weird garage door problem

[lukasz]

Ok, so i narrowed it down a bit, so the interference is around 500(possibly lower couldn’t go any lower with AM) and 1k. when we turned the belt on and off it for sure start to mess with the AM radio very harshly.

just to clear this up it isnt a bake oven its a drier, a VERY LARGE one, runs in 220v.

ljcox, as far as those ferrite beads and sleeves, that site isnt pulling anything up in the search, it says

"No products were found that match the keyword(s) LF-1250 Ferrite Bead. Please try another search keyword."

am i looking in the right place?

so your saying i have to shield all the wires that go from the motor to the speed controller? im kind of confused on the open and closed thing. sorry im still not all that great with electronics i know impedance is resistance but im not quite sure what you mean by winding it twice? and how that would increase the impedance, maybe im thinking of the term in a wrong way.

 

[Sceadwian]

Impedance is not resistance, impedance is complex and frequency dependant.
The ferrite 'bead' is just a slug of metal that you place around the wire, what he means by wrap it more than once is coil the wire a little a few times so more than one loop passes through the ferrite bead, this increases the RF killing effect of the bead. The more coils you can fit throug the ferrite bead the better.

 

[ljcox]

Ok, so i narrowed it down a bit, so the interference is around 500(possibly lower couldn’t go any lower with AM) and 1k. when we turned the belt on and off it for sure start to mess with the AM radio very harshly.

I think you mean 500 kHz to 1 MHz.

ljcox, as far as those ferrite beads and sleeves, that site isnt pulling anything up in the search, it says

"No products were found that match the keyword(s) LF-1250 Ferrite Bead. Please try another search keyword."
am i looking in the right place?

That's odd. I have the paper catalogue. I did not look at their web site.

Did you try searching on "ferrite" or just "LF-1250" or "LF1250"?

so your saying i have to shield all the wires that go from the motor to the speed controller? im kind of confused on the open and closed thing.

I said to put a ferrite bead on each wire where it goes into the electronics box.
Did you find the LF-1290 in the JayCar web site? The paper catalogue has a photo. Let me know if you can't find it, I'll take a photo of one that I have and post it in the forum.

sorry im still not all that great with electronics i know impedance is resistance but im not quite sure what you mean by winding it twice? and how that would increase the impedance, maybe im thinking of the term in a wrong way.

See the reply from Sceadwian above. However, ferrite is not metal, it is ferrous compond. So it contains iron but is, strictly speaking, not a metal.

 

[lukasz]

i found a good document on how to install these too incase anyone wants/needs to look at it.

https://www.electro-tech-online.com/custompdfs/2007/01/321221a.pdf

 

[lukasz]

ok so according to this manual i just install one on either end of the hardware? is that correct?


oh also that snap on noise supressor says "This offers impedance (peak approx 300at 2- 300MHz) with negligible impedance below 1MHz"

but the interference seems to be 300 and up as well, so will this work?

 

[Sceadwian]

What's the frequency of the garage door opener?

 

[ljcox]

ok so according to this manual i just install one on either end of the hardware? is that correct?

Install one on each wire that goes into the electronic control box. And wind the wire around as many times as possible before snapping it closed.

oh also that snap on noise supressor says "This offers impedance (peak approx 300at 2- 300MHz) with negligible impedance below 1MHz"

I don't know what frequency your garage door controller is. Mine is 433 MHz.

but the interference seems to be 300 and up as well, so will this work?

That depends on how much loss it has at the 400 MHz region assuming your garage door control is in this region.

By winding it through as many times as possible will increase the impenance.

 

[lukasz]

ahhhhh impenance, first time i read it impedance, or resistance. no wonder i was confused.

ok so as for installation still kind of confused. so theres wires that go from power to the box, then from box to the motor. so your saying this (im simplifying it quite a bit):

[motor] ====== (Ferrite Bead) =[control box] =(Ferrite Bead) ==== [ power box ]

and wind it. is there anything else that would increase impenance?

 

[lukasz]

What's the frequency of the garage door opener?

not sure, is there a way to tell?

 

[Sceadwian]

Look at the remote or the opener itself, or the manual! =)

 

[lukasz]

aha! genius.

stupid me ill do that first thing at the shop tomorrow.

 

[ljcox]

ahhhhh impenance, first time i read it impedance, or resistance. no wonder i was confused.

ok so as for installation still kind of confused. so theres wires that go from power to the box, then from box to the motor. so your saying this (im simplifying it quite a bit):

[motor] ====== (Ferrite Bead) =[control box] =(Ferrite Bead) ==== [ power box ]

and wind it. is there anything else that would increase impenance?

I assume that there are no electronics in the Power Box. If so, then the ferrite beads need to be at the control box as you indicated.

Do you mean a ferrite bead? Or a ferrite hinged core?

If you are threading the beads on to the wires, then put 2 or more beads on each wire. Each bead will increase the impedance.

And if you can insert the wire through the bead more than once, then that will also increase the impedance.

If you mean a ferrite hinged core, then wind the wire through it as many times as possible but not so many that you can't snap it shut.

 

[Roff]

Maybe we should point out that all turns need to go in the same direction. If you stick a loop of wire through the core, it will have absolutely no effect. This may be obvious, but maybe not to the noob.

 

[ljcox]

Maybe we should point out that all turns need to go in the same direction. If you stick a loop of wire through the core, it will have absolutely no effect. This may be obvious, but maybe not to the noob.

Good point Ron,
Just to clarify what he means:-

Don't bend the wire into a U shape and push it into the ferrite bead. The wire has to be unterminated and pushed through the bead as many times as you can. Then re-terminate it.

Or if you have the hinged ferrite core, wind the wire around it as I described previously and snap it shut.