RMS
Member
- Location
- Minden, NE, USA
I field assemble our HVAC digital temperature control panels. The panel typically includes atleast (1) 120:24vac 100va transformer, digital temperature controller(s), 24vac devices, relays (switching 24vac loads), strictly low voltage in the panel except for the 120V branch circuit supply the transformer(s). How do I calculate the fault current available on the branch circuit and downstream of the 120:24vac transformer. My local inspector told me I need to protect the "weakest" component in the panel. I plan on talking to the project electrical engineer but I was hoping to get a little info on calculations and options to reduce the available fault current if necessary.