Delay circuit with remote push button - Page 1
Forum section: electronics / beginners

author: rad400
author_rank: Contributor
timestamp: December 23, 2015, 04:42:50 pm
content: I am looking for a circuit board, that when activated by a remote push button switch, the circuit board will activate a relay for a set period of time, allowing a 18 volt device to operate and the circuit board will turn off after a set period of time. Whenever the remote push button is pushed, the on & off cycle of would repeat on the circuit board. I found a circuit board on eBay (See below) which provides what I want, but the push button is located on the device. I need to have a circuit board where I have connections for a push button, so I can located a push button remotely.Any sugestions?Thanks,RAD400http://www.ebay.com/itm/321596539805DC 12V timer relay module , Attracting and disconnect delay relay up to 1 hour

author: Simon
author_rank: Unknown
timestamp: December 23, 2015, 04:47:45 pm
content: Are you talking wired remote or wireless. Can you solder your own wires on in parallel with the button to put your own button on ?

author: rad400
author_rank: Contributor
timestamp: December 24, 2015, 03:08:20 pm
content: It will be a wired connection and I have looked at trying to connect an external switch to the circuit board, but the switch connections on the board are under the switch and the circuit board is a multi layer board, so I can't get to the underside of the switch connections on the board.Basically what I am looking for is device similar in many toys, which allows you to push a button on the toy and the toy will function for a set period of time and then turn off.Thanks RAD 400

author: Simon
author_rank: Unknown
timestamp: December 24, 2015, 03:13:17 pm
content: how long do you need it to work for ? a 555 might be able to do it or a micro controller.

author: rad400
author_rank: Contributor
timestamp: December 24, 2015, 03:18:55 pm
content: under a minute, 30 to 60 seconds. I have seen 555 timers, but not sure how to hook them up. I was trying to get the timer, relay, connectors, etc all on the same board already made but will look at alternatives..

author: Simon
author_rank: Unknown
timestamp: December 24, 2015, 03:27:07 pm
content: so do you want to buy something ready made or are you prepared to make it yourself ?

author: alsetalokin4017
author_rank: Super Contributor
timestamp: December 24, 2015, 04:40:39 pm
content: @rad: I can understand the fact that a premade unit could be easier to work with for you, but there are certain advantages to doing it yourself, too. You will learn a lot more and you'll have a great deal of satisfaction when you have done it yourself.The basic circuit you need is called the 555 monostable multivibrator circuit.By coincidence another poster has been building this circuit in another thread, and I happen to have it breadboarded in front of me now. With the component values I'm using the circuit runs on 5v and lights up an LED for the desired time for about 5 seconds. I've changed one component (the 10 k timing resistor, change to 100 k) and now the circuit lights up the LED for about 50 seconds. By putting in a 100 k variable resistor (trimpot) here instead you can set the on-time from a few seconds up to over 50 seconds. Now, instead of the original NPN transistor I have put in a mosfet, which substitutes for the relay. By changing one more resistor value ( the LED current-limiting resistor) it can run on 12 volts instead of 5v. The entire thing would probably cost less than the board from Ebay ($5.30 delivered) if you built it on a self-made hardwired "breadboard".It uses:1 555 timer chip5 1/4 watt resistors (or 4 resistors + 1 trimpot)2 10 nF capacitors1 470 uF capacitor1 BC337-25 transistor1 LED1 pushbutton switch, momentary ON typeTo make it useful for switching an external circuit:1 power mosfet like IRF3205 instead of the BC337-25 transistor2 2-pin connectors (one for power, one for external device)Here the circuit as I've described it (IRF3205 mosfet) is controlling a 12 volt automotive brake light bulb drawing 2 amps. It stays on for 54 seconds, using 100K and 470uF for the timing components:

author: rad400
author_rank: Contributor
timestamp: December 24, 2015, 06:01:28 pm
content: Quote from: Simon on December 24, 2015, 03:27:07 pmSimonFor this project I would prefer to purchase already made, similar to the device in my original post. I will need 8 of the units and will need to slightly vary the time on each one to match up with one full cycle of operation of the item I am powering. The items I want to power are 12-18V toy carnival rides.RAD400

author: rad400
author_rank: Contributor
timestamp: December 24, 2015, 06:07:16 pm
content: Quote from: alsetalokin4017 on December 24, 2015, 04:40:39 pmalsetalokin4017Thanks for the information on how to build one, but for this project I would prefer to purchase already made, similar to the device in my original post. I will need 8 of the units and will need to slightly vary the time on each one to match up with one full cycle of operation of the item I am powering. The items I want to power are 12-18V toy carnival rides.Thanks,RAD400

author: Simon
author_rank: Unknown
timestamp: December 24, 2015, 07:06:34 pm
content: You want 8 units ? so what exactly does your project entail ?

author: rrinker
author_rank: Super Contributor
timestamp: December 24, 2015, 07:35:08 pm
content: Sounds like maybe part of a model railroad? If all 8 rides are in close proximity, a micro and an 8 relay board, plus 8 push buttons and pull-up resistors and you're all set.

author: Simon
author_rank: Unknown
timestamp: December 24, 2015, 07:39:56 pm
content: That is what I was thinking

author: SL4P
author_rank: Super Contributor
timestamp: December 24, 2015, 07:52:24 pm
content: Quote from: rrinker on December 24, 2015, 07:35:08 pmVoila!I made these a few years ago for a completely different application.• INPUTS• Four independent TTL level inputs. Contact closure to 0V.• Input threshold approx >3.5mA or <200-ohms closed circuit.• Individually configurable for normally-open or normally-closed (default) operation.• Two temperature probe inputs -50 / +120C (optional / special order)• DELAY PERIODS• Input delay individually configurable for each input, between immediate and 20 minutes, in 15 steps.Custom delay periods may be requested.• OUTPUT• Relay may be configured for N/O, (or active N/C operation to raise upstream alarms).• Relay On/Off durations may be set between 0.2s and 30 secs in 15 steps for each input.Custom on and off periods may be requested.The lowest numbered input takes output priority.Relay modes of operation:o STEADY ON for duration of input event.o ONE-SHOT ON then stays off until retriggered.o REPEATING ON-OFF CYCLE as long as input is asserted.• POWER SUPPLYo 8-24V DC <200mA with all inputs closed, and relay on.o Input polarity protected.

author: Muttley Snickers
author_rank: Unknown
timestamp: December 24, 2015, 08:56:22 pm
content: Not sure if anyone has seen these programmable relays linked below, we have used them many times and I have a couple here if anybody needs some information, I cant post the PDF but the link will get you there.http://www.smartinnovations.com.au/