Rockwell Automation GMLC Reference Manual - Manual (Page 535)

Publication GMLC-5.2 - November 1999
498 Controller Variables
Analog Inputs
Four analog inputs are available as an option on IMC-S/20x-A and IMC-
21x-A model motion controllers for reading the values from analog
transducers, etc. Analog input values range between ±10 volts, depending
on the input level.
In the Tag Explorer, select General System Variables, then select
Analog_Input_0-3 in the Tag Window.
If you selected i CODE version 2.4, or earlier, in the Configure Control
Options dialog box, the motion controller can read voltage on each analog
input at any time by using the appropriate analog input variable. IMC S
Class Compact (IMC-S/23x) motion controllers use Flex I/O to provide
analog inputs.
If you selected i CODE version 3.0, or later, in the Configure Control
Options dialog box, you must select Flex I/O in the Tag Explorer to select
defined analog inputs in the Tag Window. See Inputs and Outputs for
more information.
See the Online Help for more information on configuring and defining
Flex I/O analog inputs.
Free Running Clock
The free running clock is a count-up timer that runs continuously
whenever the motion controller is powered. Its values are displayed as
seconds. You can use the Set Timer block to set the free running clock to a
value, and you can read the free running clock’s value using the
Free_Running_Clock variable.
In the Tag Explorer, select General System Variables, then select
Free_Running_Clock in the Tag Window.
Use the free running clock for timing the length of events. Se
Free_Running_Clock is a double precision floating point value with a
practical maximum limit of 15 significant digits.