Waeco sine wave inverter making a noise

[Chris]

Guys, remember those Waeco inverters we bought - I had a sensible 600W version but I know had some with the nuclear fusion option. Well, mine is working, but makes a shrill squealing noise all the time it's running. Like a sort of whistle alarm. Power source is good, thick cable, proper earth. Had a look inside, obviously I'm a total genius at anything electronic, so I dried it with a hair-drier. All looked in order. No fault lights showing.

Any clues? I plugged in a halogen flood light and an angry grinder and they both worked OK.

I have a selection of hammers if that helps.

Ta

C

 

[Jon Wildsmith]

Sounds a bit high pitched for a fan but have you taken the cover off to see if there is one? If it's not the fan then you might as well hit it with your selection of hammers until it stops, possibly with a loud noise and escape of magic smoke

 

[Chris]

Jon, good suggestion.. Didn't think of that, but the fan does seem to be running very smoothly. I spun it up with the hair drier and it never made a noise, and spun for ages afterwards. It is immediate though when you switch on and off.

I may reserve the hammers for when the magic smoke actually starts escaping.

Chris

 

[Chas]

Rather than something mechanical like the fan could it be something electrical vibrating? Now, now Mavis!

 

[Chris]

Like a very fast oscillation, Chas - like a quartz crystal does in a watch. Hmm, could be. Couldn't see anything in inside like that. Didn't run it with cover off either. Usually when there is a fault, these thing just stop working - but it works. It's quite loud though. Figured it was a low power input alarm. But supply is right up there.

Chris

 

[AndyCook]

i am sure mine squealed like a pig when i ran drill off it which was pulling too many watts
an alarm noise and a light came on too i think...but i maybe wrong..

 

[Chris]

Unfortunately Andy, it squeals with no load on it at all.

C

 

[majic79]

One of the coils more than likely, try using a bit of hot glue to stick them down securely to the board - touch them with something (insulated!) while they are running to see if the sound goes away

 

[Chris]

I shall put my extra thick gloves on and use a drumstick.

Chris

 

[Crispin]

Chris, with a leather gloved finger, poke the fan while it is spinning and stop it. I've had a few of those computer-typed fans squeal on me. The cheaper ones just use a bronze bush which wears. Spinning them by hand or other means does not always cause it. A replacement fan can probably be obtained of fleabay for a a couple of Pounds.

Another thing could be the transformer (big square metal thing inside) delaminating. This would produce more of a hum/buzz like a neon light.

 

[Chris]

Crispin I know what you are saying and I'll add that to the list but it doesn't sound like fan warble
I had that on my MIG recently

It sound more like a high pitched alarm

C

 

[Crispin]

The noise I am referring to is not a warble, it's a squeal. One of my PCs here current suffers from it. Takes a lot of poking before it stops and spins normally.

Somewhere inside there will be a buzzer. It'll look something like this:


Stick a blob of blutak over the top of it and see if it stops. If it is the buzzer then it is an alarm which the invertor thinks is happening.

 

[Chris]

Thank you for that Crispin. I shall whip my top off and see what's going on

C

 

[Chas]

Thank you for that Crispin. I shall whip my top off and see what's going on

C

Do we get pictures of Chris topless? Phwoar!

 

[Bobby Brown]

Do we get pictures of Chris topless? Phwoar!

 

[Chris]

Jeez no. There are laws you know. Here's what it sounds like..

http://www.youtube.com/watch?v=l9s-Mt27iyI

Wasn't there an img- img button thingy somewhere. It's all bit beyond me.

Chris

 

[silvercruiser]

It does sound like an alarm sounder rather than a squeal. have you got your top of yet and had a prod

 

[Jon Wildsmith]

It does sound like an alarm sounder rather than a squeal

sounds like that to me as well. Switch mode devices can oscillate and squeal but this doesn't sound like that to me.

 

[Chris]

Well pretty sure it's not a love voltage input alarm. It's got plenty of zip in the battery. There is staggeringly little inside the box when you open it up. I expected chimneys in there puffing out smoke and coal fired boilers raging away, being stoked by tiny little men in donkey jackets.

But no. All very boring.

C

 

[Crispin]

Nope, that sound like an alarm.
I'll ask the guy I got them from if he has any manuals for them - might be a clue in there.


I have some spare invertors if you want?