Perko switch & alternator

[EarmarkMarine]

Yes, I agree that it can be true but you have to qualify the conditions as mentioned above. For example, if I had two or three completely depleted and large stereo batteries after playing the stereo agressively for a long duration at rest, I would not want to suddenly introduce these two or three batteries, a large stereo that is continuing to play plus the boat operations to the alternator. The alternator might be rated at 100 amps but only at higher rpms and for an intermittent load. So if the two or three dead batteries initially represent a total 40 or 50 amp load until they get a bit of a charge plus a 50 amp continuous stereo draw plus 20 amps of boat operations then you are running the alternator as hot as an exhaust mainifold while simultaneously pulling down the voltage on the starting battery. So under these extreme circumstances pick one...either recharge the batteries or play the stereo. If these two stereo batteries are still at 50 percent charge or better then ease up on the stereo for the first 15 to 20 minutes while underway again to allow the charging system to catch its breath so to speak.
The larger your audio system the more battery capacity you add and the more your charging system becomes dependent on AC shore charging for proper restoration, not to mention desulfation. Your batteries will thank you. Your alternator will thank you. And, you may notice a performance difference in the audio system quality and battery(s) the following weekend.

David
Earmark Marine

[bzubke1]