62-116 Demand factors for service conductors and feeders
(1) Where service conductors or feeders are used solely for the supply of energy to heating equipment, they
shall have an ampacity not less than the sum of the current ratings of all the equipment they supply.
(2) Notwithstanding Subrule (1), where a heating installation in a building for residential occupancy is
provided with automatic thermostatic control devices in each room or heated area, the ampacity of service
conductors or feeders supplying heating equipment only shall be based on the following:
(a) the first 10 kW of connected heating load at 100% demand factor; plus
(b) the balance of the connected heating load at 75% demand factor.
(3) Where service conductors or feeders are used to supply an electric thermal storage heating system, duct
heater, or an electric furnace, the connected heating load shall be calculated at 100% demand factor.
(4) Where service conductors or feeders supply a combined load of heating and other equipment, they shall
have an ampacity consisting of the following:
(a) in the case of buildings for residential occupancy, the sum of the heating load as computed by
Subrules (2) and (3) plus the combined loads of other equipment with demand factors as applicable
in Section 8; or
(b) in the case of other occupancies, 75% of the total connected heating load plus the combined loads
of the other equipment with demand factors as applicable in Section 8 for the type of occupancy.
(5) Notwithstanding Subrule (4)(b), where the combined load with applicable demand factors of other than
heating equipment is less than 25% of the connected heating load on a service or feeder, no demand factor
shall be applicable to the heating portion of the load.shall have an ampacity not less than the sum of the current ratings of all the equipment they supply.
(2) Notwithstanding Subrule (1), where a heating installation in a building for residential occupancy is
provided with automatic thermostatic control devices in each room or heated area, the ampacity of service
conductors or feeders supplying heating equipment only shall be based on the following:
(a) the first 10 kW of connected heating load at 100% demand factor; plus
(b) the balance of the connected heating load at 75% demand factor.
(3) Where service conductors or feeders are used to supply an electric thermal storage heating system, duct
heater, or an electric furnace, the connected heating load shall be calculated at 100% demand factor.
(4) Where service conductors or feeders supply a combined load of heating and other equipment, they shall
have an ampacity consisting of the following:
(a) in the case of buildings for residential occupancy, the sum of the heating load as computed by
Subrules (2) and (3) plus the combined loads of other equipment with demand factors as applicable
in Section 8; or
(b) in the case of other occupancies, 75% of the total connected heating load plus the combined loads
of the other equipment with demand factors as applicable in Section 8 for the type of occupancy.
(5) Notwithstanding Subrule (4)(b), where the combined load with applicable demand factors of other than
heating equipment is less than 25% of the connected heating load on a service or feeder, no demand factor
