Reducing Humming Sound

arvincastro OP80 posts03-17-2020 6:53pm@oldhvymec  

While I would love to see what you find out, I do hope you know what you’re doing...please stay safe!

Arvin

Arvin you are a fine fellow, and I will. Here is something my brother, whom I love only like a brother can, taught me. BTW he's retired now but a good and SAFE electrician, by all of his piers. Not me, I know he is..

WHEN the circuit is hot....YOU know it's hot, you know because YOU CHECKED.

Put one hand in you back pocket. PUT ONE HAND IN YOUR BACK POCKET..., hold your pocket. now work with the other hand..

It has never failed me working around a lot of 5-200kv gen sets. Confined space and visual issues.. Trailer mount enclosed..

In this case, two handed and unplugged, to remove the cover.
Find the caps and discharge them. simple to do, BUT noisey
sometimes..pops and such. I use a simple 40 watt bulb #12 wire with
wire clips and a light switch in an elect box..Clip both sides of the caps and flip the switch, a couple of times... and go to each one a couple of times...AGAIN in the box: use one hand to connect, and one hand in you pocket..

Then flip the switch. if you like a little distance. hee hee use longer leeds.. 

WHY??? You don't want it to go through your chest, the discharge can hurt you but through your chest... ok HAND IN YOUR POCKET.

holes in the shoes is a no no too. ok.. water is a no no. NO WATER, or liquids..EVER...DAMP flooring or kneeling is a no no... the path to ground can be a real issue....

Regards

By the way. AVA sells their gear with a 30-day return period, so if you try a HumDinger, it can be returned if it doesn't help.

Ok I took it apart.  I'm gonna put a better conductor in the box and hard wire mine in with a shorter cable and a pure copper end.  It has some very small caps inside on a logic board. NO problem with having to discharge ANYTHING....
The transformer has 4 corners, two are secured through the faceplate via the front handle and two are secured directly to the faceplate.  NO vibrational dampening of any type. 
Silicone is the best. Make sure it's NOT for ultra high temp. They use nickel, lead, or tin ALL conductive in some of the cocktails with silicone to get the temp rating HIGHER.
Clear silicone is fine temp wise.   I'm gonna look for silicone washers to go between the two mating surfaces. Fireproof dampening stick on stuff, or I'll just run beads of silicone the length of the enclosure let it set up. Thin bead of silicone on the mating surfaces and put it back together.

I used a thermal gun BEFORE the upgrade after an hour of running 85 degrees, room temp was 70.  We'll see if there is any change temp wise, after the silicone.

It is just a noisy enclosure. Should be easy to fix...

Regards

@oldhvymec

Thanks for the report and I am very happy to hear it wasn't too trying a chore for you!  I actually sent your findings to a friend of mine who happens to be an electrician and he said it looks pretty straight-forward...we're hoping to meet up sometime after this COVID-19 business allows us to try silencing the enclosure as you've stated.

Thanks again...Hope you and yours are well!

Arvin 

I took it apart and just used silicone, about a half a tube. I checkerboarded the inside and gave it a little smear. I didn't remove the transformer, I just put a good amount around, the mounts. I also wiped a thin layer on one side of the mating surfaces. Next day back together, about half the noise. I cut two pieces of  in/outdoor carpet close to the same size, one top one bottom, and placed an active XO on top. Pretty quiet now. About 1/2 again. I think with a stick on sound killer, 80% of the noise will be gone.  I'm at about 60% with the carpet..and silicone..

Regards