Reading an HVAC nameplate — MCA sizes the wire, MOP sizes the breaker
Two numbers do all the work: wire ≥ MCA, breaker ≤ MOP. On HVAC the breaker may legally exceed the wire's ampacity (Art. 440) — that's normal, not an error.
What this diagram shows
A drawn air-conditioner nameplate highlighting the two electrical values that size the circuit: the Minimum Circuit Ampacity (MCA, 21 amps in this example) which the conductor rating must meet or exceed, and the Maximum Overcurrent Protection (MOP, 35 amps) which the breaker must not exceed. On HVAC equipment the breaker may legitimately be larger than the wire ampacity under NEC Article 440 — the nameplate governs, not the generic table. Example values from a 3-ton Goodman condenser spec.
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