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Multiple sources/circuits in one cable- allowed?

Multiple sources/circuits in one cable- allowed?

Multiple sources/circuits in one cable- allowed?

(OP)
Is it allowed to use a multi-conductor cable using 2 wires for Circuit A: 208V exhaust fan originating from a contactor in a panel, and also use 2 more wires of the same cable for a 120V line voltage thermostat that goes back to the same contactor control circuit? The thermostat switches the coil of the contactor, the 208V powers the fan.

Is that allowed by code? (Specifically CEC rather than NEC, but I’d imagine they both say the same thing about this)

RE: Multiple sources/circuits in one cable- allowed?

(OP)
I do see this....

14-414 Connection to different circuits
(1) Where electrical equipment is supplied by two or more different transformers or other different sources of
voltage, then
(a) a single disconnecting means that will effectively isolate all ungrounded conductors supplying the
equipment shall be provided integral with or adjacent to the equipment; or
(b) each supply circuit shall be provided with a disconnecting means integral with or adjacent to the
equipment, and the disconnecting means shall be grouped together.
(2) Notwithstanding Subrule (1), disconnecting means integral with or adjacent to equipment need not be
provided for control circuits originating beyond the equipment and not exceeding 150 volts-to-ground,
provided that all associated bare live parts are protected against inadvertent contact by means of barriers.
(3) Where multiple disconnecting means as in Subrule (1)(b) are provided, suitable warning signs shall be
placed on or adjacent to each disconnecting means so that all of the disconnecting means must be opened
to ensure complete de-energization of the equipment.
(4) Where barriers are used as required in Subrule (2), a suitable warning sign shall be placed on or adjacent
to the equipment, or on the barriers, indicating that there is more than one source of supply to the
equipment.

RE: Multiple sources/circuits in one cable- allowed?

Install a junction box ahead of the local motor disconnect and break out the thermostat wiring from the junction box. You may then use a standard disconnect for the motor.
Label the junction box to indicate more than one source of supply and indicate the source for LOTO. (Lock-Out, Tag-Out.)

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Multiple sources/circuits in one cable- allowed?

Are both circuits de-energized when you turn-off power to the panel?

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