Marty Fitzhenry posted:John, yes the 220 will work. So will many others. With Jason, time was spent to come up with that value I posted. Bottom line, we have been doing this for years with not ONE issue.
There is one reasonable explanation for a higher value. If the lighting FET does fail and put full PV voltage on it, a 560 ohm resistor would not put unreasonable currents through the LED, and you'd be less likely to have it burn out as well.