Siemens S7-200 User Manual download pdf (Page 66)

Bridge Circuit

If you are changing over from contactor technology to PLC technology will very probably encounter

switch combinations that cannot be converted directly into ladder diagram representation. Included

among these is the bridge circuit. Brief solutions are sketched here both for the simple and the more

complex bridge circuit.

1) Simple bridge circuit

2) Complex bridge circuit

Appendix

Tips

You will find a few valuable

tips on these pages.

The two possible current paths have been converted again and recombined. On

the one hand, a,c parallel b, on the other b,c parallel a. For ease of comparison,

we have arranged the ladder diagram vertically.

In new projects, avoid using the bridge circuit in the circuit diagram where pos-

sible! Think "in ladder diagram" right from the start.

The simple bridge circuit (left) is implemented with two networks. The individual

possible current paths are simply split up. For ease of comparison, we have

likewise arranged the ladder diagram vertically.

ab c

Latching Revision

Pulse-Oper-

ated Switch

Off-Delay

Timer

Sequencer Appendix

1 2 ... 61 62 63 64 65 66 67 68 69 70 71 72 73 74

No comments

Siemens S7-200 User Manual Page 66