joan wrote:Measure the voltage.
iinnovations wrote:Good luck measuring the transient voltage without a time-resolved, scope-like tool. I'd be interested to see that curve if you do measure it ... I would guess that it's a single discharge independent of any momentary switching closure length, but who knows. Just a cap methinks.
DougieLawson wrote:Best of luck trying to spot an event that lasts 1/60th of a second with a meter.
I've read this thread several times, but still haven't worked out what people mean ...
Before the switch closure there are some volts across the switch.
I'd have thought it wasn't many, as sticking a high voltage on contacts that can be touched could be a bad idea, but who knows?
Whatever, that voltage just sits there, so measuring it with a meter is straight forward, isn't it? No nasty short-term pulses or the like?
So measure the voltage, and you know what your switch has to withstand, be-it a relay, opto-coupler, transistor, whatever ...
When the switch closes, there's no voltage to measure. It's zero.
Maybe current in a short pulse, and a meter is going to be useless for measuring that. But then your very expensive 500MHz Tektronix 'scope is also going to useless without an expensive current probe
But surely, the designer of the gun isn't going to rely on someone else's weedy switch to carry anything high-speed or high-current - there'll be some electronics as an interface. So all you need to do is interface with that.
Even a BC108 should work.
Not that a Xenon flash is any use for the Pi's camera, but for anything else ...