The programmable logic controller, better known as the PLC is known, plays a role in almost all automated production processes. The SPS is a programmable electronic device that is used almost infinite number of combinations of relays, contacts and timing circuits to control industrial machinery of all types and sizes. It is basically a computer designed to withstand a harsh environment production. It 'was designed to replace a complex system of relays, cam switches, and otherelectromechanical circuits. The first PLC was introduced in late 1970, continue to exist and grow in popularity since its publication.
PLCs are produced today by many major manufacturers including Siemens, Allen Bradley, Koyo, Fuji, Mitsubishi and Telemecanique, and a host of others. The PLC programming is done via proprietary software produced by the manufacturer. The software is not compatible with PLC and logic programmingalthough it is very similar, has many subtle differences between different brands. The program is stored in the PLC ladder logic program is called. Problems in the ladder program can be very involved, and this is another subject altogether. Hardware problems are very similar and can be easily diagnosed, if a little 'the specific model and know it's input and output configuration.
Programmable Logic Controller
Hardware failure of the brain, or main processor, is rare. You canusually easily diagnosed visually by an illuminated display error on the face of the PLC. A blackout would have a chance to display inside the PLC, or Power-screen does not light have been checked and the technician that the correct voltage is applied to the terminals. Some controllers have an internal fuse that can do without furniture. These problems are not common as a failure of an input or output.
Inputs and outputs are available in variousConfigurations and voltages. Both AC and DC are available separately and sometimes in the same unit. These inputs / outputs and analog inputs, and can be configured as an output transistor or relay dry contact. Both the input and output side, it is important to determine the specifications of the PC before. After the appropriate software PLC, which is also necessary, when solving problems.
The first recommendation would be to compare the inputs and illuminatedLeave the real-time software. An entry is not displayed properly illuminated under stress as input into the software indicates a failed or the door open. On the output side, a terminal is not turned on, the correct implementation of the output voltage to mean two things, the issue has failed in an open position, or the wrong voltage is applied to the common output terminal. The only way to verify this could be adjusted using a multimeter on the rightVoltage scale.
Overall, PLC hardware troubleshooting is not complex, but must be addressed in an orderly fashion, as both hardware and software are required to work in harmony for a PLC to perform the tasks.
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