Quadrature encoder cables
Wildatheart
Posts: 195
I have a design that uses 2 Vishay TCST-2103 optical slot switches in conjunction with a slotted wheel to make a quadrature encoder. I would like to use two standard BRW (3 wire) servo cables to connect the slot switches to a Propeller mini board. Each cable transmits power and signal over a distance of about 3 inches, and the cables are in direct contact with the side case of a Parallax continuous rotation servo.
Typically, encoder cables are shielded. I am expecting a maximum pulse rate of about 200 pulses per second. The question is am I asking for trouble by using unshielded cables in immediate contact with the continuous rotation servo?
A second question is Experimentation shows that the voltage swings from near zero to 2.93 volts is it reasonable to feed the signals directly into the Propeller mini without the aid of a Schmidt trigger?
Thanks for the suggestions.
http://www.vishay.com/docs/81147/tcst2103.pdf
Typically, encoder cables are shielded. I am expecting a maximum pulse rate of about 200 pulses per second. The question is am I asking for trouble by using unshielded cables in immediate contact with the continuous rotation servo?
A second question is Experimentation shows that the voltage swings from near zero to 2.93 volts is it reasonable to feed the signals directly into the Propeller mini without the aid of a Schmidt trigger?
Thanks for the suggestions.
http://www.vishay.com/docs/81147/tcst2103.pdf
Comments
be careful not to run them alongside the power wiring to the servo. After all servos themselves
handle worse as the signal runs alonside motor power.
In general high speed logic runs upto 6 to 10 inches are OK if there is a good ground return
path.