That latch idea is neat! Both should work a treat.
Anders
On Wed, Dec 7, 2022, 9:44 AM Patrick Finnegan via cctalk <
cctalk(a)classiccmp.org> wrote:
On Wed, Dec 7, 2022 at 12:40 AM Jim Brain via cctalk
<
cctalk(a)classiccmp.org>
wrote:
This might be a bit off topic, so forgive me if
so.
The issue is a 24VAC motor with one connection to 24VAC and the other
gated via two switches. The first switch is a momentary one and the
second is in parallel and connected to the motor. A long enough
momentary depression on the first switch actuates the electric motor
enough to close the second switch, which then stays closed for 1
revolution.
The problem is that a quick enough press and release of the first switch
does not allow the motor to move far enough to close the second switch.
Given the configuration, my general plan was a small one shot timer
circuit that energized when the switch was initially depressed and then
closed a relay in parallel with the first 2 switches, with a time period
that was 1/10 to 1/2 the time of the motor revolution. a quick close and
release of the first switch would start the timer, which would then
close the parallel switch and then open it a short time later, and then
the motor switch, which would still be closed, could signal the end of
the cycle.
My two thoughts would be:
1) A 555-timer in one-shot mode
2) An S-R latch at is set by the push button, and cleared by 2nd switch
Pat