ESCON: Using an external potentiometer for set value commanding

Topic:

• How to connect an external potentiometer to the ESCON for command the set value?
• How has the ESCON to be configured to command the set value by an external potentiometer?

Solution:

The ESCON servo controller can be controlled by an analog or PWM set value. The analog set value can be provided by as an analog voltage (e.g. analog output of a PLC for example) or an external or internal potentiometer.

Wiring of an external potentiometer used as set value:

An external potentiometer has to be connected to the ESCON's analog input like shown in the following drawing:

Important:

• It is recommended to us a 10 kOhm potentiometer.
• A potentiometer with less than 4.7 kOhm should not be in use due to the fact that the 5V output voltage might be overloaded then in case of other peripherals (e.g. encoder, hall sensors, I/Os) which are also supplied by the internally same 5V.

Remarks:

• The voltage applied to the analog input of the ESCON can be adjusted in between 0 ... 5V by the external potentiometer's supply shown by the drawing above.
• The voltage range of 0 ... 5V has to be mapped to the required motor current range (in case of current control) resp. motor speed range (in case of velocity control).

ESCON set value configuration:

ESCON Studio's Startup wizard has to be used to configure the set value interface. The dialog window "Set Value" lets you do that.

• Set value type:
  Independent if the set value is applied as an analog voltage directly or by the means of an external potentiometer there has to be the "Set Value" type "Analog Set Value" selected.
• Scaling of the set value range:
  The voltage range of the set value signal has to be mapped to the corresponding motor current range (in case of current control) resp. speed range (in case of velocity control).

Please find three examples of possible configurations in case of a unidirectional or bidirectional speed range commanding by the external potentiometer.

Example 1: Unidirectional speed range commanding

Requirement:
The motor speed should be adjusted by the external potentiometer within the range of
0 up to 8000 rpm

Configuration:

Example 2: Bidirectional speed range commanding

Requirement:
The motor speed should be adjusted by the external potentiometer within the range of
-8000 up to 8000 rpm

Configuration:

Example 3: Selecting the direction by a digital input

Requirement:
The motor speed should be adjusted by the external potentiometer within the range of
0  up to 8000 rpm
and the rotation of direction should be selected by a digital input.

Configuration: