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Delta Electronics AC Motor Drive VFD-E User Manual

Page 298

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Appendix D How to Use PLC Function|

Revision June 2008, 04EE, SW--PW V1.11/CTL V2.11

D-15

Example 3: the latching circuit of SET and RST commands

SET

Y1

RST

Y1

X1

X2

Top priority of stop

The figure at the right side is latching circuit that made

up of RST and SET command.

It is top priority of stop when RST command is set

behind SET command. When executing PLC from up

to down, The coil Y1 is ON and coil Y1 will be OFF

when X1 and X2 act at the same time, therefore it calls

priority of stop.

It is top priority of start when SET command is set after

RST command. When X1 and X2 act at the same

time, Y1 is ON so it calls top priority of start.

SET

Y1

RST

Y1

X2

X1

Top priority of start

„

The common control circuit

Example 4: condition control

X3

Y1

X1

Y1

X4

Y2

X2

Y2

Y1

X1

X3

X2

X4

Y1

Y2

X1 and X3 can start/stop Y1 separately, X2 and X4 can start/stop Y2 separately and they are all

self latched circuit. Y1 is an element for Y2 to do AND function due to the normally open contact

connects to Y2 in series. Therefore, Y1 is the input of Y2 and Y2 is also the input of Y1.