How to Wire/make a time delay power on switch - Page 1
Forum section: electronics / beginners

author: marmono
author_rank: Newbie
timestamp: August 20, 2019, 05:55:39 pm
content: What I need to accomplish: I am building an arcade using a windows pc and I want to hide all traces of windows and the fact that its a pc. Hiding windows isnt an issue using windows 10 enterprise so I have that covered, but there is no way to get rid of the branded dell logo plastered bios screen. I am going to wire a momentary switch that powers on the lcd,pc,lights etc. all on one switch. What I would like to happen is that I hit the switch, the pc immediately powers up and then there is a 10 second delay before the lcd powers on. This would accomplish what im trying to do as the bios screen would have already passed before I get picture to the lcd.Im sure there is SOMETHING or some way to accomplish this, but I dont know the terminology of the part Im looking for. Can someone steer me in the right direction?

author: dcbrown73
author_rank: Regular Contributor
timestamp: August 20, 2019, 05:59:23 pm
content: I haven't worked on Dell PCs in years, but I know some BIOS allow you to do a fast boot that pretty much bypasses the splash screen and boots immediately.Does the BIOS not give you this option?

author: ledtester
author_rank: Super Contributor
timestamp: August 20, 2019, 06:05:33 pm
content: If you can wait awhile, just buy a "timer relay" on ebay/aliexpress/amazon.Or google "555 timer relay circuit".

author: marmono
author_rank: Newbie
timestamp: August 20, 2019, 06:09:45 pm
content: good call, but no, I do have fast boot turned on and while this does make it load faster the dell bios screen still displayed. As far as my research can tell there is no way to eliminate the post screen loading brand and load animation

author: marmono
author_rank: Newbie
timestamp: August 20, 2019, 06:15:54 pm
content: Quote from: ledtester on August 20, 2019, 06:05:33 pmYes that seems like exactly what im looking forThe only thing im wondering about is, the device seems like it sends voltage, I want to power on an lcd so I dont want to send any voltage input I just want it to close the circuit between the two pins on the lcd that power it on.

author: ledtester
author_rank: Super Contributor
timestamp: August 20, 2019, 06:21:54 pm
content: A relay just completes a circuit like a switch.The module has three "output" pins... COM, NO, and NC on one side of the board.Normally the relay connects NC and COM together. 10 secs (or whatever you set the delay time to) after power is applied to the Vcc and GND pins on the other side of the board the relay is energized and connects NO and COM.The video uses the module to control an mains powered lamp, but you can use it for low voltage circuits too.

author: marmono
author_rank: Newbie
timestamp: August 20, 2019, 06:30:18 pm
content: Thank you for your help. That does sound like it would work but the momentary switch is just an open and close so I technically would not be supplying ANY voltage to it via the actual button press, nor would the device be supplying voltage to the lcd, that being the case do you think the device could be made to work in this way?

author: ledtester
author_rank: Super Contributor
timestamp: August 20, 2019, 06:42:50 pm
content: Maybe this is better for your application:http://www.learningaboutelectronics.com/Articles/555-timer-delay-before-turn-on-circuit.phpReplace the LED with a relay.

author: marmono
author_rank: Newbie
timestamp: August 20, 2019, 07:46:19 pm
content: Quote from: ledtester on August 20, 2019, 06:21:54 pmyou have given me an epiphany and I think you have solved my problem....I can connect the original switch module I linked to the 12v rail of my PC power supply, once the PC is powered on it provides 12v to the device, I connect NO and COM to the power on pins of the lcd and Bobs your uncle...