a field built 120 ft by 16ft walk in box inside a warehouse that has 4 compressor on the roof of the building & 4 inside units, a 50 amp branch circuit is run to the roof top unit and from the roof top unit 3 circuits 1 480 volt fan circuit, 1 480 volt defrost heater circuit & 1 208 volt control circuit is run to the inside unit, the question came up about disconnects at the inside units (3 on each?), 440.3 (B) seems to refer you to other code sections, would a breaker lockout comply for the inside units or would disconnects be required at each inside unit, thanks in advance
walkin box disconnect
- Thread starter mpd
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In order to comply with 430.102(B) the coolers I inspect are all required to have an "insight" disconnecting means for the motors.
As best I can tell, the defrost heaters can have a disconnect out of sight if lockable.
As best I can tell, the defrost heaters can have a disconnect out of sight if lockable.
- Location
- Massachusetts
I deal with them all the time but I often wonder if we are doing it right.
It seems that what Gus said is how it is interrupted here. We provide an switch inside the cooler for the fans. But not for defrost heaters or control circuits.
Personally I don't even think the fans require an additional disconnecting means as the fans all plug into the enclosure.
If these fans do require an additional in sight disconnecting means than I have to ask where are we locating the additional disconnecting means for the fans that are in the cases out on the sales floor.
It seems that what Gus said is how it is interrupted here. We provide an switch inside the cooler for the fans. But not for defrost heaters or control circuits.
Personally I don't even think the fans require an additional disconnecting means as the fans all plug into the enclosure.
If these fans do require an additional in sight disconnecting means than I have to ask where are we locating the additional disconnecting means for the fans that are in the cases out on the sales floor.
thank you for the replies, the electrician installed a disconnect for the fans, but he is worried about the other 2 circuits feeding the unit and the possibility of somebody thinking that switch disconnects all power to the unit. the refrigeration contractor does not want any disconnect switches for the inside units. my thought was proper labeling and a breaker lockout for the inside units if the inside units could be considered as an appliance. any other input would be great
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