Allen-Bradley MicroLogix 1400 - Chapter 7: Relay-Type (Bit) Instructions; XIC - Examine if Closed; XIO - Examine if Open

Publication 1766-RM001A-EN-P - October 2008
Using High-Speed Outputs 165
PWMX Operating Frequency Status (OFS)
The PWMX OFS (Output Frequency Status) is generated by the PWM
sub-system and can be used in the control program to monitor the actual
frequency produced by the PWM sub-system.
PWMX Duty Cycle (DC)
The PWMX DC (Duty Cycle) variable controls the output signal produced
by the PWM sub-system. Changing this variable in the control program
changes the output waveform. Typical values and output waveform:
• DC = 1000: 100% Output ON (constant, no waveform)
• DC = 750: 75% Output ON, 25% output OFF
• DC = 500: 50% Output ON, 50% output OFF
• DC = 250: 25% Output ON, 75% output OFF
• DC = 0: 0% Output OFF (constant, no waveform)
PWMX Duty Cycle Status (DCS)
The PWMX DCS (Duty Cycle Status) provides feedback from the PWM
sub-system. The Duty Cycle Status variable can be used within an input
instruction on a rung of logic to provide PWM system status to the
remaining control program.
Element Description Address Data Format Range Type User Program Access
OFS - PWM Operating Frequency Status PWMX:0.OFS long word
(32-bit INT)
0…40,000 status read only
Element Description Address Data Format Range Type User Program
Access
DC - PWM Duty Cycle PWMX:0.DC word (INT) 1…1000 control read/write
Element Description Address Data
Format
Range Type User Program
Access
DCS - PWM Duty Cycle Status PWMX:0.DC
S
word (INT) 1…1000 status read only
efesotomasyon.com - Allen Bradley,Rockwell,plc,servo,drive