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Motor circuit (MCA, breaker, wire)
Electrical tool — Motor step. Enter any nameplate value a refrigeration mechanic copies off the plate.
Nameplate inputs
- Type FLA, RLA, MCA, or MOP. Last values you type stay put; the rest fill live.
- FLA and RLA are the same running amps (motor plate vs compressor plate language).
- Derived MCA ≈ running × 1.25 (1 motor), or 125% of largest + 100% of the others.
- Derived MOP = next standard breaker ≥ MCA. No inrush multiplier. If the plate lists MCA and MOP, enter both.
Wire size (80% of breaker)
- Wire is sized for breaker ÷ 0.8 (continuous), same floor as the Power step.
- 15 A always → #12 AWG Cu (not #14).
Phase & capacitors
- Choose single-phase or three-phase.
- Start/run capacitor µF is single-phase only. Three-phase capacitors are engineered — see VFD / Starters.
Disclaimer: Does not apply full motor-branch exceptions. Consult CEC/NEC or IEC and the AHJ. Terms §3.1.