diode protected relay

Home / the12volt's Install Bay / Car Audio / diode protected relay (

Topic Closed)

Welcome Guest :)

Members

Next Page > < Prev Topic Next Topic >

y2j514

Copper - Posts: 94

Joined: April 26, 2007

Location: Quebec, Canada

Posted: January 16, 2010 at 5:56 PM / IP Logged

Ok so I want to use a relay on my remote wire from my HU to turn on my amplifiers and a few fans. I want to diode protect the relay to avoid the voltage spike that happens with the instant flicking of the coil.

I know you must place the diode across the relay with the cathode (striped side) facing the positive side of the coil. I am just wondering what rating of a diode I need?

I have a 15 volt 1/2 Watt diode lying around - any good?

Thanks

i am an idiot

Platinum - Posts: 13,671

This member consistently provides reliable information

Joined: September 21, 2006

Location: Louisiana, United States

Posted: January 16, 2010 at 6:13 PM / IP Logged

Do not use a Zener diode. With the rating you gave, that appears to be a Zener. You need a 1N400X, where X is any number from 1 to 7

y2j514

Copper - Posts: 94

Joined: April 26, 2007

Location: Quebec, Canada

Posted: January 16, 2010 at 6:17 PM / IP Logged

You're absolutely right. It is a Zener diode. Thanks for the input. If you don't mind, otherwise I can just google it, what exactly is the difference between these 2 diodes?

i am an idiot

Platinum - Posts: 13,671

Joined: September 21, 2006

Location: Louisiana, United States

Posted: January 16, 2010 at 6:29 PM / IP Logged

Description of diode at the top of the following page. Zener diode description about 1/3 way down the page.

http://www.bcae1.com/diodes.htm

y2j514

Copper - Posts: 94

Joined: April 26, 2007

Location: Quebec, Canada

Posted: January 16, 2010 at 6:45 PM / IP Logged

Thank you. So since I have to go out and buy a diode - do you recommend one more than the other? In terms of X being 1 to 7.

i am an idiot

Platinum - Posts: 13,671

Joined: September 21, 2006

Location: Louisiana, United States

Posted: January 16, 2010 at 7:05 PM / IP Logged

The 4001 is rated at 50 volts, the others are rated at higher voltages. For automotive applications none will be any better than the other. Whatever you can find will work.

oldspark

Gold - Posts: 4,913

Joined: November 03, 2008

Location: Australia

Posted: January 17, 2010 at 2:51 AM / IP Logged

The 1N4004 (400V) seems to be the most common with 4007 (1000V) close by - the others seem to have bee dropped (at least here under).

Usually 200V or higher is chosen for automotive applications...

y2j514

Copper - Posts: 94

Joined: April 26, 2007

Location: Quebec, Canada

Posted: January 17, 2010 at 2:46 PM / IP Logged

Ok, so I've been doing some reading around and I'm worried that the fans will make too much noise when I play the music at a quieter level.

I know using a thermisistor is possible - although even using bcae1 I have no idea how to do it. I can follow the logic pretty well - I just cant 100% read the diagram on bcae1.

I doubt this is an option but is there a way to simply make the fans spin faster as the volume increases? Like using an splicing an RCA cable from the HU or something?

i am an idiot

Platinum - Posts: 13,671

Joined: September 21, 2006

Location: Louisiana, United States

Posted: January 17, 2010 at 7:14 PM / IP Logged

The wire labeled to active speaker terminal connects to a bridged speaker wire of a multichannel amp, or the positive terminal of a mono amp.

http://www.bcae1.com/temp/speakerlevelfancontroller01.gif

Save the image to your harddrive. I have no idea how long it will stay on his server.

i am an idiot

Platinum - Posts: 13,671

Joined: September 21, 2006

Location: Louisiana, United States

Posted: January 17, 2010 at 7:16 PM / IP Logged

diode protected relay -- posted image.

All parts are available at Radio Shack. The 6 or 7 digit numbers are radio shack part numbers. The resistors are 1/4 watt or 1/2 watt. whatever they have in stock. The cap should be 16 volts or higher.

Next Page >

Printable version

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot delete your posts in this forum
You cannot edit your posts in this forum
You cannot create polls in this forum
You cannot vote in polls in this forum

Search the12volt.com

Follow the12volt.com

Disclaimer: *All information on this site ( the12volt.com ) is provided "as is" without any warranty of any kind, either expressed or implied, including but not limited to fitness for a particular use. Any user assumes the entire risk as to the accuracy and use of this information. Please verify all wire colors and diagrams before applying any information.