Here is a quote from JYD concerning a 946C generator:
"Your generator at driving speed, with nothing on, should put out between 10 and 12 amps max. Of course that will decrease some as you turn on your lights and etc. At idle with nothing on the output should be about 2 amps or so. At idle with the headlights, dash light and taillight on you should have a discharge of about 2 to 5 amps, maybe even a little more depending upon the condition of the generator. Driving at speed with the lights on the ammeter should read around 0 or 1 or 2 amps on the charge side."