FCS, DCS, PLC control system Characteristics and differences

90 ‘s of the last century to the practicality of the fieldbus control system is a rapid momentum of rapid development, is currently the world‘s most modern control systems. Fieldbus control system is a focus in automation technology, is growing by domestic and foreign manufacturers of automation equipment and user attention. The appearance of fieldbus […]

Fieldbus DCS, and FCS

FCS is the spot bus control technology, which is the same thing. FCS was developed by PLC of, while in other industries, developed by DCS and FCS come from, so between PLC and DCS and FCS are inextricably linked, and there is a profound difference. FCS was developed from DCS and PLC, and FCS not […]

S7-300/400 plc the difference between FC and FB

1. FB har en baggrund luns, FC har ikke en baggrund luns. Dette er den mest afgørende forskel. Baggrund datablokke styres hver af en privat butik, som om kontrolleret personlig værdiboks i banken. Temp er mere end FB, FC blev opkrævet med en fælles dataområde, ligesom opslagstavler, alle kan underskrive en bekendtgørelse, sendt meddelelser vil […]

S7-200PLC the PPI protocol

Hardware and software methods by listening, analyzing internal PLC inherent PPI protocol, then the host computer using VB programming, follow the PPI protocol, data reading and writing PLC, man-machine operation tasks. This communication method, compared with the general freedom of communication protocols, omitted through the PLC programming, just the preparation of the PC communication program […]

How to choose PNP or NPN

10 ~ 30VDC proximity switch connected with PLC, how to choose a PNP or NPN 1, drain input, the input terminal originally designed for short to ground on the trigger to open into effective! It does not constitute a hazard to the power supply system, due to power failure will not affect the normal operation […]

PLC oscillation circuit Ladder Logic

Oscillation circuit analysisX0 turns T1 coil excited,4s after T1 delay normally open contact closure,While T2, Y1 coil excited, Y1 output.After T2 coil excited 2s produce a series of actions in the following order (note the timing chart corresponding analysis). ①T2 normally closed contacts disconnect② make T1 energized coil,③ T1 coil power loss and enable T1 normally […]