Equipments (Devices) > PLC200 > Program > Hardware

Block that inserts a PWM signal into the selected digital output.

Ladder Representation

PWM_G0

Block Structure

Variable Type	Name	Data Type	Description
VAR_INPUT	EN	BOOL	Block enabling
	Frequency	DWORD UDINT	PWM frequency
	Width	WORD	Pulse width
	OutputNumber	CONST BYTE	Output for the signal to be generated
VAR_OUTPUT	Q	BOOL	Output enabling
VAR	PWM_INST_0	PWM	Instance of access to block structure

Operation

This block, when it has a TRUE value in EN, inserts into the selected output a PWM signal with a frequency determined in Frequency (between 0 and 300 kHz) and pulse width determined by Width (between 0 and 1000, where 1000 would be 100% cycle active).

NOTE!

This block has priority over any coil that is writing data to the selected output.

The ENO value forwards to the next Ladder block the EN value after the operation is completed.

Block Flowchart

PWM_flowchart

Example in Ladder

PWMv2_example01

The above example enables a PWM signal in DO1 with a frequency of 500 Hz and a duty cycle of 20%. The block ends with success; Q output is activated.

Example in ST

The example below displays instructions for applying the example above in ST language.

VAR

FREQUENCY : UDINT := 500;

WIDTH : UINT := 200;

start : BOOL := 0 ;

coil : BOOL;

PWM_INST_0 : FB_PWM;

END_VAR

PWM_INST_0.EN := start;

PWM_INST_0(Frequency:=FREQUENCY, Width:=WIDTH, OutputNumber:=1);

coil := PWM_INST_0.Q;