I had a new 480V press come in that has a controller with it (motor starter, overload relay, plc, control transformer). The controller has start/stop buttons and a keyed lock to lock out the control circuit from the control transformer. Since this lockout only locks out the power from the control transformer does this qualify as a controller disconnect even though this does not isolate the 480V branch circuit or is the NEC's intent to have all power sources to the controller off, ie I will have to add a disconnect switch on the 480 line side of the controller within 50 feet?
Hydraulic Press Controller Disconnect
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jumper
Senior Member
- Location
- 3 Hr 2 Min from Winged Horses
I am thinking you need a disconnect.
430.103 Operation. The disconnecting means shall open
all ungrounded supply conductors and shall be designed
so that no pole can be operated independently. The disconnecting
means shall be permitted in the same enclosure
with the controller. The disconnecting means shall
be designed so that it cannot be closed automatically.
430.103 Operation. The disconnecting means shall open
all ungrounded supply conductors and shall be designed
so that no pole can be operated independently. The disconnecting
means shall be permitted in the same enclosure
with the controller. The disconnecting means shall
be designed so that it cannot be closed automatically.
Aleman
Senior Member
- Location
- Southern Ca, USA
I wouldn't consider it safe unless the line is removed from the motor starter. It doesn't have a main disconnect?
If not then you should add one. Some starters have disconnects built in and can be locked out. Or put a local
disconnect somewhere close to your motor.
If not then you should add one. Some starters have disconnects built in and can be locked out. Or put a local
disconnect somewhere close to your motor.
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