User Manual

Connecting Sensors and Actuators to Input/Outputs
58 Advanced Digital Motor Controller User Manual V2.0, July 8, 2019
Example: a motor spinning at 10,000 RPM max, with an encoder with 200 Pulses per Rev-
olution would generate:
10,000 / 60 * 200 * 4 = 133.3 kHz which is well within the 1MHz maximum supported by
the encoder input.
An encoder with 200 Pulses per Revolutions is a good choice for most applications.
A higher resolution will cause the counter to count faster than necessary and possibly
reach the controller’s maximum frequency limit.
An encoder with a much lower resolution will cause speed to be measured with less precision.
Connecting the Encoder
Encoders connect directly to pins present on the controller’s connector. The connector
provides 5V power to the encoders and has inputs for the two quadrature signals from
each encoder. The figure below shows the connection to the encoder.
Encoder
Controller
GND
5V Out
ENC1A (ENC2A)
Ch A
Ch B
ENC1B (ENC2B)
5V
GND
FIGURE 3-19. Controller connection to typical Encoder
For several controller models, the Encoder inputs are by default mapped in Molex connec-
tor. In order to be able to use encoders and SSI sensors at the same time (see “MLX” in
the command reference section), the encoders can be mapped to DB25 connector pins
where pulse inputs are.
Cable Length and Noise Considerations
The cable should not exceed one 3’ (one meter) to avoid electrical noise to be captured
by the wiring. A ferrite core filter should be inserted near the controller for length beyond
2’ (60 cm). For longer cable length use an oscilloscope to verify signal integrity on each of
the pulse channels and on the power supply.