Coldbreak Brewing HERMS Giveaway!

HomeBrewSupply AMCYL Brew Kettle Giveaway!


Home Brew Forums > Home Brewing Beer > Electric Brewing > Actuating valves using rotary switch + diodes?
Reply
 
Thread Tools
Old 05-13-2012, 01:11 AM   #11
passedpawn
Waste Allocation Load Lifter - Earth Class
HBT_MODERATOR.png
Feedback Score: 1 reviews
 
passedpawn's Avatar
Recipes 
 
Join Date: Apr 2009
Location: ☼ Clearwater, FL ☼
Posts: 22,052
Liked 4836 Times on 2890 Posts
Likes Given: 4052

Default

Quote:
Originally Posted by emjay View Post
Thank you. Now I just need to figure out what type of diode is most appropriate, and whatever the particular specs I need.

Does running current backwards across an LED ruin it? I may just use LEDs if I can maintain enough voltage to the valves, and give myself a nice little indicator diagram.
An LED is a diode and will only conduct in one direction. They can withstand a reverse voltage (i.e., cathode is higher than the anode) up to a certain point, at which they will break down and become a short circuit (or open circuit).

Most LEDs are rated for under 50mA continuous current. Over that, they burn. I'm sure your application requires more than that amount of current, so that won't work for you.

Probably the most common diode is the 1N4001. It will run you 8 cents, you can probably get them at rat shack. It's a 1A diode.


__________________
- Andrew
passedpawn is offline
 
Reply With Quote
Old 05-13-2012, 01:51 AM   #12
emjay
HBT_SUPPORTER.png
Feedback Score: 1 reviews
Recipes 
 
Join Date: Jan 2011
Location: Toronto, Ontario
Posts: 12,712
Liked 1716 Times on 1604 Posts
Likes Given: 1

Default

Quote:
Originally Posted by passedpawn

An LED is a diode and will only conduct in one direction. They can withstand a reverse voltage (i.e., cathode is higher than the anode) up to a certain point, at which they will break down and become a short circuit (or open circuit).

Most LEDs are rated for under 50mA continuous current. Over that, they burn. I'm sure your application requires more than that amount of current, so that won't work for you.

Probably the most common diode is the 1N4001. It will run you 8 cents, you can probably get them at rat shack. It's a 1A diode.
Yeah I know LEDs are diodes, hence my idea. But my valves supposedly draw 45-100mA, and it will only be a single valve to each diode, so I wonder if any LEDs that can handle that.

So given the current, and that it'll be 12 volts, you think that the 1N4001 will suffice? If so, my only concern is that the voltage drop isn't too high for the valves to function properly.
emjay is offline
 
Reply With Quote
Old 05-13-2012, 03:16 PM   #13
crane
Feedback Score: 0 reviews
Recipes 
 
Join Date: Sep 2011
Location: San Diego, CA
Posts: 424
Liked 50 Times on 41 Posts
Likes Given: 1

Default

The forward voltage drop for the 1N4001 is 1.1V so your valves would get 10.9V. This should work but you need to check the datasheet for your valves for the minimum voltage to turn them on.
crane is offline
 
Reply With Quote
Reply


Thread Tools



Forum Jump

Newest Threads

LATEST SPONSOR DEALS