I'm wiring a 3-phase air conditioning unit with an auxiliary heating element. The nameplate ratings are as follows:
Volts: 208/230
Min Ckt Amps: 57.8/61.9
Max OCPD: 60/70
Minimum Unit Disconnect: 33/36 (FLA) | 112/112 (LRA)
When I measure the voltage at the subpanel, it's 220V across each of the three phases. I believe the wire should be rated at 60A. But I'm not sure about the HACR type 3-pole breaker: do I rate it at 60A or 70A?
Also, I'm not sure about the rating of the disconnect switch which is to mounted at the compressor unit. I was given a 3-pole non-fused disconnect that is rated at 30A. However, the disconnect's nameplate states: "Suitable for use on a circuit capable of delivering not more than 10,000 RMS symmetrical amperes, 240 volts maximum, when protected by any other overcurrent device rated 30 amperes maximum." (Emphasis mine.)
Volts: 208/230
Min Ckt Amps: 57.8/61.9
Max OCPD: 60/70
Minimum Unit Disconnect: 33/36 (FLA) | 112/112 (LRA)
When I measure the voltage at the subpanel, it's 220V across each of the three phases. I believe the wire should be rated at 60A. But I'm not sure about the HACR type 3-pole breaker: do I rate it at 60A or 70A?
Also, I'm not sure about the rating of the disconnect switch which is to mounted at the compressor unit. I was given a 3-pole non-fused disconnect that is rated at 30A. However, the disconnect's nameplate states: "Suitable for use on a circuit capable of delivering not more than 10,000 RMS symmetrical amperes, 240 volts maximum, when protected by any other overcurrent device rated 30 amperes maximum." (Emphasis mine.)