Transformer seconday disconnect -'hook switch'?

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ces

ces

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Northern California, USA
A contractor has asked me to engineer/detail a transformer mounted up high against the ceiling in a parking structure, with a hook-switch secondary disconnect.
My concern is 1) I thought code says no operators above 6'-6" and 2) I've only seen these used by electric utility companies for example on service poles.
If anyone is familiar with this I'd sure appreciate your comments
 
switch

switch

unless a platform with proper working clearance is provided, it would seem to be a violation of 404.8
 
Exception 3

Exception 3

read it. was assuming (bad) this was the transformer OCP switch also and not "isolation"......don't recall ever seeing an isolation swith on a transformer (in this type application).
that said, you are correct,of course, if it meets ex 3
 
iwire said:
What is an isolating switch?

The NEC uses 'disconnect' 8 billion times,:wink: it seems odd to me that they would not say it this time.
Click to expand...

That is odd.
Switch, Isolating
...it is intended to be operated only AFTER the circuit has been opened by some other means.

Well, if the disco was readily accessible you could still poke at your isolation switch with a stick:grin:
 
I don't have the Square D catalog handy, but I thought there was an adder for all their disco's that you could pick a hook operable disconnect handle? Most buss plugs are certainly this way.
 
I spoke to Square D in Sacramento -the rep/engineer I spoke to said he has not heard of a hook switch. I'm not seeing it in the latest digest either.
Fortunately it has since been agreed to mount the disconnect switch handles at 6'-6".
Thanks.
 
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