DISCONNECT OR NOT

[pristava]

We have (1) 10HP, 575 Volts 3p motor and
(2) 70kW, 600 Volts 3p heater
provided to be connected to one circuit from 600V A.C. panel.
Each load ( heater or motor)is delivered with its own fuse protection.
Is it necessary to provide diconnect (or fuse switch)between these fuses and main C.B.
I mean two disconnects - one for heater plus one for motor.
I am in Canada
Thanks.

 

[mpparent]

I would say as long as your equipment has a disconnect on it, you should be fine (preferrably lockable).

Mike

 

[digitrex]

Where is the motor overload protection relay? If it is located at the main CB(which feeds to both motor and heater), I don't think it is a correct location.
If you don't have overload relay but you can afford to have the motor burnt-out when it gets overloaded, then it is not a concern.

The question of disconnect switches for motor and heater depends on whether you need to isolate only one of the two. If you always have to shutdown both of them, the main CB (padlockable) should be sufficient.

 

[rbulsara]

What is the application? This sounds like a AC unit with a reheat coil? Is this an assembly??

 

[candu6]

Section 28-600 of the Canadian Electrical Code covers disconnecting means for motors. Take a read.
I think that 28-604 (3) applies and you need a disconnect within sight and 3 meters of the equipment.