toggle switch question
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Forum Name: General Discussion
Forum Discription: General Mobile Electronics Questions and Answers
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=41398
Printed Date: April 28, 2024 at 12:28 PM
Topic: toggle switch question
Posted By: ty
Subject: toggle switch question
Date Posted: October 22, 2004 at 3:22 AM
I am planning on wiring a toggle switch to turn on/off my fuel pump, I bought a switch rated at 20 amps, however it is 125 volt AC, and 10 amps at 277 volt AC, is this ok to use for my configuration? Should I only use DC toggle switches in a car since the battery is 12v DC? Also I heard that the power is always in the top position, and the load is in the middle, so the top would be the wire that comes from my ecu right, and the load would be the other end of the wire that goes to fuel pump right? And what type of wire should I use for this setup, I was told by some to use speaker wire, and some said not to, what should I use? any help on this topic would be appreciated
Replies:
Posted By: MJA1962
Date Posted: November 04, 2004 at 8:14 AM
The switch you have is more than adequate for switching the fuel pump. I've never heard of any standard with regards to which terminal to use for power and load, but functionally, it makes no difference which wire goes to which terminal. As for the type of wire to use, it would be safe to match whatever is currently in use in the circuit you are switching. -Michael
Posted By: dxav
Date Posted: November 04, 2004 at 1:45 PM
Voltage is voltage, no matter Direct or Alternating. A 110VAC switch is fine for you application, as long as you are within current capacity.
Remember, it's not the volts that will hurt you -- it's the amps.
DXAV
Posted By: Teken
Date Posted: November 04, 2004 at 5:10 PM
Just wanted to add in a few things for your own reference.
Anytime you are interfacing with a *critical* electrical circuit. You should use a relay, as it will isolate the user from the circuit, and also allow a higher current capacity.
If the circuit is sensitve to inductive loads, it is wise, and suggested to add in a quenching diode to eliminate the CEMF (counter electro magnetic force).
Also, when switching any critical component such as the fuel pump, ECU, alarm CPU, only do so with a ground source.
If you insist upon switching a positive source, you will reduce the life span, or cause damage to the device in question.
Remember, switching ground starts the flow of electricty. Whereas, switching power, simply continues the intruppted flow of power.
ie. Voltage / current spikes, such as those created by black outs during bad weather.
Lastly, if the circuit wiring for the switch should short out, and you have live power flowing through the toggle switch, instead of ground. You will feel one hell of a shock.
With a switching ground source, the only thing that will happen is: Nothing
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Knowledge is power. But only if you apply that knowledge in a positive way, which promotes positive results in others.
EVIL Teken . . .
Posted By: jeffchilcott
Date Posted: November 07, 2004 at 12:52 AM
absolutly what I was going to say teken, but you beat me to it and also a little more in depth
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Posted By: Teken
Date Posted: November 07, 2004 at 1:07 PM
Just thought he should have all the information needed to make an informed decision. So as he can reap the benefits, without any potential hazards to him, others, or the vehicle.
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Knowledge is power. But only if you apply that knowledge in a positive way, which promotes positive results in others.
EVIL Teken . . .
Posted By: overworked
Date Posted: November 09, 2004 at 8:03 AM
just curious, why would you need to switch your fuel pump on and off?
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Posted By: Teken
Date Posted: November 09, 2004 at 4:03 PM
overworked wrote:
just curious, why would you need to switch your fuel pump on and off?
Typically with respect to automotive security it is used increase the level of protection for the user.
Many people use electronic ignition bypass methods. Others you electro mechanical in combination to electronic based immolbilizers.
ie. Using a switch, fuse, relay
It is all the concept of layering the vehicles security system with redundency and back-up.
------------- Knowledge is power. But only if you apply that knowledge in a positive way, which promotes positive results in others.
EVIL Teken . . .
Posted By: overworked
Date Posted: November 10, 2004 at 6:14 AM
I see Teken, my mistake I was under the impression that he wanted to switch the fuel pump off whilst running!?! WHere I got that idea from I don't know?
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