It's called a floating breaker....

[Electron_Sam78]

...What was the reason for opening up the cabinet?

Scheduled outage for SD CB replacement at a building it feeds.

 

[Electron_Sam78]

outside tap with So cords -- What was the reason for opening up the cabinet?

The SO feeds a "temp" power pedestal for a large cooling tower.

 

[mbrooke]

The grey dial would probably be a tap changer.

 

[Tony S]

Scheduled outage for SD CB replacement at a building it feeds.

So what will you do about the “floating breaker”?

At 800A nominal a heavy fault current is going to cause magnetic repulsion between conductors. It can and has caused substantial damage.

 

[ggunn]

So what will you do about the “floating breaker”?

At 800A nominal a heavy fault current is going to cause magnetic repulsion between conductors. It can and has caused substantial damage.

Is the OP on the hook for bringing it up to code if he is the one who opened the enclosure and found it?

 

[Electron_Sam78]

So what will you do about the “floating breaker”?

At 800A nominal a heavy fault current is going to cause magnetic repulsion between conductors. It can and has caused substantial damage.

Nothing. The right people know about it and don't seem to care

 

[big john]

The grey dial would probably be a tap changer.

Ayuh. Definitely the secondary terminal compartment of a padmount transformer.