Automotive Relay Connection

on an automotive system the relays are designed (usually) with the negative as a ground, using the entire car as that ground, so there really is no "switching" of the ground. what is your application? I'm guessing it isn't intended for a vehicle you just want to use some relays from a truck?

its a tracking device for trucks I want to use the relay for, it is suppose to bridge the two ground wire while the ignition is on and send information that ignition is on..

My suspicious and cynical nature has been stirred. This sounds much like an attempt to defeat the described device rather than install.

What do the printed instructions included with the tracking device have to say about this relay? We haven't heard from them, they probably know what to do.

It would be simpler to energise the device's positive wire from a place downstream of the ignition switch, thereby eliminating the need for a relay.

If you want wiring instructions we have to know what kind of system it is....brand name, model number....If this is something you are designing yourself we need to know what it is designed to do and how it works....If this is just a disabling device or just a timer or a multi-feature gizmo....any relay with a normally open and normally closed set of contacts would be able to perform this function....do you have the schematic for the relay?

It is something I ma designing for myself , its is to work as bridge between a ground wire and another wire(white wire).and then the circuit is closed with ignition on.. this is all I need.. this is my concern (the others I can send the information to device)

Why design it yourself. Just go into radio shack or any automotive store and purchase a 24 volt relay. The one you want is called a DPDT. Then you can wire in a bomb if like. Alternatively, you can take the voltage off the radio, and ignore the need for a relay.

is this a tricky question - i mean - what bloody diference does it make what the polarity of the wires you are bridging is when using a relay - ? bridging a connections ? - u can bridge the batteries in order to have greater load supported[br][br]if you bridge only the negative terminals - you don't have your cirquit closed - only a common ground - or other words you have - - tied (connected) the grids[br][br]
anywone? - is this guy using some other than logic "logic" white wire along whitch the negative wires are bridged - it's you like saying smth. and it actually doesnot say "something" - rather it generates a paradoxial state that opens up a pseudo "logic system" in whih uoy po re eta - confuse your human and get high to cloud share[br][br][br][br][br]? white wire = assigned spirit ? ? bridge 2 [s]similars[/s] same = force pseudo time into the realm of being here ??? 24V / 24h [br][br][br][br] old waters flow weird - muhahaa

actually it's a good one -- how to tell from a single point connection that the circuits have such ???

i guess it's even possible (that'hey've such )

this place CR4 forums is like a surprise egg - you never know which browser is willing to post your typings - besides i don't see the unsubscribe option from this disaster in account management

? why do they hire people for the job these people are not interested of ? perhpas there will be a new v. of browsers this forum thing suddenly will work with ... ? someday - so why to do anything

he wants a proving circuit, anyone capable of wiring in a GPS would find that childs play

Agreed, this is the easy part of the described project.

Hmmmmm... let's see... close a switch when the key is turned... what undefined other nefarious purposes could this possibly have?

BOOM

It doesn't sound like much of a problem.

Connect the relay coil to the ignition circuit (other side to ground of course). Cut the circuit you want to make/break and insert the relay connecting to the contact terminals. It doesn't matter whether the 2ndary circuit is at 0 volt or 24 volt or whatever.

There are any number of circuits that are energized when the ignition key is in the "run" position.

I see no need for any relays here, simply tap into an already existing circuit that energizes with the ignition key.

I'm beginning to share Doorman's skepticism on this.

Would that be LynDoor microwave-ready instant skepticism, at only $1.99 a pack from all good retail outlets, just add water?

Samples also available on-line, free of charge.

You are going to have to prove that to me.

Ah... another satisfied customer!

Sorry, I've been on a world wide tour of instant gratification delivery technology and have not been able to fulfill skepticism orders as quickly as we'd like.

Don't believe me, well.........................................................

I don't believe that either.

You don't believe that either?

It sounds like your order has already been delivered.

Dgoldwaters:

It sounds like a simple switch controlled by a voltage; when the ignition energizes the switch closes.

Bulky and expensive relays seem like over kill here.

It sounds like something someone with the most basic of electronics background could solve for a couple of dollars.

This is all I would have to offer until there is a clear understanding of the application.

I would also want to know the voltage between the ground and the other wire, the operating voltage, ampere load, or power consumption of the device being controlled.

Suggestion - send us a picture of the device you are trying to control.