Forum Posts

• October 12, 2019 11:15 AM PDT

  in the topic Branch circuit in the forum Electrical Engineering

  Yes, you are allowed.
• October 4, 2019 9:20 PM PDT

  in the topic CB or OCPD rating of the feeder. in the forum Electrical Engineering

  Stacy Littleton said: I'd like to just comment on the CB or OCPD rating of the feeder. The ampacity is determined by the method described, 125% of the anticipated full load. The OCPD then can be selected base on that. For feeders, the standard size value for OCPD can be rounded down from that ampacity rating, not up as required for branch circuits. You are correct the feeder must be sized to have an ampacity at least (minimum) 125% of the load, if it is a continuous load, as stated in 215.2(A)(1)(a). The overcurrent device must also be sized to at least 125% of a continuous load as stated in 215.3. You might be able to round down from the conductor ampacity but it cannot be rated less than 125% of the load, whether or not it is a standard size. These rules are the same for branch circuits in 210.19 and 210.20.
• August 19, 2019 6:42 AM PDT

  in the topic Branch circuit in the forum Electrical Engineering

  12 AWG is enough.
• August 15, 2019 9:26 PM PDT

  in the topic Receptacles in the forum Electrical Engineering

  Two circuits in the same box can have be protected by two different single-pole breakers
• August 1, 2019 4:57 AM PDT

  in the topic UPS efficiency in the forum Electrical Engineering

   The fact is that most UPS manufacturers quote UPS efficiency at 100% load because it represents the very best efficiency the UPS will attain. If this UPS runs at 50% of the load, will it have same efficiency or not?