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pulse generater and latching circuit

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Foulkesey

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Hi guys i am trying to create a circuit to override a trigger signal as in previous post https://www.electro-tech-online.com/threads/constant-voltage-on-latching-relay.144582/ i was originally wanting to use a dual coil latching relay but unsure if coil could handle constant voltage. The other problem was it was only pcb mounting and i require a simple installation. I have made another circuit with relay and capacitors to create a pulse and a single coil latching relay and wondered if you could cast your eyes over it and give me your opinions please. I have attached a photo of my design. Cheers joe
image.jpg
 
image.jpg
try again ...i will need a dual coil relay as i need a seperate switch and reset as the relay may recieve 2 x switch pulses before a reset, you will have to imagine the dual coil is all one piece as the program did not have one, cheers
 
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the relay may recieve 2 x switch pulses before a reset
How will that happen? With the circuit shown, the only way to get two 'set' pulses is to toggle the top-left switch. But that will give a 'reset' pulse after just one 'set' pulse.
 
How will that happen? With the circuit shown, the only way to get two 'set' pulses is to toggle the top-left switch. But that will give a 'reset' pulse after just one 'set' pulse.
The power is from the ignition therefore will go on and off without changing the switch, everytime the ignition turns on the pulse will generate from the relay from whichever position the switch is in. Hence the latching relay as i want the relay to stay in its last state after all power is off. Sorry my drawing doesnt show this i will try and claer it up a bit
 
Why are you using the top two relays ? Why not just put a capacitor in series with each winding on the latching relay. Also why use such a large value capacitor ? I would think a few hundred uF with a 100K resistor in parallel would give a long enough pulse to set or reset the latching relay. If there is any other load connected to the three position switch then you would also need to put a diode in series with each coil so that reverse polarity current does not flow though the coil when the ignition is switched off or the contact on the three position switch opens.
 
Why are you using the top two relays ? Why not just put a capacitor in series with each winding on the latching relay. Also why use such a large value capacitor ? I would think a few hundred uF with a 100K resistor in parallel would give a long enough pulse to set or reset the latching relay. If there is any other load connected to the three position switch then you would also need to put a diode in series with each coil so that reverse polarity current does not flow though the coil when the ignition is switched off or the contact on the three position switch opens.
Ok thanks Les i will redraw and id be greatful if u could have another look, i apreciate your help. Ive just been piecing together these parts and dont really know much about them Thanks
 
The diodes are in the correct position. (Any one of the 1N400x series will do.) The coils on the latching relay may need to be connected with the correct polarity. You will need to find the data on the relay. Try Googling the part number. I do not know how the switch works now you have added an extra contact. (I thought it was a single pole two way switch with centre off.) I was also under the impression that the "add on module" of which you have given no details would now be driving the mirrors rather than the switch.
 
Im planning on using omron g2rk-1 it only comes single pole, 2 way, nc or no. Im not sure if the module drives the mirrors (acesdvds qashqai mirror kit) but all i need is to block the central locking trigger to the module, so it does not fold the mirrors. I could of just put a switch in-line of the central locking trigger but i want it all to look original from the outside. So as it is i just need to correspond the right switch wire with the right coil. I know the coil needs a minimum pulse of 30ms so i will work out the capacitor and then i will buy/gather the parts and try it on the bread board. Thanks for your help Les il give u an update once i got it going. Thanks again!
 
I would change the 100K resistors for about 1K resistors. I originally chose a high value when your schematic showed that the circuit was permanently connected to the battery. This was to avoid the battery becoming discharged if the car was left unused for a long time.
 
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