RC calculation
T=RC, so:
Time
Resistance Capacitance
or
mS
Kohms uF
or
Seconds
ohms F
The result gives you 1T. This is 1 time period. So for 1000uF and a 1K resistor T = 1000mS
For charging and discharging a capacitor:
1T 63%
2T 86.5%
3T 95% (this tends to be the default usage with 95% considered basically there)
4T 98% (this tends to be considered as 100% charged / discharged)
(in theory 100% is infinite)
Different voltages don't change the time to reach 1T, but will of course change the voltage measured at 1T (63% of the applied voltage). E.g. if a 12V supply is connected via 1K to a 1000uF cap it would take 1000mS to reach 7.56V, 3000mS to reach 11.4V. Its exactly the same for discharging a capacitor.
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