Heating Load Conductor Sizing
#1
05-12-15, 03:40 PM
Heating Load Conductor Sizing
Hello,
I have two heating loads within 40' of my 277/480 panelboard. One is 16.6a and the other is 23.5a. They can both be circuited to a 3-pole 480 volt circuit. They are continuous load.
I have sized the conductors by (16.6+23.5)*1.25 to get 50.1 or #6 AWG.
Is this correct? Do I need #6 throughout the circuit?
Tripper
I have two heating loads within 40' of my 277/480 panelboard. One is 16.6a and the other is 23.5a. They can both be circuited to a 3-pole 480 volt circuit. They are continuous load.
I have sized the conductors by (16.6+23.5)*1.25 to get 50.1 or #6 AWG.
Is this correct? Do I need #6 throughout the circuit?
Tripper
#2
05-12-15, 03:49 PM
Group Moderator
Will you be running an additional breaker, for protection, at each heating unit ?
You can't connect two units to a single breaker as the breaker size is too large to correctly protect each heater.
You can't connect two units to a single breaker as the breaker size is too large to correctly protect each heater.
Last edited by PJmax; 05-12-15 at 05:02 PM.
#4
05-16-15, 01:36 PM
Member
Ultimately, Joe is right.
Is this a commercial or residential (480V acreage shop?) setting though?
CEC states you can put multiple heaters on a circuit so long as they do not exceed 60A commercially (unless the loads are balanced, then you may exceed in a 3 phase system) and 30A in a residential setting. Maybe the NEC has the opposite opinion on this subject but I can't see it being much different.
CEC has crazy sizing rules for heating circuits so someone versed in the NEC should help you with that.
Is this a commercial or residential (480V acreage shop?) setting though?
CEC states you can put multiple heaters on a circuit so long as they do not exceed 60A commercially (unless the loads are balanced, then you may exceed in a 3 phase system) and 30A in a residential setting. Maybe the NEC has the opposite opinion on this subject but I can't see it being much different.
CEC has crazy sizing rules for heating circuits so someone versed in the NEC should help you with that.
