- #1
belias
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Hello,
I'm looking for some help with a (hopefully) simple EE question regarding a DC circuit. I'm a chemical engineer and it's been a while since elec/mag physics for me :-) Here goes:
In my life outside engineering, I run a small ambulance service. Our ambulance has a rather annoying piezo buzzer that sounds any time the parking brake is in the "wrong" position (i.e. parking brake set and vehicle is in drive, or vice-versa). The problem is that it sounds every time the vehicle is shifted, since there's no delay (i.e. you'd have to simultaneously shift and adjust the parking brake to avoid the buzzer).
I'd like to add something to the circuit that adds about a 1 to 2 second delay before the buzzer sounds - however, the buzzer must turn OFF immediately when the voltage is removed. Ideally, I'm looking for something cheap and simple (as always)...
I seem to remember that inductors allow current flow in a time-dependent nature (i.e. ramp up from zero current) - am I on the right track?
Any help would be great!
P.S. The voltage is around 13.5 V DC, and I'd imagine the total current draw is < 200 mA. I have access to the buzzer (+13.5 and ground).
Thanks,
-Brian
I'm looking for some help with a (hopefully) simple EE question regarding a DC circuit. I'm a chemical engineer and it's been a while since elec/mag physics for me :-) Here goes:
In my life outside engineering, I run a small ambulance service. Our ambulance has a rather annoying piezo buzzer that sounds any time the parking brake is in the "wrong" position (i.e. parking brake set and vehicle is in drive, or vice-versa). The problem is that it sounds every time the vehicle is shifted, since there's no delay (i.e. you'd have to simultaneously shift and adjust the parking brake to avoid the buzzer).
I'd like to add something to the circuit that adds about a 1 to 2 second delay before the buzzer sounds - however, the buzzer must turn OFF immediately when the voltage is removed. Ideally, I'm looking for something cheap and simple (as always)...
I seem to remember that inductors allow current flow in a time-dependent nature (i.e. ramp up from zero current) - am I on the right track?
Any help would be great!
P.S. The voltage is around 13.5 V DC, and I'd imagine the total current draw is < 200 mA. I have access to the buzzer (+13.5 and ground).
Thanks,
-Brian