Publication 1763-RM001C-EN-P - October 2009
156
Using High-Speed Outputs
PWM Enable Status (ES)
The PWM ES (Enable Status) is controlled by the PWM sub-system. When
the rung preceding the PWM instruction is solved true, the PWM
instruction is enabled, and the enable status bit is set. When the rung
preceding the PWM instruction transitions to a false state, the enable
status bit is reset (0) immediately.
•
Set (1) - PWM is enabled.
•
Cleared (0) - PWM has completed or the rung preceding the PWM is
false.
PWM Output Frequency (OF)
The PWM OF (Output Frequency) variable defines the frequency of the
PWM function. This frequency can be changed at any time. In the
MicroLogix 1100 Series A controller, the data less than zero or greater than
20,000 generates a PWM error. However, in the MicroLogix 1100 Series B
controller, the data less than zero or greater than 40,000 generates a PWM
error.
Element Description
Address
Data Format
Range Type
User Program
Access
ES - PWM Enable Status
PWM:0/ES bit
0 or 1
status
read only
Element Description
Address
Data Format
Range
Type
User Program Access
Controller
Series
OF - PWM Output Frequency
PWM:0.OF
word (INT)
0 to 20,000
control read/write
A
word (UINT)
0 to 40,000
B
ATTENTION
In order to use 40kHz PTO and PWM with a prior version
of RSLogix 500 (version 7.10 or lower), variable type
change process is required (unsigned integer to signed
integer). Refer to PTO and PWM function file changes in
Series B Controller on page 569 in
40kHz PTO/PWM of MicroLogix 1100 Series B Controller
for more information.
efesotomasyon.com - Allen Bradley,Rockwell,plc,servo,drive