Automated Cement Plant Process Control using Siemens TIA Portal & HMI

Technical Breakdown:

1. PLC Architecture & Analog Processing (CPU 314C-2 PN/DP):

Signal Conditioning: Implemented FC2 Scaling Sensors using the SCALE_X function to convert raw analog input integers (IW3, IW5, etc.) into precise Floating Point (Real) engineering units (0.0 - 1000.0 kg) for the Limestone, Clay, and Water tanks.

Dynamic Limit Calculation: Unlike simple static limits, I used Math blocks (ADD) in FC5 Alarms to dynamically calculate "OverLimit" thresholds (e.g., Setpoint + Tolerance). If the Actual Weight exceeds this calculated value, a warning bit is triggered immediately.

2. Complex Logic Mechanism (FC3 Process):

Sequential Batching Logic: The process relies on a robust sequence of Comparator Operations (CMP ). For example, the logic continuously compares Actual Weight against the Target Limit. As long as the weight is below the setpoint, the specific Pump and Feeding Valve remain active.

Precision Discharge Control: I utilized Comparator Logic (CMP ) to manage the discharge phase. The valves automatically close only when the tank weight drops below a specific residual value (e.g., 0.2 kg), ensuring the tanks are fully evacuated before the next cycle begins.

Timer Integration: Integrated S_ODT (Stored On-Delay Timers) to control the mixing phase, ensuring precise blending times before the final discharge valve (Q1.4) is allowed to open.

3. Safety & Alarm System:

Latch/Unlatch Logic: I designed the alarm system using Set/Reset (SR) latches. If a critical fault occurs (like "Overload 4"), the alarm bit (M11.3) is LATCHED and holds the system in a stop state until the operator explicitly presses the "RESET Alarm" button on the HMI.

Interlocks: Critical pumps are hard-interlocked. If an Overload bit is high, the logic physically cuts the output to the motor coil, preventing hardware damage.

4. HMI Engineering (TP2200 Comfort):

Recipe Management: Designed a flexible Recipe screen allowing operators to adjust batch parameters for various cement grades on the fly.

Visual Feedback: The Main Screen features dynamic animations linked to the PLC tags, giving operators real-time situational awareness of tank levels and valve states.

This project sharpened my skills in LAD programming, analog signal processing, and defining complex control algorithms.

#Siemens #TIAPortal #Automation #PLC #HMI #IndustrialAutomation #LadderLogic #ProcessControl #Engineering #Scada