ss electric1
Member
- Location
- nc
hvac condenser unit. name plate states , 50 amp cb, min. circuit amps. 28. fellow co-worker says #10. I say #6.
thanks for info.
thanks for info.
hvac condenser size cb & conductors
- Thread starter ss electric1
- Start date
- Status
texie
Senior Member
- Location
- Fort Collins, Colorado
- Occupation
- Electrician, Contractor, Inspector
#10 it is. It works even at 60 degree for NM cable. The wire size does not have to match the beaker for this application. That is urban legend.
- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
The overcurrent protective device (Breaker) is only there for ground fault and short circuit protection. The a/c unit has overload protection built in and that will control the current getting higher then the wire can handle.
- Location
- New Jersey
- Occupation
- Journeyman Electrician
Also with an MCA of 28 amps you could use a 30 amp OCPD.
- Occupation
- Licensed Electrician
Co-worker wins the bet, 240.3 tells you it is okay.
- Location
- Placerville, CA, USA
- Occupation
- Retired PV System Designer
But although it is acceptable, it may lead to nuisance trips. Mike recommends going to the max allowed OCPD instead.
Tapatalk!
StarCat
Industrial Engineering Tech
- Location
- Moab, UT USA
- Occupation
- Imdustrial Engineering Technician - HVACR Electrical and Mechanical Systems
Spot on
Spot on
Gold Digger is spot on to go with MAX breaker size.
This is always the best thing with HVACR compressor loads especially single phase because of the inrush starting characteristics.
Even with MAX size breakers, single phase condensing units often require hard start components to be added after the install.
Myself and others will install hard start regardless as it will moderate the starting current. This lessens other side effects of bringing such loads on the line which end users often have perceptual difficulty with.
Spot on
Gold Digger is spot on to go with MAX breaker size.
This is always the best thing with HVACR compressor loads especially single phase because of the inrush starting characteristics.
Even with MAX size breakers, single phase condensing units often require hard start components to be added after the install.
Myself and others will install hard start regardless as it will moderate the starting current. This lessens other side effects of bringing such loads on the line which end users often have perceptual difficulty with.
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