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Good afternoon gents..
Im building a tap box & MCC cabinet for a customer.. he has a 300kw generator providing the power, which currently has a 600a non fused disco.. this will be feeding a tap box- feeding a mcc with 5 motor starters, each starter is short circuit protected with its own breaker.. (1) 150hp starter, (1) 20hp starter & (3) 10hp starters..
my question is this.. the distance from his existing generator and disco to my tapbox/ mcc is unknown.. is there a code that determines the distance from my equipment to the nearest disco? I would imagine it aint code to have to run 100' to the nearest main disconnect... (if that ends up being the case)..

Also (if I did all my ******* goesintos correctly).. the generator will produce about 450 amps... total FLA of the starters (if all running full load simultaneously) is 249 amps.. If I need to include another means of main disconnect in my gear, would a 400a breaker or disco be sufficient?
 

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Good afternoon gents..
Im building a tap box & MCC cabinet for a customer.. he has a 300kw generator providing the power, which currently has a 600a non fused disco.. this will be feeding a tap box- feeding a mcc with 5 motor starters, each starter is short circuit protected with its own breaker.. (1) 150hp starter, (1) 20hp starter & (3) 10hp starters..
my question is this.. the distance from his existing generator and disco to my tapbox/ mcc is unknown.. is there a code that determines the distance from my equipment to the nearest disco? I would imagine it aint code to have to run 100' to the nearest main disconnect... (if that ends up being the case)..

Also (if I did all my ******* goesintos correctly).. the generator will produce about 450 amps... total FLA of the starters (if all running full load simultaneously) is 249 amps.. If I need to include another means of main disconnect in my gear, would a 400a breaker or disco be sufficient?


IX. Disconnecting Means
430.101 General. Part IX is intended to require disconnecting means capable of disconnecting motors and controllers from the circuit.

430.102 Location.
(A) Controller. An individual disconnecting means shall be provided for each controller and shall disconnect the controller. The disconnecting means shall be located in sight from the controller location.
Exception No. 1:  For motor circuits over 1000 volts, nominal, a controller disconnecting means lockable in accordance with 110.25 shall be permitted to be out of sight of the controller, provided that the controller is marked with a warning label giving the location of the disconnecting means.
Exception No. 2:  A single disconnecting means shall be permitted for a group of coordinated controllers that drive several parts of a single machine or piece of apparatus. The disconnecting means shall be located in sight from the controllers, and both the disconnecting means and the controllers shall be located in sight from the machine or apparatus.
Exception No. 3:  The disconnecting means shall not be required to be in sight from valve actuator motor (VAM) assemblies containing the controller where such a location introduces additional or increased hazards to persons or property and conditions (a) and (b) are met.
(a) 
The valve actuator motor assembly is marked with a warning label giving the location of the disconnecting means.
(b) 
The disconnecting means is lockable in accordance with 110.25.
(B) Motor. A disconnecting means shall be provided for a motor in accordance with (B)(1) or (B)(2).
(1) Separate Motor Disconnect. A disconnecting means for the motor shall be located in sight from the motor location and the driven machinery location.
(2) Controller Disconnect. The controller disconnecting means required in accordance with 430.102(A) shall be permitted to serve as the disconnecting means for the motor if it is in sight from the motor location and the driven machinery location.
Exception to (1) and (2): The disconnecting means for the motor shall not be required under either condition (a) or condition (b), which follow, provided that the controller disconnecting means required in 430.102(A) is lockable in accordance with 110.25.
(a) 
Where such a location of the disconnecting means for the motor is impracticable or introduces additional or increased hazards to persons or property
Informational Note:  Some examples of increased or additional hazards include, but are not limited to, motors rated in excess of 100 hp, multimotor equipment, submersible motors, motors associated with adjustable speed drives, and motors located in hazardous (classified) locations.
(b) 
In industrial installations, with written safety procedures, where conditions of maintenance and supervision ensure that only qualified persons service the equipment

Informational Note:  For information on lockout/tagout procedures, see NFPA 70E-2012, Standard for Electrical Safety in the Workplace.
 
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