Haynes Forums  

Go Back   Haynes Forums > Haynes Roadster Forums > Electrics
FAQ Members List Calendar Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Display Modes
  #1  
Old 15th November 2014, 10:38 PM
thailoz thailoz is offline
Senior Member
 
Join Date: Mar 2013
Location: Thailand
Posts: 140
Default One for the electrical gurus........auto switch off

I have an Idea but not sure how to go about it

I want to have some of my switches auto reset when ign is off.. for example :-

Fuel pump circuit

What I would like is when the ign is on I could push a momentary on button which will then switch power to my fuel pump also lighting an ind lamp telling me I have power.
Then when switch the ign off the switch resets ,so that every time you get in the car you have to push the button to start the car (sort of security device if you like).

So can any one shed any light on how to do this please.

Laurence
__________________
My build diary is at http://thailoz.wordpress.com/
Reply With Quote
  #2  
Old 15th November 2014, 11:36 PM
davedew's Avatar
davedew davedew is offline
Senior Member
 
Join Date: Jul 2010
Location: Taunton
Posts: 342
Default

I would have thought if you used a latching relay that was fed from an ignition switched feed would do this.

Turn ignition on to provide power. Momentary push switch to earth relay and activate.
Turn ignition off, relay looses power and resets.
__________________
http://s831.photobucket.com/user/dav...ter%20Pictures

OTR 01/05/14 - 1.6 CVH, Type 9, Bike Carbs, Megajolt
Reply With Quote
  #3  
Old 16th November 2014, 01:19 AM
thailoz thailoz is offline
Senior Member
 
Join Date: Mar 2013
Location: Thailand
Posts: 140
Default

Maybe ive answered my own question

would this work I dont have any relays at the moment to test it




any comments or additions greatly appreciated
__________________
My build diary is at http://thailoz.wordpress.com/
Reply With Quote
  #4  
Old 16th November 2014, 08:32 AM
SeriesLandy's Avatar
SeriesLandy SeriesLandy is offline
Senior Member
 
Join Date: Nov 2008
Location: Portsmouth
Posts: 828
Default

You could do this with a 4 or 5 pin relay.
I'm assuming that you want to be able to switch the fuel pump off (hidden switch for security?)
If you were going to use the 5 pin, what is the purpose of the link between pin 86 and 87? All that does when the relay is active is feed the power back to pin 30.
__________________
Steve
My Photo Album | Haynes Roadster FAQ | IVA Forms How To

Last edited by SeriesLandy : 16th November 2014 at 01:14 PM.
Reply With Quote
  #5  
Old 16th November 2014, 04:29 PM
Stot's Avatar
Stot Stot is offline
Senior Member
 
Join Date: Nov 2012
Location: Wolverhampton
Posts: 748
Default

The link from 87-86 would provide live to the coil only after the momentary switch had been pressed once and while the ignition is still switched on. Turn off ignition and you need to press the switch again to power the fuel pump.

It would work however you have fuel Pump - on your diagram and that system would provide fuel pump +

Cheers
Stot
__________________
1.6 Mazda B6 : Garrett TBO339 : 420cc WRX Injectors : FMIC : Microsquirt V3 : LC-2 Wideband : Toyota COP
Build Started Jan 2013 : OTR Aug 2014 : Build Pictures
Reply With Quote
  #6  
Old 16th November 2014, 05:09 PM
SeriesLandy's Avatar
SeriesLandy SeriesLandy is offline
Senior Member
 
Join Date: Nov 2008
Location: Portsmouth
Posts: 828
Default

Now stot has explained it, yes it would work. I didn't realise that that was a momentary switch.
__________________
Steve
My Photo Album | Haynes Roadster FAQ | IVA Forms How To
Reply With Quote
  #7  
Old 16th November 2014, 07:02 PM
Stot's Avatar
Stot Stot is offline
Senior Member
 
Join Date: Nov 2012
Location: Wolverhampton
Posts: 748
Default

Depending on the reasoning behind a fuel pump relay here is a diagram showing the way I ran the fuel pump on my old carbed crossflow car.



Turning on the ignition would energize the coil meaning that to get power to the fuel pump you had to be cranking the engine. Once the engine starts the oil pressure has built and the coil de-energises supplying power to the fuel pump from IGN live. If the engine stalls or you lose oil pressure for some reason the coil energizes and the fuel pump will stop again until you crank it again.

Cheers
Stot
__________________
1.6 Mazda B6 : Garrett TBO339 : 420cc WRX Injectors : FMIC : Microsquirt V3 : LC-2 Wideband : Toyota COP
Build Started Jan 2013 : OTR Aug 2014 : Build Pictures

Last edited by Stot : 16th November 2014 at 07:26 PM.
Reply With Quote
  #8  
Old 16th November 2014, 07:27 PM
flyerncle flyerncle is offline
Senior Member
 
Join Date: Mar 2008
Location: gateshead,near cobbly bit of A1 North
Posts: 3,188
Default

Many years ago we used to service a fleet of vehicles that was imobilised until you touched a screw or other point that was connected to the imobiliser and the ignition barrel metal,brilliant idea if you did not know it was there,unknown as to who made it.
__________________
Cost : Little as possible.
Thanks : To those who by their generosity my build has progressed.
Its a handmade sports car not a flaming kit car !!!


If at first you dont succeed,avoid skydiving...

No parachute require to freefall,only if you want to do it twice.
Reply With Quote
  #9  
Old 16th November 2014, 08:58 PM
thailoz thailoz is offline
Senior Member
 
Join Date: Mar 2013
Location: Thailand
Posts: 140
Default

thanks for the replies. I am after putting a hidden switch for the fuel pump.Would I need a second relay for the pump using the relay in the diagram as a trigger?
__________________
My build diary is at http://thailoz.wordpress.com/
Reply With Quote
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT +1. The time now is 08:57 AM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2020, Jelsoft Enterprises Ltd.