Adjustable Pulsing Ground

[Csnead]

Hello all,

I have a project I would like to do, and I think it should be fairly simple to accomplish, but my googling has not led me to an answer. Basically I want to develop a switch that will pulse.

Here is the basic operation:

A simple momentary button will activate it
when this button is NOT pressed, the switch will simply be a normally closed circuit
When the user presses and holds the button, the switch will pulse open until the user releases the button.
This pulse will be adjustable.

For example, the circuit is closed and working normally, the user holds the button, the switch goes open for .001 second, then closed for .100 second, open for .001 second... etc. then the user releases the button and the switch goes closed completely again.

The switch will be used by a 12V DC battery. It should see at the very most around 30 amps.

Any help would be great!

Thanks,
Clinton

 

[(*steve*)]

This could be accomplished with a 555, held in reset until the button is pressed, then running in an astable mode at 500Hz. This would need to switch a pretty heavy duty mosfet, possibly via a gate driver.

What is the load you're switching? 30A is a lot to be turning on and off if there is an inductance. You'll almost certainly need some protection from voltage spikes as you turn the mosfet off and possibly current spikes as you turn it on.

 

[Csnead]

Just after I posted, I was thinking the same thing about the 30 Amps. I am not able to figure out the actual load right now, so I was just going off of information from the device I am attempting to make myself.

Here is the link to what I am trying to do:

http://www.moretraction.com/Products_Bump_Box.htm

Thanks,
Clinton

 

[(*steve*)]

I read that page and I am still completely unsure about what this device does. (I'm also posting from my phone, I'll look at the video later).

See if you can find out more about the load.

 

[Csnead]

I have dug a little deeper and found out some more information. This device will be pulsing one of these solenoids. According to the manufacturer's information, the max current is 8 amps at 12.5 volts.

Hopefully that will help!

 

[KrisBlueNZ]

You may not get any more help with this project here, because it's clear that it's an automotive modification. Some sites, and some users, avoid these projects because of the inherent dangers. If something were to go wrong, and someone was injured or killed, even if no one tried to blame it on advice given here, we would feel awful just to have been involved.