Alternator clutch on Yanmar 4JH3te

[ski69sail]

Thanks in advance for your input

I have a 75hp Yanmar 4JH3TE turbo with an 80 amp Yanmar alternator on my yacht. I am interested in installing either a manual or electric clutch on the engine that runs the alternator. I would like to be able to disengage the alternator during long voyages.

[Celestialsailor]

Mind if I ask why?

[ski69sail]

Hi There

I believe the alternator is creating static electricity on long 10 hour plus motoring trips. This is only a hunch at this point.

I have a remote regulator I have had all my electrics checked over by a reliable marine electrician on numerous occasions, but I am still having electrical anomalies affecting various equipment on the vessel.

Thanks Raymond

[transmitterdan]

Originally Posted by ski69sail

Thanks in advance for your input

I have a 75hp Yanmar 4JH3TE turbo with an 80 amp Yanmar alternator on my yacht. I am interested in installing either a manual or electric clutch on the engine that runs the alternator. I would like to be able to disengage the alternator during long voyages.

This can easily be accomplished without a clutch. Install an external regulator with a shutdown feature. You can then switch off the alternator via a switch. Removing the field current from an alternator will shut it off the same as a clutch.

But really there is no need for doing this when you have an external smart regulator. It will shut down the alternator automatically if you program it right. Balmar and others make such regulators.

[transmitterdan]

Originally Posted by ski69sail

Hi There

I believe the alternator is creating static electricity on long 10 hour plus motoring trips. This is only a hunch at this point.

I have a remote regulator I have had all my electrics checked over by a reliable marine electrician on numerous occasions, but I am still having electrical anomalies affecting various equipment on the vessel.

Thanks Raymond

Do you mean there is interference or noise generated by the alternator? Does it cause some effect you can describe? Static electricity is not something an alternator can create.

[a64pilot]

Actually a motor or an alternator if brushed can create static electricity.
We have just gone through an issue with electric fuel pumps, apparently the dust and brushes were generating a high static charge that was being discharged through the brush block and damaging the armature, the fix seems to have been both grounding the motor with a ground wire and the motor housing being cad plated as opposed to being painted, cadmium conducts electricity, paint doesn't.
I would ground the thing if you suspect it's building static, yes I now it is already grounded, but the case may not be well grounded, and an additional ground wire can't hurt anyway.
I think it unlikely, but then I didn't believe that was the problem with the fuel pump either.

[Celestialsailor]

I'm wondering how static could build up unless the alternator is somehow isolated from the engine's ground and prop shaft for that matter.

[Cadence]

MHO is you are opening a big can of worms unnecessarily. You may consider filtering power to your electronics or shielding them, just as an far flung idea. You might consider seeing what may be turning on or off when you have an electronics problem.

[Compass790]

Originally Posted by ski69sail

Thanks in advance for your input

I have a 75hp Yanmar 4JH3TE turbo with an 80 amp Yanmar alternator on my yacht. I am interested in installing either a manual or electric clutch on the engine that runs the alternator. I would like to be able to disengage the alternator during long voyages.

The switch in the field wire is the easiest way to depower the alternator but make sure it's a DC switch ( dont ask me how I know). Dont know enuff about yr static problem to know if that will fix it tho as the rotor will still be spinning

[seabreez]

Originally Posted by ski69sail

Hi There

I believe the alternator is creating static electricity on long 10 hour plus motoring trips. This is only a hunch at this point.

I have a remote regulator I have had all my electrics checked over by a reliable marine electrician on numerous occasions, but I am still having electrical anomalies affecting various equipment on the vessel.

Thanks Raymond

I do not think that an alternator can create static electricity as you have "alternating" current and therefore the positives cancel out the negatives and therefore cannot produce "static." What problems are you having? I have never seen someone turn off an alternator. Try me as I have solved many problem with electronic interference...

[hhmsailor]

You may want contact Maine Sail regarding these issues.


compassmarineservices@gmail.com

[transmitterdan]

The OP has gone silent. I suspect the issue is that the alternator causes static interference in some electronics such as the stereo or VHF radio. That would not be the result of "static electricity". Alternators have 6 phase rectifiers and can create a high frequency noise signal that varies with engine RPM. Depending on how the power system is wired this noise may be present on the DC bus. It most often happens when the output of the alternator does not run directly to the house battery. But it can also happen when the alternator output + and - wires are run far apart yet close to other equipment wires.

The solution is to run the + and - wires from the alternator directly to the house bank keeping both wires close together the entire run and separated from other wiring. A lot of installations don't take this care in the wiring.

[a64pilot]

To cut alternator whine on aircraft radios, often a capacitor is added to the output. It does help.
http://www.aircraftspruce.com/catalo...torfilter.php?
There are cheaper capacitors of course as we don't need FAA / PMA parts on boats.