Thermocouple and RTD are contactless temperature measurement of temperature measurement, although its the same, it is measuring the temperature of a body, but their principles and characteristics are different.First of all, introduce the thermocouple. The temperature of thermocouple temperature measurement is the most widely used devices, whose main features are wide temperature range, stable performance, … Continue reading Difference of thermocouple and thermal resistance

Hardware differencesS7-300 in order to meet the large and middle scale control system, and design more modular. S7-200 series is integral, CPU module, the I/O module and the power supply module in a module, called CPU modules and S7-300 series, from the power supply, I/O,CPU and the rail is a separate module.Actually S7-200 series can … Continue reading Difference between Simens PLC S7-200 and S7-300

1, MPI is a Multi-Point Interface, suitable for PLC 200/300/400, operator Panel PC MPI/PROFIBUS and TP/OP communication card, supported MPI network communication speed for the network communication speed of 12Mbit/s. MPI network can connect up with 32 nodes, maximum communication distance is 50m, but can use repeaters to extend the length.PPI Protocol is a communications … Continue reading ppi_mpi_profibus

If understood as PLC ladder diagram circuit, judging from the perspective of the relationship between the input and output are both combinational and sequential circuits, if according to the input of the deterministic case, circuit and random circuits have two.(1) combination circuitOutput only with the input of the current situation, regardless of the input history … Continue reading Circuit type of PLC parsing programming

OMRON PLC can not communicate with TP177B / DP touch screen,  But TP177A / DP and other communication with the screen (have repeatedly tested)Specific settings Communication Notes:(1) All communication settings (HMI and PLC) must be consistent (station number, baud rate, parity, etc.,   Use the default values ​​here namely: "9600,7, Even / even, 2");(2) CPU-42H 4 feet should … Continue reading Omron PLC and Siemens touch screen Communication setting method

A, normally-off mark What does this mean? Under what circumstances can use normally-off signs, normally-off flag at what time it is turned on?(Normally open) Under what circumstances will the conductor, generally not allowed to handle the case 1.P_OFF ​​bit set to ONFor example, CNT command, if a customer is not allowed in any case reset, … Continue reading Omron PLC technical problems and solutions

Format: LAR1Note: the load address of the operand register 1 (ARl);Format: LAR2Note: the load address of the operand register 2 (AR2);Format: TAR1Description: pass the contents of the ARl to store or AR2;Format: TAR2Description: pass the contents of the ARl to store or AR2;Format: CARDescription: swaps the contents of ARl and AR2   LARl P#I0.0                         //input I0.0 … Continue reading Siemens S7 PLC address register load and transmission

Characters in the remaining time of the timer value is saved in the binary format, l instruction read binary in the timers time value into accumulator 1, known as direct mount. LC instructions to DCD format can also be used to read out time value, loaded in accumulator 1 low, called BCD code formats read … Continue reading PLC Siemens S7 series into time or count values