Thread: is there something that can sense off and on ignition?

In the power supplies section of the FAQ, this will be answered.

If it´s a standard ATX board your trying to power, my suggestion is an opus. They´re [all] usually selectable for pre-defined startup and shutdown timers that can be adjusted, the amount and duration is just limited by what they´ve set the micro-controller for each to be able to do. Opus seems to have better options where this is concerned, at least in my limited experience.

My opus 360 for example I have set to run 15mins after the ACC line (or IGN if you want to use that) is cut. And starts 5 seconds after power is supplied (steady) to ACC, with a higher than usual undervolt setting for actual startup (not counting the cut-off setting), so it doesn´t come on unless the battery is at a certain level even if power is sensed on the ACC line.

just read the reviews, and forum section of the power supply your considering before buying.

also just wanted to add after answering your other question about prebuit/used/diy:
the faq is a great resource that covers many of the common questions-- i was going to post the link, but seeing as wayne did, no need to..

actually i just built something that this for another forum member
where the post is i have no idea.. ill try to find

If you have a DC powered board Carnetix is the way to go.

Originally Posted by cockie55

If you have a DC powered board Carnetix is the way to go.

You mean a board that accepts a single DC voltage.

All motherboards are DC-powered.

This is the link mitch was talking about:

Interest Feeler: Simple Power Controller

as it says the controller is rather simple... when acc goes high it first turns on the pc then amps... big relay takes 16A and small one 1A should be enough for most peeps

at acc off it waits about 20 secs then cuts power

i'm still testing at tweaking the code in the PIC controller... at the moment it powers up ok but there is no delay at power off... new code is going to be tested in the weekend

upps

forgot to say about the price.... i paid mitch to make it pro with a box.. the rough schematic was something i found and put together and he then revised it and made a few improvements

as i remember (might be wrong) i paid 90$ for 5 boards and about 20$ for parts for 2 of them

i have both of them but only one is in use... the spare one only need 2 connectors for power input and output...

so there are plenty of options to get a few.... but let me test the new code first

and mitch also have made an io box that can tell the pc to power off when acc goes low

stay tuned

Controller is up and running. Programming it is very simple, you only need a serial cable from mitch and http://www.rev-ed.co.uk/software/bas805.exe

I had some issues that caused the controller to cut power at acc off no matter what. My fault was a relay coil that injected spikes at the acc input, causing the picaxe chip to reset and cut power instantly.

Mitch made a program for it, but a more simple program could look like this, its intended for those not so sharp on programming:

Code:

#REM Simple Power Controller V.1.0

*******************************************************************************
********************** Program Size 35 out of 256 Bytes ***********************
*******************************************************************************

#ENDREM

Start:				;Main program start

Symbol T = B4			;Used to check if pc powered up
T=0

setint %00000000,%00001000 	;Go straight to interrupt when pin3 goes low ie when 12V is applied, no matter what
		
Main:					
	if t = 0 then main
	if pin3 = 0 then main	;If acc is on then stay here
	Wait 20
	Low 1
	Low 2
	
goto Start				;Goto start 
	
Interrupt:
	
	Wait 5
	High 1
	Wait 20
	High 2
	T=1
	return				 ;Goto main program loop and continue

wait 5 is the delay from acc on to pc is powered, i have this set to 3... its just enough for things to get stable after cranking. next wait 20 is the time until amps are powered. Remember this is also counted from the start, so its 15 secs after pc in the above code.

they way the code work:

• T is defined as ram area B4, this is used to check if pc has been powered.
• T is set to 0 so the program knows pc is not powered yet.
• Interrupt is set, it tells the pic to go to the interrupt section no matter where in the program the pic is. This happens when acc input goes logic low. The input is pulled high when acc is not high, effectively this makes the input inverted.
• As T is 0 the next line tells the pic to stay at start of main program loop.
• When acc is high the Pic jumps to the interrupt section and first turn on pc then amps and sets T to 1 so the pic knows stuff are powered.
• Pic then jumps back to where it left of at the main program loop.
• The pic now jump to the next line thats says if acc input is 0 it should stay there, but if we turn off acc then the input will go 1 and the 20 sec wait until power off is started. After that everything start over.

this does not take in to account if the user changes mind before the 20 secs. This could be done by inserting:

if pin3 = 0 then main

just before the 2 low commands. I have skipped this myself since cranking will pull supply so low everything restarts.

One would ask why not use a carnetix then... Well this controller is suited my purpose and is as dirt cheap to build as i'm cheap when it comes to reaching in to my pocket.

if interested in a controller pm me or mitch.. me if you live in the EU