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By lukas1901
#198996
Greetings,

My project is to fire the shutter of 8 disposable cameras at the same moment in order to capture an action from several different perspectives at the same moment (think "bullet time" in The Matrix).

Now I am very new to Arduinos/Electronics, however I have gotten myself through an Arduino 2560 Starter kit and the best solution I've found in my mind is to trigger the solenoids via a 5v relay so I don't blow up my arduino.

I've found an 8-channel SRD-05VDC-SL-C relay.

The solenoids I am looking at are:
Solenoid repelling 0.18 N/mm 2 N/mm 12 Vdc 1.1 W
https://www.conrad.com/ce/en/product/50 ... archDetail

These will then be mounted on top of the disposable camera to push the plastic button. You can see it here:
https://www.bhphotovideo.com/images/ima ... 906263.jpg

So the required amperage is watts divided by volts right? So I will need a 12vdc power source with 100mA or will I need to have 800mA capability (8 solenoids at 100mA at same time)? What kind of device could I plug into the wall to connect to the relay to power this? Or what kind of device could I use to power it without a wall outlet?

Thanks for the help (apologies for stupid questions).
Cheers!
User avatar
By DanV
#199002
You will experience a delay while the relays actuate.
Typical pull-in times for mechanical relays are 8 - 15 milliseconds.
Then you will experience a similar delay with the solenoids.
If that doesn't affect you, the solenoid inrush current will - it can easily be 10 times the holding current.
Why not just get a 10 amp power supply.

Or hack the camera to actuate the electronics in the camera - exactly as the switch on the camera does.
Then you can just use a transistor to fire the cameras.