I have a Powerline 120 amp alternator and an Incharge Heart regulator. In the past, I could run the engine at 1,000 RPM to charge the batteries while at anchor. On our last anchor out, at idle--800 RPM, the battery monitor shows about a 4 amp loss, and doesn't show neutral (no gain or loss) until about 1,150 RPM. Not until 1,350 RPM could I get 22 or 23 amps. I put on a new belt, checked the fuses, looked for any corrosion or bad connections, opened the regulator. I don't remember exactly how many amps I used to get at 1,000 RPM, but it was probably double what I'm getting at 1,350 now. I've read trouble shooting guides but nothing seems to address this. Any ideas would be greatly appreciated. Thanks