Hello, I'm trying to switch a 12VDC relay for approx 500mS when the trigger voltage is removed but not when it's applied. I have searched on here and there doesn't appear to be any solutions that fit.
If it helps, what I'm aiming to do is simulate a button push on the central locking unlock button when the ignition is turned off, but not turned on.
If the switch is held for more than a couple of seconds, the system locks out and stores a fault code for a fault with the switch so I'm aiming for 500mS to allow for system voltage variance changing the duration slightly.
I've investigated a couple of ready-made modules, unfortunately these seem to hold the output active until the trigger is removed then start the timer.
The relay has a coil resistance of ~200 Ohms and a rated operating voltage of 12VDC, these relays tend to drop out below 10 - 10.5VDC. As well as the switched 12VDC, I obviously have a permanent 12VDC and ground. The switch i'm trying to simulate pulls the output down to ground, when the switch is open, the voltage from the central locking module is a nominal 12VDC. I'd rather use a relay to isolate the central locking module from any other system, as it is currently.
Thanks in advance for any help or guidance you may be able to offer, I'm quite handy with a soldering iron but circuit design is something I have little experience of.
If it helps, what I'm aiming to do is simulate a button push on the central locking unlock button when the ignition is turned off, but not turned on.
If the switch is held for more than a couple of seconds, the system locks out and stores a fault code for a fault with the switch so I'm aiming for 500mS to allow for system voltage variance changing the duration slightly.
I've investigated a couple of ready-made modules, unfortunately these seem to hold the output active until the trigger is removed then start the timer.
The relay has a coil resistance of ~200 Ohms and a rated operating voltage of 12VDC, these relays tend to drop out below 10 - 10.5VDC. As well as the switched 12VDC, I obviously have a permanent 12VDC and ground. The switch i'm trying to simulate pulls the output down to ground, when the switch is open, the voltage from the central locking module is a nominal 12VDC. I'd rather use a relay to isolate the central locking module from any other system, as it is currently.
Thanks in advance for any help or guidance you may be able to offer, I'm quite handy with a soldering iron but circuit design is something I have little experience of.