Rutland 913 vibration

[touchwoodtoo]

I have just fitted a Rutland 913. I am pleased with it but I am experiencing a vibration from the unit from about 8kn upwards. The vibration is resonating through the hull and when its quite windy, I'm reaching for the stall switch on the charge controler. I have contacted Marlec who have suggested that the humming is the result of blade vibration and this can be expected. They suggest damping the supporting structure with rubber pads and then, if necessary, fitting additional mast supports to break up any harmonic. Has any one experienced this charachteristic, and if so how did you tackle the problem? I spoke to several people over the summer who have not been troubled. Is this anything like common?

 

[CSFenwick]

Ours is mounted above our cabin (aft cabin Moody) and you do get a certain amount of vibration/humming/resonance. Has bothered me less as time goes on. As you say you can just stop the blades but if you think of it as all those Amps going in it can actually start to sound quite pleasant!

 

[Shanty]

Fitted a 913 a couple of years ago. I was surprised by the amount of vibration, so I sent it back to the manufacturers, who decided that the blades were out of balance. They supplied me with a new unit which produes far less vibration - only detectable if you touch the mounting pole.

 

[TonyS]

The boat next to us at Beaulieu on Saturday night had one fitted. It made a horrible noise in the wind gusts. My feeling is they are rather antisocial and should only be used at anchor. It disturbed him enough to stop it and tie it up.

 

[[10753]]

I have had 913 fitted for 2 years now on a gantry welded to the pushpit.

All I get is the occaional whooooshing sound. I have never had the need to tie it down due to noise.

Despite this I thinkit does put people off mooring next to you!

In fact I only find it annoying when the sun is behind the blades and you get a strobe effect !

Maybe you could try removing, swapping and reseating the blades ?

Good luck

 

[Rivers & creeks]

Rubber pads help, so did a rope in tandem with the fixed diagonal support. If you have a grinding noise then it's a knackered bearing, but they replace them for £15 plus £30 labour!

 

[LadyInBed]

My 913 is on an L bracket on the mizzen. When I fitted it I cut a pad from a car inner tube to act as a shock pad between the bracket an the mast. I sleep in the aft cabin directly below the mizzen, no vibration only a satisfying whoosh as it pumps amps into the batteries /forums/images/graemlins/smirk.gif
It has been in situ for six years now.

 

[roger]

Just guessing

A large lump mounted on the end of a metal pole is likely to be pretty resonant. Tap it and see whether you get a distinct note. There will be vibration in the pole when the generator is running if only from effects when each blade goes by the pole.
The only generator I've handled had a lumpiness when I turned the rotor due to the permannt magnets. That could be enough to give vibration.
At some wind speed you are bound to get resonance - and vibration etc. in the cabin. The boat too is a light, rigid and resonant structure.
Damping the vibrations is a matter of trial and error. Rubber at the mounts, perhaps some sort of filling in the pipe, additional guy wires also with damping. These are only suggestions.