How can you troubleshoot PLC programs without causing equipment damage?

Start by checking the input devices, such as sensors and switches. Ensure they are correctly wired and functioning as expected. Testing these devices with a multimeter can help identify faulty input components

Identify the kind of PLC and its I/O which needs to be dealt with. Understand its functionality and the issues causing the requirements for a troubleshooting.

The best way to solve this problem is by simulating the PLC program using simulation software. This allows you to identify any issues before uploading the program to the actual PLC.

INGENIERIA INVERSA........ CON EL MANUAL O EL OPERARIO ENCARGADO DE ESA MAQUINA SE DEBE COTEJAR LAS FUNCIONES Y LOS TIEMPOS DE CADA PROCESO PARA TENER UN IDEA DE LAS FUNCIONES DE LA MISMA. UNA VEZ TENIENDO EN CUENTA LOS DATOS SE CREA UNA EXTRUTURA EN BORRARDOR DE ESAS SECUENCIAS Y DE HAY SE COTEJA CON LA QUE TIENE GRABADA EL PLC. EN EL CASO DE QUE FALLE EL SOFTWARE. EN EL CASO DE QUE NO SOLO SE DEBE IDENTIFICAR LA FUNCIONES QUE NO ACTUAEN POR ENDE DESCARTAS SI TENES FALLAS EN SENSORES O ACTUADORES. PARA NO SER TAN EXTENSO EN BUSCAR CAUSAS EN SUPUESTAS HIPOTESIS LO MEJOR ES HACER LO SIGUIEN . APRENDER LAS FUNCIONES DE LAS MAQUINAS PARA PODER DESCARTAR DISTINTOS TIPOS DE FALLAS EN UN BREVE TIEMPO.

Simulation/ emulation software is available to test the code without activating the outputs. Allen Bradley PLC also have a "test mode" that can be used to troubleshoot with no interaction with the output.

Whats the Risk of not meeting the Requirement requires that you Define a User Requirement. One of My favorite User Requirements is it doesn't kill, life impair, or require serious outside aid. Upon determining the Risk of the problems you may add Corrective Action Plans which are similar to Large Action Plans. Based on X Criteria within a State Machine, this is the Prescribed Action Plan. Its expected for Instruments to Lie or provide faulty data when they fail. If it is important that the accuracy of the instrument is required additional plans like Validation Schedule, or Calibration if Custom Requires. Ultimately the Failure Mode Effect analysis is the most important document

LOS PROBLEMAS PUENDEN SER 3 ENTRADAS, SALIDAS, SOFTWARE SE IDENTIFICA LA FUNCION QUE NO CUMPLE PARA AISLAR EL PROBLEMA Y LISTO

Check whether the issue is causing an external problems on the logic or is it the system is malfunctioning. Many a times it might be a simple case of battery exhaust, PLC overload of memory.

Problem can be identify by various methods. Logical errors Current/voltage fluctuations Input and Output systems Sensor feedback issue Electromechanical issues like failure of gear, drive, Heating issues, Wire resistance failure. Overdrive of servos, High fatigue loadings

Lo más difícil de encontrar son las fallas esporádicas cuando no hay un buen sistema de registro de eventos históricos, en caso de tener registro de eventos se puede ver al milisegundo la secuencia de eventos que llevan a la falla actual, en algunos sistemas al hacer "acknowledge" del defecto éste sale del histórico y después no podemos explicar la falla ni hacer correctamente el reporte, hay que tener un poco de paciencia y documentar, una foto en el momento adecuado de la pantalla evita muchas explicaciones y sospechas

Check the program offline using simulation technique to replicate the issue. Fix the problem and run it multiple times by simulating different field conditions. Eliminate all possible issues and ensure that the program is right. Then at the right opportunity download the program to PLC. If situation can wait download during shutdown and take a trial.

LO IDEAL SERIA HACER UN DAMP EN UNA PC Y EMULARLO CON RESPECTO AL HARDWARE PODE USAR CUALQUIER HERRAMIENTA PERO SI QUERES PRESICION USAS UN OSILOSCOPIO PARA VER LA FRECUENCIA DE TRABAJO.

Best way is to reassign those IOs to a different location. If the problem is pertaining to a sub routine then isolate the sub routine only in the logic. This can be tested out in simulation mode and redone.

To troubleshoot PLC programs safely: 1. Understand the program and back it up. 2. Use simulation mode to test without affecting equipment. 3. Inspect input/output devices and wiring. 4. Monitor PLC status for anomalies. 5. Isolate and test program sections individually. 6. Document and communicate changes. 7. Test in a controlled environment. 8. Follow safety procedures and use appropriate PPE.

Once you identify the issue and isolate it. If you have signal conversion issue from analog to digital or vice versa , Check the COMM Port, there maybe port issue, loose connection, dust collection, Or if whole MOXA device is giving flickers or variations , Make an SOP and replace it

Simulation of the altered logic. Reintroduction of a sub routine after modifications. Many times it might be a case of memory overwrite on the same data. This can be solved by reassigning the registries.

SIEMPRE SE HACEN NOTACIONES DE CADA INSTRUCCION PARA TENER EL PASO A PASO DETALLADO Y NO COMETER ERRORES. NO SE SI EDITAR EL SOFT SERIA LO IDEAL. CADA FABRICANTE LE BRINDO FUNCIONES ESPECIFICAS DE TRABAJO PARA QUE EL PRODUCTO A TERMINAR SE EL DESEADO. LO QUE SI PODRIA HACER ES UNA RESTAURACION DE FABRICA DE ESE SOFT.

Antes de pasar ningún cambio asegurarse de hacer un backup de lo actual y de ser capaz de volver a la situación actual, en muchas ocasiones se modifica el software para después detectar un sensor en mal estado o un problema electromecánico y hay que ser capaz de volver a cero, incluso está el riesgo de errar en el cambio del programa y la salida más rápida es restaurar el programa al estado anterior

Under the Failure Mode Effect Analysis (FMEA) there is a Category of Device Failure Mode Effect Analysis. If the Severity of the Failure is worse than replace the part and could harm people, environment, assets or reputation this severity may lead to additional user requirements added to corrective action plans, warnings of pre-mature failure linked to like alarm rationalization, interlocks or safety devices to assure safe state shutdown, and preventative maintenance plans which belong to the failure mode effect analysis of the Assets. The Device Failure Mode Effect Analysis often can be used to Generate the Installation Qualification of Assets.

SIEMPRE SE DEBE EMULAR POR UNA CUESTION DE SEGURIDAD E INTEGRIDAD TANTO DE LA MAQUINARIA COMO DEL OPERARIO. APARTE DESCONECTANDO DE LA RED TAMBIEN PODES VERIFICAR SI LA ESTATICA O TIERRA DE LA MAQUINA ESTA DESCARGANDO BIEN. LA FALTA DE MATENIMIENTO PROBOCA EL MAL FUNCIONAMIENTO DE LOS PLC.

UNA VEZ UN MOTOR EN SU PARADA TIRABA UN FLYBACK A TIERRA Y PROBOCABA QUE EL PLC SE DESPROGRAMARA. TENIA LOS CABLES DE TIERRA CON HONGOS Y RESECOS

To troubleshoot PLC programs without causing equipment damage, backup the program, use simulation mode for testing, monitor program execution, make incremental changes, and document all modifications to track issues effectively.

Simulation with 3D. Develope the 3D for equipment and kinetics enable for simulation and PLC login to simulate. PLC logic is to be followed accordingly as per the kinematic defined with 3D and process.