coolbreeze
Member
Commercial building that need 34 outlets for engine block heaters (1200w each @ 120v). 200A 120/208y 3p system to feed circuits from.
My questions are the following:
1. Are these considered continuous loads? (it's if they are hooked up for 3 hours or more right?) ? so, could you put on a timer and/or temperature switch controlling a relay to stay under the 3hrs which would also save lots of electricity?
2. Total load calculation for the 34 loads at 1200w each (how this is addressed/calculated under the 120/208y 3ph system). My understanding is that the 200a 120/208y 3p system can handle 71,968 watts of load. Therefore, the 34 loads with a total rating of 40,800 watts can be supplied with this loadcenter, even though, I have 34 loads at 10a each or 340A of load @ 120v.
3. Can a 30A protected circuit be used supplying 2 loads together (each load on a GFCI receptacle)? Assuming I am using #10 copper
4. Can a 20A GFCI receptacle be used when using a 30A overcurrent device supplying 2-20A GFCI (each with a so-called dedicated 1200w load for a truck engine block heater)?
At the receptacle, each driver will use an extension cord to plug into his truck heater
Thanks for any input.
My questions are the following:
1. Are these considered continuous loads? (it's if they are hooked up for 3 hours or more right?) ? so, could you put on a timer and/or temperature switch controlling a relay to stay under the 3hrs which would also save lots of electricity?
2. Total load calculation for the 34 loads at 1200w each (how this is addressed/calculated under the 120/208y 3ph system). My understanding is that the 200a 120/208y 3p system can handle 71,968 watts of load. Therefore, the 34 loads with a total rating of 40,800 watts can be supplied with this loadcenter, even though, I have 34 loads at 10a each or 340A of load @ 120v.
3. Can a 30A protected circuit be used supplying 2 loads together (each load on a GFCI receptacle)? Assuming I am using #10 copper
4. Can a 20A GFCI receptacle be used when using a 30A overcurrent device supplying 2-20A GFCI (each with a so-called dedicated 1200w load for a truck engine block heater)?
At the receptacle, each driver will use an extension cord to plug into his truck heater
Thanks for any input.
