Fan interference????

[Ironman]

Hi, I've noticed a noise coming from my extraction fan when it's running at 25%! I thought my fan was on its way out!😲

Today I went in to take pics of my girls and switched the lights off at the mains for a better pic. The fan sound stopped. It was silent again. So I switched the light back on and it was lumpy again.

I have my ballast about 6 inches from my fan!

Anybody heard this before?

sent from Thames Ironworks

[Viz]

When your fan is running slow the frequency that is created by the spinning coil in the motor will create a harmonic, that frequency of the harmonic may be low enough to be in sync and interfer with the low frequency square wave of the ballast. Remember all electronics has a emission a bit like the iron filings and the magnet experiment you may have done at school. So when those lines intersect or cross there may be interference. See what happens if you place a metal dish or bucket over the ballast and if it goes away then you have proof of the interference. I would suspect it would only happen at very low setting in the fan motor.

[Loki]

Very strange indeed Ironman. Have you tried moving the ballast away from the other electronic devices.

[Ironman]

When your fan is running slow the frequency that is created by the spinning coil in the motor will create a harmonic, that frequency of the harmonic may be low enough to be in sync and interfer with the low frequency square wave of the ballast. Remember all electronics has a emission a bit like the iron filings and the magnet experiment you may have done at school. So when those lines intersect or cross there may be interference. See what happens if you place a metal dish or bucket over the ballast and if it goes away then you have proof of the interference. I would suspect it would only happen at very low setting in the fan motor.

I will try that in a bit mate. 😉

sent from Thames Ironworks

[Ironman]

Very strange indeed Ironman. Have you tried moving the ballast away from the other electronic devices.

That is my next move mate, it's strange how it's only been happening for a couple of days.

sent from Thames Ironworks

[Loki]

That is my next move mate, it's strange how it's only been happening for a couple of days.

sent from Thames Ironworks

How old is the ballast?

[Ironman]

How old is the ballast?

Not even a year. It's done 1 grow!

sent from Thames Ironworks

[Viz]

Same ballast as what I have Iron? The Maxibright?

[Viz]

Going to go into the shed and set my fan at 25% and see if I get the same thing happening.

[Ironman]

Same ballast as what I have Iron? The Maxibright?

No, I got the omega 600.

I just put the bottom half of my bowl trimmer made of metal ( thanks loki) over the ballast and it stopped the noise.😉

I'm gonna move my ballast away and hope that does the trick😆



sent from Thames Ironworks