Here is a picture of the amp guage showing how it stays all the time the engine is running, except for the first 2 or 3 minutes when it reads about 6 to 8 amps while the battery is being recharged from starting. This picture was taken with my engine at idle. As Tom mentioned when you have a regulator it is a big help for the battery. I'm still using the same 6 volt battery I bought from a recycling yard 6 or 7 years ago. I've never used a battery tender on it, and never had to add water. It sets untouched for 6 months over Minnesota winters, and fires right up in the spring. The second picture shows the electronic voltage regulator in my 3 brush powerhouse. It takes about 5 minutes to remove the third brush and screw in the EVR. Another benefit of the EVR is less drag on the belt and engine, because the generator isn't working any harder than needed by overcharging the battery.