Dual alternators, one regulator?

[RaymondR]

Hi s/v Jedi.

What I'd really like to have is a large diameter flywheel mounted, high current, alternator/starter and do away with the hard to get at starter motor, add-on alternator and all those pesky belts.

[s/v Jedi]

Originally Posted by RaymondR

Hi s/v Jedi.

What I'd really like to have is a large diameter flywheel mounted, high current, alternator/starter and do away with the hard to get at starter motor, add-on alternator and all those pesky belts.

I know… I removed those two alternators and a belt driven crash pump and then got rid of that last V belt as well when ai installed the serpentine belt kit. It was all I could do cleaning up all the bolt-on stuff with what is available. I estimate I got rid of 100kg weight from the engine!

[pbmaise]

Originally Posted by Bycrick

Balmar apparently still makes an MC612H which is specifically designed to run 2 alternators on the same engine to a single battery bank.

Learn something every day. I didn't know about this regulator. My engine ran twin alternators.

Description
Regulator, Dual MC-612 Multi-Stage, 12v, w/Harnesses

For Use with Twin Alternator, Single Engine Applications

Part Number without Harnesses: MC-612-DUAL

[R Hutcheson]

The short answer is yes. My boat came from the factory with a similar set up. The BalMar regulator I have is designed for one alternator, yet it controls two. It is connected in such a way that it sees both alternators as a single unit. Unfortunately, that is all the information I can give, as the setup makes no sense to me at all. I had to bring in help to sort it out last time I had a problem. I can tell you that BalMar does make regulators which are designed for use with two alternators. If your reworking the system, and not a knowledgeable as you might wish, that option might be a more straight forward way to go.

[Larryo]

<<<< Originally Posted by Bycrick
Redundancy isn’t always better. Ask pilots about twin vs single engine planes. Adding more of something is inherently less reliable; there’s more to break and go wrong.>>>>>>

Originally Posted by JC Reefer

Good points BUT not sure the plane analogy is one I would have included. Being on a plane where ONE engine failed I was content with the other doing the job. [emoji6]

Well, it all depends. Redundancy has it's advantages, even with the inherently less reliable philosophy. With the airplane, one can look at the ENGINE OUT situation, where have two is significantly less than having one, even though the single is more reliable overall. So, the argument could be made with "how hard is it to control the plane on one engine".


I like my twin engine plane for the above reason. I like my twin engine boat for similar reasons, but maneuverability is on big reason, no so useful in a plane.


Another issue is "what's the consequences should one fail?" If you only have one engine, might ruin your day.



And, I could argue both sides of the twin vs single in both boats and planes.


For now, believe I'll get a single regulator for a twin alternator install.

[sailingharry]

Originally Posted by EngineerRetired

twin engine / alternators, single regulator. $270 https://www.westmarine.com/buy/balma...ecs-_-DY-_-PDP

I believe the center fielder is not a regulator, but a regulator controller. You would still need two additional regulators.

[sailingharry]

Originally Posted by Bycrick

It makes no difference whatsoever how many charging sources one has connected to a single battery (bank). The battery itself, based on chemistry and state-of-charge, determines how much current it will accept at a certain voltage. If there are multiple chargers, they’ll share the current. Will they share it equally? No, but who cares?

This! So many people worry about the fact that one charger falls off first, but it doesn't matter. If you are holding the battery at 14.2 volts, or whatever appropriate voltage, you are doing all you can do!