Flip clock – one minute impulse 24vdc (+ and - in turns)

Projects General Guidance
1

I found a good looking Twemco flip clock. Unfortunately the unit is only a slave without control unit. The unit works with some type of two position “step motor”. If you supply the unit with +24vdc impulse, the minute changes. Then you need to supply -24vdc impulse to get the next minute. And then again +24vdc... I tested this manually with power supply and the clock works perfectly.

I read the instructions on http://arduino-info.wikispaces.com/ArduinoPower. Based on examples on that page I think my project can be solved with Arduino, relay and 24vdc power supply. Am I right? And an open issue is how to make the – and + change, do I need two relays (one supplying – every two minutes and other supplying + every two minutes?)

I would appreciate if somebody could guide me how to approach this project.
Thanks,
Miika

WP_20160116_005.jpg
WP_20160116_005.jpg1632×916 275 KB

2

You would need two relays or a motor control "H bridge" shield. I would prefer to use the motor controller but you should use whatever is easiest for you.

3

Using two relays, you need to wire one rela(A) to reverse the voltage when active. The other relay(B) then turns on the voltage.

First minute turn on B
Second minute turn on A then B then A off
Repeat.

Using a motor shield is easier as you simple reverse the drive each minute.

Weedpharma

4

IMO a pulse is sufficient, no need to apply the voltage all the time.
If you want to use a relay, take a DPDT one.

5

I meant pulse (forgot I was talking to non experienced member).

Weedpharma