Balmar Max Charge MC-612 Question

[smac999]

Originally Posted by dksail

I measured the voltage at the alternator positive with the same ground as the voltage sense and it reads 14.1V. Is this normal? Testing to engine as ground was 14.1 as well.

I replaced the voltage sense wire with a new wire running directly to the battery reducing voltage loss and that had no impact, the voltage sense was still reading 14.1V.

This last test indicates to me that the voltage sense on the regulator is bad. Thoughts?

so the alternator is 14.1v at it's post, and the balmar shows a BV of 14.1v, and your house bank is 13.4v?

that issue would be the cables between the alt and the house bank.

when you moved the sense direct to battery. you said the BV stayed the same at 14.1v (I would expect that), did the battery voltage and alternator voltage both go up? to say 14.8v at alt and 14.1 at battery?... and bv would still be 14.1v

are you sure you don't have a battery isolator in the system? you are losing 0.7v. which is the drop of a old battery isolator.

[dksail]

Ding...Ding...Ding... We have found the problem. Waterman 46 completed the journey that everyone had a part of solving. Should I have found this sooner? Yes. Would it have uncovered the real issue? No.

After reviewing the boats wiring diagram compared to actual, of course it was wrong. Turns out that the alternator ground is at the engine, and with a separate negative from the engine to the bus bar. Therefore the big voltage drop was in the negative sensing wire. Had I just followed Maine-sail’s advice and hooked both sensing wires directly to the battery, the regulator issue would have been solved, but I would not have discovered the alternator grounding shortfall.

So, thanks to you all!

Is it important that the alternator is grounded directly to the bus bar? Or can I live with that voltage drop in the alternator circuit? I realize it would be more efficient if it was.

[witzgall]

You are thinking about the MC-612Dual. The MC-612 was the predecessor to the MC-614, and is designed for single alternator applications.

Chris

Originally Posted by CharlieJ

MC-612 has the same features as the MC-614 but controls two alternators on the same engine. OP: what is your setup...do you have two alternators on one engine?