To reduce the cost of using the system, it can be considered from two perspectives, hardware and software, in terms of

hardware can be considered through the combination of circuitry to reduce the opportunity to use I/O points, in terms

of software is to expand the use of I/O points through the combination of the program value, to achieve a little multi-use.

A: the hardware to achieve cost reduction

Hardware to reduce costs in the use of existing PLC design control system has practical significance. Several methods can

be used to achieve the following:　

(1) external signal grouping input:

In the system with manual control and automatic control of two effects, automatic control procedures and manual control

procedures are generally not implemented at the same time. At this time, the automatic and manual signals can be

grouped according to the different control states required to access the PLC input terminals

SBI and SB2 buttons are used X0 input, but they are not simultaneously play a role, so that through the conversion of the

PLC hardware common point (COM) wiring and software time-sharing implementation of their different methods of user

programs, so that the PLC of an input point can be respectively respond to the state of the two input signals. The role of

two input points to complete the PLC in two working states of the input function, to improve the efficiency of the use of

PLC input points, saving the actual number of PLC input points. The SA is used to select the automatic/manual program for

automatic/manual switching and he diode is used to cut off the parasitic signal to avoid the generation of false signals.

(2) Combined input switching components

In the motor control circuit shown in Figure 2(a) for multi-point start/stop, the motor can be controlled to start and stop at

different places. If PLC control is used, the wiring methods in Fig. 2(b) and (c) can be used respectively. 

The below PLC parts will you need?  Contact with Vivi (sh_plc@163.com). 

B&R X20CS1030 Communication Module

Siemens 6ES7590-1AE80-0AA0 Mounting Rail

B&R X20AO2632 ANALOG OUTPUT MODULE

Allen Bradley 1763-L16DWD Micrologix 1100 Programmable Controller