Author Topic: Long wire interference  (Read 2083 times)

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Offline adaschau2Topic starter

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Long wire interference
« on: December 09, 2011, 01:39:01 PM »
Hi all. I'm currently working on a project that requires me to place a tactile switch a sizable distance away from my microcontroller (let's ball park 10 meters for discussions sake). Should I be worried about an interference caused by running such long wires and are there any precautions or steps I can take to eliminate any complications? Thanks for the help in advance!

Offline Gertlex

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Re: Long wire interference
« Reply #1 on: December 09, 2011, 02:06:26 PM »
I've not delved into the theory or had to worry about it in practice, but from what I've read, twisted wire pairs work wonders http://en.wikipedia.org/wiki/Twisted_pair
I

Offline Soeren

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Re: Long wire interference
« Reply #2 on: December 09, 2011, 05:11:10 PM »
Hi,

Hi all. I'm currently working on a project that requires me to place a tactile switch a sizable distance away from my microcontroller (let's ball park 10 meters for discussions sake). Should I be worried about an interference caused by running such long wires and are there any precautions or steps I can take to eliminate any complications? Thanks for the help in advance!
For starters, twist the wires as Gertlex said (3..4 twists/inch) and keep the impedance as low as possible (i.e. make your pull up or- down resistor as low value as current drain allows).
Whether you'll need to do more is a question on the electrical environment it will be used in, but if you run into problems with the above methods in place, "current signalling" will only take a few extra components.
Regards,
Søren

A rather fast and fairly heavy robot with quite large wheels needs what? A lot of power?
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Offline adaschau2Topic starter

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Re: Long wire interference
« Reply #3 on: December 09, 2011, 05:18:51 PM »
Thanks for the tip Gertlex! And Soeren, I don't plan on using this in a very electrically "busy" area, so I'm not anticipating on running into too much trouble. Some more questions because I'm still new to this: Where can I get my hands on some cylindrical power connectors? I'm looking to buy a power supply like this (http://www.thaieasyelec.net/images/uploads/Product-Image/Power-Supply/EPWS013-5VDC.jpg) to power my circuit, but I can't seem to find the connector that I need. Tried searching for "male cylindrical connectors" and the like, but nothing seems to fit. Also, what exactly is "current signalling?"

Offline Soeren

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Re: Long wire interference
« Reply #4 on: December 09, 2011, 05:28:35 PM »
Hi,

Where can I get my hands on some cylindrical power connectors? I'm looking to buy a power supply like this (http://www.thaieasyelec.net/images/uploads/Product-Image/Power-Supply/EPWS013-5VDC.jpg) to power my circuit, but I can't seem to find the connector that I need. Tried searching for "male cylindrical connectors" and the like, but nothing seems to fit.
It's a regular "DC connector". Unfortunately, there are nearly endless combinations of inner diameter and outer diameter, so you need to know the exact measures of the one you need to mate - you can select from those measures at: http://dk.mouser.com/Search/Refine.aspx?N=1524918


Also, what exactly is "current signalling?"
Using current for the long stretch instead of voltage.
Regards,
Søren

A rather fast and fairly heavy robot with quite large wheels needs what? A lot of power?
Please remember...
Engineering is based on numbers - not adjectives

Offline adaschau2Topic starter

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Re: Long wire interference
« Reply #5 on: December 09, 2011, 05:31:26 PM »
Well if that just isn't the cat's pajamas! Thanks a million, that just saved me a long while of dithering around on the internet :)

 


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