RoboteQ AX3500 user manual Connecting Position Potentiometers to Analog Inputs

Connecting Sensors and Actuators to Input/Outputs

AX2500 Internal

Buffer and Resistor

+5V 14

10kOhm

Input

EStop/Inv 15

Ground 5

FIGURE 30. Emergency Stop / Invert switch wiring

The status of the EStop/Inv can be read at all times in the RS232 mode with the ?i com- mand string. The controller will respond with three sets of 2 digit numbers. The status of the ES/Inv Input is contained in the last set of numbers and may be 00 to indicate an Off state, or 01 to indicate an On state.

Analog Inputs

The controller has (2 on pre-RevB hardware) 4 Analog Inputs that can be used to connect position, speed, temperature, voltage or most other types of analog sensors. These inputs can be read at any time using the ?p query for Analog inputs 1 and 2 and the ?r query for Inputs 3 and 4. The following section show the various uses for these inputs.

Connecting Position Potentiometers to Analog Inputs

When configured in the Position mode, the controller’s analog inputs are used to obtain position information from a potentiometer coupled to the motor axle. This feature is useful in order to create very powerful servos as proposed in the figure below:

Position Feedback

Potentiometer

Gear box

FIGURE 31. Motor and potentiometer assembly for position servo operation

62 AX3500 Motor Controller User’s Manual Version 1.9b. June 1, 2007