pulse switch?

Printed From: the12volt.com
Forum Name: Relays
Forum Discription: Relay Diagrams, SPDT Relays, SPST Relays, DPDT Relays, Latching Relays, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=98693
Printed Date: May 18, 2024 at 8:09 PM

Topic: pulse switch?

Posted By: mr.z
Subject: pulse switch?
Date Posted: November 06, 2007 at 12:22 PM

Hi all, probably in the wrong place but this seemed the best place..

what i actually want is this (but its in the states and I'm in the uk, it'd turn out very expensive to ship it over, a total of $40 probably)

https://www.aerostich.com/catalog/US/Autoswitch-p-16948.html

But it must be pretty straightforward to make one

It takes a 1second pulse from a 12-14v source and this switches on the output to fog lights for example.. a shorter pulse switches it off.. but a constant input has no effect (so you can leave your high beam on like normal withough it turning anything on/off)

(so useing the high beam you can switch on/off a device but unless you use a quick/slow pulse it does nothing)

Any ideas? could anyone help with a basic circuit design and ideas of the sort of components needed?

Thanks for reading

Replies:

Posted By: i am an idiot
Date Posted: November 06, 2007 at 3:41 PM

The following is a diagram for a Simple Latching relay. The on/off pulses are not time sensitive. One pulse turns it on and the next pulse turns it off. Short or long pulse, it doesn't matter. Pulse on then Pulse off.

Latched On/Off Output Using a Single Momentary Pulse

Similar to the momentary to constant configuration above, we can engage and disengage the latched output with a single pulse from a switch or an output from an alarm or remote keyless entry. The first pulse from the switch will engage the latch. The next pulse from the switch will disengage the latch.
posted_image

Posted By: mr.z
Date Posted: November 06, 2007 at 6:18 PM

wow! thats teriffic!

I do have a bunch of mini relays so that would take up a fair bit less space..

i see theres a variation that can be done without diodes? what type of diodes would be used if i did go that way? (or just big as you can get?)

One thing, with relays some wires aren't really carrying any real ampage (the two that are switching) which ones would they be on here?

Would it be the red and the blue needing the meatyer 18amp wire and the rest ok with smaller 5amp stuff? or am i missing something?

Thanks very much for the reply :D