Air Marine wind generator woes

[Kabunza]

I’m having the strangest problems. I have an AirMarine generator that runs great off the boat, meaning it spins freely with a puff of air and subsequently produces voltage.
However, every time i install it on the boat it barely spins even with a stiff breeze. I’ve tried testing with the leads not connected to anything. I even replaced the cable that runs to the breaker thinking maybe it had a short somewhere. It’s such a simple system yet I don’t understand why it’s behaving this way. What am I missing?

[skipmac]

Maybe something in the physical installation? Are you using the same pole, same mounting hardware, etc? Could it be the mounting on the boat isn't flat and it's causing something to bind up in the case of the generator.

[Kabunza]

I actually replaced an older generation AirMarine with a newer one. Older one worked perfect, but was worn. New gen points correctly into the wind, but blades have a hard time spinning only when on the boat.

[skipmac]

And when you replaced the old generator did you use the exact same mount, pole, hardware? Did you use the exact same mount, pole, hardware when you tested the new one on land?

Since it works on land and not on the boat then you need to identify everything that is different between the two installations. That includes not just electrical connections but exactly how you physically installed it, what hardware you used, how much you tightened all the nuts and bolts, how level it is.

[40 South]

If your batteries are fully charged it can stop spinning.

[Kabunza]

On land, I tested it just by holding the generator at the base (by hand), since I didn’t have a pole and it spun pretty freely.
At the boat on the other hand it barely turns even though pole is the same. I even disconnected cable from breaker to eliminate potential for stray current.
The clamp at the base is tightened snug. An overtightened clamp wouldn’t affect blade bearings. Also, it easily points to the wind and that’s the bearing that could be affected by an overtightened clamp collar.
Very weird.

[Kabunza]

Originally Posted by 40 South

If your batteries are fully charged it can stop spinning.

I agree. I read that in the manual. That’s with leads connected to battery where it would be sensing the voltage. Internal circuit places it in braking mode when batteries are charged.
In all cases I’ve been testing it’s been with leads disconnected from everything.
I’m tempted to test it with a weak battery to see if does what’s its supposed to. But still doesn’t make sense

[skipmac]

OK, if I understand what you've done.

1. Holding in your, no battery connection, blades spin freely in light air.

2. Mounted on boat, no battery connections, blades do not spin freely in light air.

The ONLY variable I see is mounting the unit on the pole so, as Sherlock Holmes said, "Once you eliminate the impossible, whatever remains, no matter how improbable, must be the truth." IE it as something to do with the mount.

You say the bolts on the base do not effect the blade bearings BUT if the base of the generator or mount is not perfectly flat, tightening the mounting bolts could warp the case of the generator and cause friction or interference with the bearing OR another spinning part like the rotor inside the generator.

Also, I don't see what you will learn connecting a battery. If it spins in your hand with no battery connection and doesn't spin mounted on the boat with no battery connection then you have already compared apples to apples and adding an orange to the comparison doesn't seem to add any information to the basic problem.

Q1. What happens when you spin the blades by hand mounted on boat vs in your hand?

Q2. Do you hear any noises like scraping, rubbing, grinding when the blades spin when the generator is mounted on the pole?

[Kabunza]

Originally Posted by skipmac

OK, if I understand what you've done.

1. Holding in your, no battery connection, blades spin freely in light air. YES

2. Mounted on boat, no battery connections, blades do not spin freely in light air. YES

The ONLY variable I see is mounting the unit on the pole so, as Sherlock Holmes said, "Once you eliminate the impossible, whatever remains, no matter how improbable, must be the truth." IE it as something to do with the mount.

You say the bolts on the base do not effect the blade bearings BUT if the base of the generator or mount is not perfectly flat, tightening the mounting bolts could warp the case of the generator and cause friction or interference with the bearing OR another spinning part like the rotor inside the generator. The pole is pretty straight. Well under a degree. also, old Air Marine spun even when we were heeling. Also, mount is a clamp collar w/ foam insulator. I hand tightened it with hex so its snug and secure. New AirMarine does have added circuitry that keeps blades from turning when battery reaches proper levels. But that shouldn't be afcator with leads disconnected. Other than that it's the same unit.

Also, I don't see what you will learn connecting a battery. If it spins in your hand with no battery connection and doesn't spin mounted on the boat with no battery connection then you have already compared apples to apples and adding an orange to the comparison doesn't seem to add any information to the basic problem. I agree. I've been troubleshooting this for weeks and it's not making any sense. I'm a EE and very mechanical and feel I've ruled out the obvious. The only thing I haven't tried is eliminating the cable that runs to the breaker, although it's disconnected.

Q1. What happens when you spin the blades by hand mounted on boat vs in your hand? Friction feels about the same. Feels like typical sealed bearing friction.

Q2. Do you hear any noises like scraping, rubbing, grinding when the blades spin when the generator is mounted on the pole?

No. Feels very smooth

Thanks skipmac. I've inserted my remarks in blue.

[senormechanico]

Disconnect the wiring from the generator and make sure no stop switch is connected.
Does it turn freely on the pole?
If the batteries are charged, depending on the regulator screw setting (on the side of the tail) it will only turn slowly.
With the setting full clockwise, if I remember correctly it will output to somewhere around 15 volts.

[CarinaPDX]

It sounds like what happens when the output is shorted. At least the early AirMarine units came with a manual that called for a shut-off switch (SPDT) that would either send the power towards the batteries or short it to the ground of the generator. When shorted the blades would either not turn or turn slowly. Every AirMarine should have this switch, at least assuming the newer units work the same way. Leaving the generator running overnight in a crowded anchorage is a great way to make enemies - that whistling sound, which isn't very noticeable below the generator, will drive people on nearby boats to do extreme things... The better option now would be to buy the quiet blades. Anyway, look for a short. Perhaps the pigtail coming out of the generator is shorting to the inside of the pole? Something like that is a real possibility.

Good luck,

Greg

[Kabunza]

Just removed my generator so I can troubleshoot from a bench. Discovered rotor had been primed. Videos I’ve seen don’t show painted rotor. Paint had flaked off in areas that was adding to friction. That might explain why it didn’t easily turn with wires fully disconnected. Removed paint and cleaned up rotor.
Shunt test and voltage test pass. I’m not sure about current test. When I test for current, generator acts like it’s stalled and ammeter shows very low current regardless of rpm. I understand gen is under load, but still doesn’t explain low current.
Does anyone know what I should expect to find when doing a current test? Manual states how to do test, but not what results you should look for.

[Jim Cate]

Originally Posted by Kabunza

Just removed my generator so I can troubleshoot from a bench. Discovered rotor had been primed. Videos I’ve seen don’t show painted rotor. Paint had flaked off in areas that was adding to friction. That might explain why it didn’t easily turn with wires fully disconnected. Removed paint and cleaned up rotor.
Shunt test and voltage test pass. I’m not sure about current test. When I test for current, generator acts like it’s stalled and ammeter shows very low current regardless of rpm. I understand gen is under load, but still doesn’t explain low current.
Does anyone know what I should expect to find when doing a current test? Manual states how to do test, but not what results you should look for.

If you are placing the ammeter across the output leads this essentially shorts the generator, just like the stop switch does and would cause it to spin slowly.

To check the output current you'd need to have the ammeter in series with either output lead with the output going to a battery.

Jim

[Kabunza]

Current is being measured in series