Example 8: Blinking Circuit; Example 9: Triggered Circuit - Delta C2000 series User Manual

The figure above is a very simple ladder step diagram. When starting to scan Y1 normally close
contact, Y1 normally close contact is close due to the coil Y1 is OFF. Then it will scan Y1 and the
coil Y1 will be ON and output 1. In the next scan period to scan normally close contact Y1, Y1
normally close contact will be open due to Y1 is ON. Finally, coil Y1 will be OFF. The result of
repeated scan, coil Y will output the vibrating pulse with cycle time ΔT (On) +ΔT (Off).
The vibrating circuitry of cycle time ΔT (On) +ΔT (Off):
X0 Y1
T0
The figure above uses timer T0 to control coil Y1 to be ON. After Y1 is ON, timer T0 will be
closed at the next scan period and output Y1. The oscillating circuit will be shown as above. (n is
the setting of timer and it is decimal number. T is the base of timer. (clock period))

Example 8: Blinking Circuit

X0 T2
TMR
T1
TMR
X0 T1
Y1
The figure above is common used oscillating circuit for indication light blinks or buzzer alarms. It
uses two timers to control On/OFF time of Y1 coil. If figure, n1 and n2 are timer setting of T1 and T2.
T is the base of timer (clock period)

Example 9: Triggered Circuit

X0
M0
Y1
M0 Y1
In figure above, the rising-edge differential command of X0 will make coil M0 to have a single
pulse of ΔT (a scan time). Y1 will be ON during this scan time. In the next scan time, coil M0 will be
OFF, normally close M0 and normally close Y1 are all closed. However, coil Y1 will keep on being
ON and it will make coil Y1 to be OFF once a rising-edge comes after input X0 and coil M0 is ON
for a scan time. The timing chart is as shown above. This circuit usually executes alternate two
actions with an input. From above timing: when input X0 is a square wave of a period T, output coil
Y1 is square wave of a period 2T.
TMR T0 Kn
Y1
T1 Kn1
T2 Kn2
M0
Y1
16-17
Chapter 16 PLC Function C2000 Series
X0
Y1
n T
X0
Y1
n1
X0
T
M0
Y1
T
n2 T
*
T
*