Run Capacitor Microfarad Check
The in-circuit capacitance of a motor run capacitor from the measured volts and amps (C = I / (2 x pi x f x V) at 60 Hz, the ~2652 x amps / volts field rule) compared to the nameplate rating and an editable +/-6% tolerance band, with a good / weak / replace verdict.
Formula and source
measured_uf = 1e6 x I / (2 x pi x 60 x V) ~= 2652 x measured_amps / measured_volts (the in-circuit capacitance from Xc = 1/(2 x pi x f x C) at 60 Hz). Band = rated_uf x (1 +/- tolerance%/100); within / below / above gives the good / weak / replace verdict.
First-principles capacitive reactance (public); +/-6% run-capacitor tolerance is the common motor-capacitor convention (by name).
Audience
This tile is built for hvac and the adjacent professions in the HVAC group. The interactive calculator runs entirely in your browser. No account, no fee, no advertising, no tracking.
Related tiles
Posture
Rough Logic answers the math question the working professional asks on the job. The site is a calm, fast, ad-free, account-free, ever-free reference. It does not interpret code. It does not replace the licensed professional. It does not store your inputs. The Authority Having Jurisdiction governs all installations and inspections.