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As im going thru all the panels in 2 bldgs im head sparky for now. Thermal scans for baseline. 1-19 flrs, 1-16 flrs. Ive noticed some interesting things.

 

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Bilge Rat
motors and controls.........
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Square D has made QOB110VH, QOB125VH and QOB150VH breakers for a long time. They are SPENDY!!!! And care must be taken to not install a 3 pole unit in a single phase panel or a 2 pole one in a 3 phase panel; it'll blow up.

I've also seen the QO adapters. The 3 pole one is model#HQO306. It has space for 6 QO breakers, but they cannot exceed 30 amps each.

One bad thing about using QO breakers in an I-line board is the available fault current. I-line is switchgear, and it often has more than 10,000 amps of fault current.

Another thing I haven't seen yet is the adapter installed in a 480 I-line board. It'll fit; imagine closing a 120 volt QO breaker into a 277 bolted fault..........
 
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