Service Equipment Sizing for A/C Loads: MCA & MOP Explained
5:13
That A/C nameplate already has two numbers you need to know.
In this lesson: MCA (Minimum Circuit Ampacity, the conductor floor) vs MOP (Maximum Overcurrent Protection, the breaker ceiling), two full worked examples, why hermetic compressor motors use RLA/BCSC instead of standard motor math, HACR-rated breakers, the 440.14 disconnect requirement, fuse vs breaker MOP, multi-motor units, and what to do if the nameplate is missing.
Based on the 2023 NEC (Article 440).
