Dpdt reversing switch

Thread Starter


Joined Nov 25, 2009
I have a DPDT reversing switch circuit to change the direction that my motor turns. Power is sent to the motor via 555 timer circuit and then times out. The next time the timer is activated I would like for the motor to go in the opposite direction, so each time the motor turns on it will alternate between the forward and reverse. This may be something thats just not clicking in my pea size brain, but if you have any information it would greatly be appreciated. Schematics are a big help for me to understand easier :)

Thank you in advance for you time.

Potato Pudding

Joined Jun 11, 2010
You need to provide more detail.

Do you want the intervals to be forward then off, and then reverse on next trigger and then off?

It is unclear if you want a triggered on pulse with automatic reversal for alternate pulses or you want the motor to continuously spin back and forth.

Is your 555 a monostable or astable circuit?


Joined May 20, 2006
Do you want the motor to run one way for eg 10 secs, reverse for eg 10 secs, then stop ?

Does it matter that a timer may give you slightly different number of turns each way / each time ?

Does it matter if motor is thrown into full reverse while turning forwards ?

( I ran into this problem building light-sensing mini-robots: The motor control needed a brief 'off' time to prevent excess current flow at switch-over... )

Does the system need micro-switch end-stops ? eg a model train or actuator system that shunts from end to end periodically ??