two closed going open contacts from one

[kevmac72 0]

i have a pir which gives a closed going open contact. My problem is that i need two independant outputs to trigger two devices. when i loop through both devices - throught the closed going open, only one will trigger. Does any one know of a solution which preferably does not use power.

[scorpion 0]

The two device that are being controlled, do they activate what they are supposed to do with an open to the input?

 

Alarm panel are ok with the closed circuit. When they detect an open circuit from the pir this sets off an alarm!

 

What two devices are you triggering?

 

Can you use a relay to retrigger your devices?

 

what voltage do they use?

[kevmac72 0]

yes they both operate from a closed going open circuit. but i only have one pir to trigger both. It is triggering 2 digital video recorders. the whole system runs on 12v dc. I would rather not use a relay as it consumes power. the system i have is a low power sysem designed for prolonged deployments on batteries. any increase in load will reduce life span of batteries

[scorpion 0]

What happens when the PIR gives you an open. What do the two devices do? You said only one unit activates?

 

I was wondering if one multi channel 12 VDC recorder would consume less power than two recorders on the same battery?

 

Where are these recorders mounted? In a vehicles?

Is this a stealth system?

[scorpion 0]

I would make a circuit that would out put two low (0) signal.

This circuit could be powered only during an event. It would take the incoming lowsignal, latch it, and dual output circuits would latch low providing two low signals that are isolated, and it does not drain off of the battery.

 

The event trigger can reset the circuit as it is being energized.

 

74 series IC can accomodate your circuit. I wonder if CMOS ICs can be used for low drain. I do not know if you can make it static proof though.

 

What kind of battery are you using?

 

I assume you are using low current as you have not fried any reed relays.

 

What kind set up is this? Are the two DVRs located in a weatherproof housing?

 

_________________________________________________

 

Using a relay can be done by triggering it with a not circuit. The relay would only be energized at the time of the event.

_________________________________________________

 

What kind of DVRs are you using?

How long are they deployed?

 

Scorpion

[kevmac72 0]

i think i have cracked it. right or wrong it works. I have put both signal sides from the dvrs through diodes. i have commoned them then passed them through the switch (closed going open pir) i have then split this to both dvrs grounds. Bingo it triggers both simultaniously. I suppose the diodes stop the signals flying up the second devices signal output.

What do you think ? yes it is a bit of a sneaky peice of kit.

[scorpion 0]

I am glad the diodes worked well!

 

I am still curious to the setup that you are doing!

 

What kind of DVRs are you using?

 

(and the above posted questions)

 

Thanks!