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 … Continue reading FCS, DCS, PLC control system Characteristics and differences
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 only has … Continue reading Fieldbus DCS, and FCS
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 blive … Continue reading S7-300/400 plc the difference between FC and FB
S7-300 PLC arbitrary bit (greater than 32) rotate left
Greater than 32 bits Arbitrary bit Rotate Left an idea. In 64 + N bits, for example,First, each Rotate Left Double Word 1, respectively,Double the maximum displacement of each word to its lowest position. Then each of the least significant bit double word is transmitted to the double word to its left is the least significant … Continue reading S7-300 PLC arbitrary bit (greater than 32) rotate left
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 … Continue reading S7-200PLC the PPI protocol
How to choose PNP or NPN
10 ~ 30VDC proximity switch connected with PLC, how to choose a PNP or NPN1, 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 of … Continue reading How to choose PNP or NPN
PLC alarm circuit Ladder Logic
That is the condition for the alarm input X0 X0 = ON alarm requirements.Alarm lamp output Y0, Y1 alarm buzzer.Y0 flashing alarm when its oscillation cycle 1s;Y1 tweet.X1 alarm response, alarm X1 after blinking and stays ON Y0, Y1 tweet closed.X2 is alarm lamp test signal, i.e., Y0 X2 turns ON.①Y0 need an oscillator signal.② … Continue reading PLC alarm circuit Ladder Logic
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 … Continue reading PLC oscillation circuit Ladder Logic
PLC off delay circuit Ladder Logic
Enter Ⅹ0 termination without delay self-locking button opens the circuit Ladder Logic.When the input terminal is turned Ⅹ0, R0 internal relay coil is turned on, its normally open contact closure output Y0 R0 is turned on, and the timer T0 start time, the delay 5s, T0 normally closed contacts open, the output Y0 is OFF … Continue reading PLC off delay circuit Ladder Logic
PLC ON delay circuit Ladder Logic
Input Ⅹ0, X1 is not connected with self-locking button controlled device connected to the output terminal Y0. When the input signal is turned Ⅹ0 terminal, enter the relay coil Ⅹ0 turned on, its normally open contact Ⅹ0 closed, internal relay R0 is turned on, its normally open contact closure R0, ON timer T0, T0 is set … Continue reading PLC ON delay circuit Ladder Logic
PLC ONE 