you could do it with a 555 timer wired across the motor supply, so when the
motor has been running >2 seconds it times out and sounds the buzzer

Regards,

Kat.

> -----Original Message-----
> From: pic microcontroller discussion list
> [mailto:PICLIST@MITVMA.MIT.EDU]On Behalf Of Tal
> Sent: Monday, 2 June 2003 7:35 AM
> To: PICLIST@MITVMA.MIT.EDU
> Subject: [EE]: Need idea for elapsed time
>
>
> Hi All
>
> I need an idea for a circuit to check if a fixed time period (>2 sec) as
> passed.
> the circuit I am checking is a 12vdc pump if it working more than
> 2 sec then
> I need a high or low signal to start a buzzer..
> can you think about a cheap and easy solution?
>
> Regards
>
> Tal
>
> "I have not failed. I've just found 10,000 ways that won't work."
> Thomas Edison
>
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