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120v Timer Circuit Help

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#1 auto-logic

auto-logic

    Neowinian

  • Joined: 06-July 04

Posted 05 March 2014 - 19:16

I need a little bit of help building a timer circuit and here's to hoping someone on the board can advise.

I need to:
Press a button
Have that activate a timer circuit which will supply power to a 120v outlet for around 10 seconds and then kill it.

 

Can anyone point me in the direction of prebuilt or DIY circuits for this kind of thing?

Thanks!



Best Answer Astra.Xtreme , 05 March 2014 - 19:26

Well the easy way is to use a solid state timer relay.  Typically relays like that are rated for something around 24V~220V and the timer is adjustable, so you'll have a lot of flexibility.

 

Here's an example:

http://www.digikey.c...1178-ND/2828022

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#2 Aheer.R.S.

Aheer.R.S.

    I cannot Teach Him, the Boy has no Patience!

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  • Joined: 15-October 10

Posted 05 March 2014 - 19:19

Should be easy to source those parts from any electronics store...

(Maplins, etc...?)

 

You need a 'Push to make' button, a timer chip with an adjustable screw, a relay switch, wire and some sort of board

(we used to make stuff like this in school, so maybe someone in school or a friendly teacher would help)



#3 OP auto-logic

auto-logic

    Neowinian

  • Joined: 06-July 04

Posted 05 March 2014 - 19:23

Should be easy to source those parts from any electronics store...

(Maplins, etc...?)

 

You need a 'Push to make' button, a timer chip with an adjustable screw, a relay switch, wire and some sort of board

(we used to make stuff like this in school, so maybe someone in school or a friendly teacher would help)

Thank you for the reply:

My biggest concern is how to run 120v in and out of this safely.



#4 Astra.Xtreme

Astra.Xtreme

    Electrical Engineer

  • Tech Issues Solved: 5
  • Joined: 02-January 04
  • Location: Milwaukee, WI

Posted 05 March 2014 - 19:26   Best Answer

Well the easy way is to use a solid state timer relay.  Typically relays like that are rated for something around 24V~220V and the timer is adjustable, so you'll have a lot of flexibility.

 

Here's an example:

http://www.digikey.c...1178-ND/2828022



#5 Aheer.R.S.

Aheer.R.S.

    I cannot Teach Him, the Boy has no Patience!

  • Tech Issues Solved: 9
  • Joined: 15-October 10

Posted 05 March 2014 - 19:29

Sorry, forgot to add something..

 

For the concern running the 120 volts, the relay is key, if you can get one that can internally take the wiring for the 120 volt supply, it should be safe, as the relay shouldn't feedback to your push button circuit..

if, for some reason, you cannot find such a relay, then you'll need a qualified electrical engineer as the circuit becomes more complicated,

and a second apology, the advise for a qualified electrical engineer should have been my first response



#6 OP auto-logic

auto-logic

    Neowinian

  • Joined: 06-July 04

Posted 05 March 2014 - 19:32

Well the easy way is to use a solid state timer relay.  Typically relays like that are rated for something around 24V~220V and the timer is adjustable, so you'll have a lot of flexibility.

 

Here's an example:

http://www.digikey.c...1178-ND/2828022

 

That's great. Thank you!

I'll mark this as solved but if you have any input if the below would be suitable, I'd appreciate it.

 

http://www.grainger....nCode=P2IDP2PCP

 

Best



#7 Astra.Xtreme

Astra.Xtreme

    Electrical Engineer

  • Tech Issues Solved: 5
  • Joined: 02-January 04
  • Location: Milwaukee, WI

Posted 05 March 2014 - 19:38

That's great. Thank you!

I'll mark this as solved but if you have any input if the below would be suitable, I'd appreciate it.

 

http://www.grainger....nCode=P2IDP2PCP

 

Best

That will definitely work.  I don't know what sort of footprint you need this to be in, but you could alternatively get one that can be mounted to a DIN rail, and also probably find a button that can be DIN rail mounted.  Mounting and wiring will be quite a bit easier that way.

 

http://www.grainger....nCode=P2IDP2PCP



#8 OP auto-logic

auto-logic

    Neowinian

  • Joined: 06-July 04

Posted 05 March 2014 - 19:42

That will definitely work.  I don't know what sort of footprint you need this to be in, but you could alternatively get one that can be mounted to a DIN rail, and also probably find a button that can be DIN rail mounted.  Mounting and wiring will be quite a bit easier that way.

 

http://www.grainger....nCode=P2IDP2PCP

 

Awesome. Thank you, and the DIN rail may be a good option as well, which I wasn't even aware of.

Much appreciated. :D



#9 nelsontb

nelsontb

    Neowinian

  • Joined: 20-May 13

Posted 05 March 2014 - 19:47

you can use a  staircase lighting timer, any electrician can help you with that but it may be difficult to find one with so low ON time

 

from the first page i found on Modular Timers