker curve.

 

[OCPD]

EasyPower also shows adj Inst trip from 5-10X. Can you post a pic of the breaker?

For the Zinsco breaker, what is the size and voltage? You may have to use a generic breaker curve.

Uploaded the image. The Images (8082 and 8083) are taken on site. The third one is what I found online.

For Zinsco brekaer the size is mostly 20A/1pole for branch breakers and the main is 100A/3P and a 50A/3P type QB

 

[wbdvt]

I can't tell from the photo but I have seen some breakers where the phenolic cover on the load side has a couple screws to remove and under that cover are the adjustable instantaneous units.

For the Zinsco breakers I would use generic curves but since they are single phase loads (unless ganged together), they can most likely be considered <1.2 cal/cm2 as IEEE 1584 equations are only valid for 3 phase. The 100A breaker sounds like it is the main breaker in that panel and would be ignored for the incident energy calculation for that panel.

I think you could use a generic curve for the 50A breaker also