ABB Automation Builder for Temperature Control
Automation Builder provides ABB's unified environment for AC500 PLC programming, drive configuration, and HMI development. Built on CODESYS V3 with ABB-specific enhancements. Strength lies in seamless drive integration with ACS880 and other families....
Platform Strengths for Temperature Control:
- Excellent for robotics integration
- Strong in power and utilities
- Robust hardware for harsh environments
- Good scalability
Unique ${brand.software} Features:
- Integrated drive configuration for ACS880, ACS580 drives
- Extensive application libraries: HVAC, pumping, conveying, crane control
- Safety programming for AC500-S within standard project
- Panel Builder 600 HMI development integrated
Key Capabilities:
The Automation Builder environment excels at Temperature Control applications through its excellent for robotics integration. This is particularly valuable when working with the 4 sensor types typically found in Temperature Control systems, including Thermocouples (K-type, J-type), RTD sensors (PT100, PT1000), Infrared temperature sensors.
Control Equipment for Temperature Control:
- Electric resistance heaters (cartridge, band, strip)
- Steam injection systems
- Thermal fluid (hot oil) systems
- Refrigeration and chiller systems
ABB's controller families for Temperature Control include:
- AC500: Suitable for intermediate Temperature Control applications
- AC500-eCo: Suitable for intermediate Temperature Control applications
- AC500-S: Suitable for intermediate Temperature Control applications
Hardware Selection Guidance:
PM554 entry-level for simple applications. PM564 mid-range for OEM machines. PM573 high-performance for complex algorithms. PM5 series latest generation with cloud connectivity. AC500-S for integrated safety....
Industry Recognition:
Medium - Strong in power generation, mining, and marine applications. AC500 coordinating VFD-controlled motors with ACS880 drives. Energy optimization reducing consumption 25-40%. Robot integration via ABB robot interfaces. Press line automation with AC500-S safety....
Investment Considerations:
With $$ pricing, ABB positions itself in the mid-range segment. For Temperature Control projects requiring intermediate skill levels and 2-3 weeks development time, the total investment includes hardware, software licensing, training, and ongoing support.
Understanding Structured Text for Temperature Control
Structured Text (ST) is a high-level, text-based programming language defined in IEC 61131-3. It resembles Pascal and provides powerful constructs for complex algorithms, calculations, and data manipulation.
Execution Model:
Code executes sequentially from top to bottom within each program unit. Variables maintain state between scan cycles unless explicitly reset.
Core Advantages for Temperature Control:
- Powerful for complex logic: Critical for Temperature Control when handling intermediate control logic
- Excellent code reusability: Critical for Temperature Control when handling intermediate control logic
- Compact code representation: Critical for Temperature Control when handling intermediate control logic
- Good for algorithms and calculations: Critical for Temperature Control when handling intermediate control logic
- Familiar to software developers: Critical for Temperature Control when handling intermediate control logic
Why Structured Text Fits Temperature Control:
Temperature Control systems in Process Control typically involve:
- Sensors: RTDs (PT100/PT1000) for high-accuracy measurements, Thermocouples (J, K, T types) for high-temperature applications, Infrared pyrometers for non-contact measurement
- Actuators: SCR (thyristor) power controllers for electric heaters, Solid-state relays for on/off heating control, Proportional control valves for steam or thermal fluid
- Complexity: Intermediate with challenges including Long thermal time constants making tuning difficult
Control Strategies for Temperature Control:
- pid: Standard PID control with proportional, integral, and derivative terms tuned for the thermal process dynamics
- cascade: Master temperature loop outputs to slave heater/cooler control loop for tighter control
- ratio: Maintain temperature ratio between zones for gradient applications
Programming Fundamentals in Structured Text:
Variables:
- declaration: VAR / VAR_INPUT / VAR_OUTPUT / VAR_IN_OUT / VAR_GLOBAL sections
- initialization: Variables can be initialized at declaration: Counter : INT := 0;
- constants: VAR CONSTANT section for read-only values
Operators:
- arithmetic: + - * / MOD (modulo)
- comparison: = <> < > <= >=
- logical: AND OR XOR NOT
ControlStructures:
- if: IF condition THEN statements; ELSIF condition THEN statements; ELSE statements; END_IF;
- case: CASE selector OF value1: statements; value2: statements; ELSE statements; END_CASE;
- for: FOR index := start TO end BY step DO statements; END_FOR;
Best Practices for Structured Text:
- Use meaningful variable names with consistent naming conventions
- Initialize all variables at declaration to prevent undefined behavior
- Use enumerated types for state machines instead of magic numbers
- Break complex expressions into intermediate variables for readability
- Use functions for reusable calculations and function blocks for stateful operations
Common Mistakes to Avoid:
- Using = instead of := for assignment (= is comparison)
- Forgetting semicolons at end of statements
- Integer division truncation - use REAL for decimal results
- Infinite loops from incorrect WHILE/REPEAT conditions
Typical Applications:
1. PID control: Directly applicable to Temperature Control
2. Recipe management: Related control patterns
3. Statistical calculations: Related control patterns
4. Data logging: Related control patterns
Understanding these fundamentals prepares you to implement effective Structured Text solutions for Temperature Control using ABB Automation Builder.
Implementing Temperature Control with Structured Text
Industrial temperature control systems use PLCs to regulate process temperatures in manufacturing, food processing, chemical processing, and other applications. These systems maintain precise temperature setpoints through heating and cooling control while ensuring product quality and energy efficiency.
This walkthrough demonstrates practical implementation using ABB Automation Builder and Structured Text programming.
System Requirements:
A typical Temperature Control implementation includes:
Input Devices (Sensors):
1. RTDs (PT100/PT1000) for high-accuracy measurements: Critical for monitoring system state
2. Thermocouples (J, K, T types) for high-temperature applications: Critical for monitoring system state
3. Infrared pyrometers for non-contact measurement: Critical for monitoring system state
4. Thermistors for fast response applications: Critical for monitoring system state
5. Thermal imaging cameras for surface temperature monitoring: Critical for monitoring system state
Output Devices (Actuators):
1. SCR (thyristor) power controllers for electric heaters: Primary control output
2. Solid-state relays for on/off heating control: Supporting control function
3. Proportional control valves for steam or thermal fluid: Supporting control function
4. Solenoid valves for cooling water or refrigerant: Supporting control function
5. Variable frequency drives for cooling fan control: Supporting control function
Control Equipment:
- Electric resistance heaters (cartridge, band, strip)
- Steam injection systems
- Thermal fluid (hot oil) systems
- Refrigeration and chiller systems
Control Strategies for Temperature Control:
- pid: Standard PID control with proportional, integral, and derivative terms tuned for the thermal process dynamics
- cascade: Master temperature loop outputs to slave heater/cooler control loop for tighter control
- ratio: Maintain temperature ratio between zones for gradient applications
Implementation Steps:
Step 1: Characterize thermal system dynamics (time constants, dead time)
In Automation Builder, characterize thermal system dynamics (time constants, dead time).
Step 2: Select appropriate sensor type and placement for representative measurement
In Automation Builder, select appropriate sensor type and placement for representative measurement.
Step 3: Size heating and cooling capacity for worst-case load conditions
In Automation Builder, size heating and cooling capacity for worst-case load conditions.
Step 4: Implement PID control with appropriate sample time (typically 10x faster than process time constant)
In Automation Builder, implement pid control with appropriate sample time (typically 10x faster than process time constant).
Step 5: Add output limiting and anti-windup for safe operation
In Automation Builder, add output limiting and anti-windup for safe operation.
Step 6: Program ramp/soak profiles if required
In Automation Builder, program ramp/soak profiles if required.
ABB Function Design:
Standard FB structure with VAR_INPUT/OUTPUT/VAR. Methods extend functionality. ABB application libraries provide tested FBs. Drive FBs wrap drive parameter access.
Common Challenges and Solutions:
1. Long thermal time constants making tuning difficult
- Solution: Structured Text addresses this through Powerful for complex logic.
2. Transport delay (dead time) causing instability
- Solution: Structured Text addresses this through Excellent code reusability.
3. Non-linear response at different temperature ranges
- Solution: Structured Text addresses this through Compact code representation.
4. Sensor placement affecting measurement accuracy
- Solution: Structured Text addresses this through Good for algorithms and calculations.
Safety Considerations:
- Independent high-limit safety thermostats (redundant to PLC)
- Watchdog timers for heater control validity
- Safe-state definition on controller failure (heaters off)
- Thermal fuse backup for runaway conditions
- Proper ventilation for combustible atmospheres
Performance Metrics:
- Scan Time: Optimize for 4 inputs and 5 outputs
- Memory Usage: Efficient data structures for AC500 capabilities
- Response Time: Meeting Process Control requirements for Temperature Control
ABB Diagnostic Tools:
Online monitoring with live values,Watch window with expressions,Breakpoints for inspection,Drive diagnostics showing fault history,Communication diagnostics for network statistics
ABB's Automation Builder provides tools for performance monitoring and optimization, essential for achieving the 2-3 weeks development timeline while maintaining code quality.
ABB Structured Text Example for Temperature Control
Complete working example demonstrating Structured Text implementation for Temperature Control using ABB Automation Builder. Follows ABB naming conventions. Tested on AC500 hardware.
(* ABB Automation Builder - Temperature Control Control *)
(* Structured Text Implementation for Process Control *)
(* g_ prefix for globals. i_/q_ for FB I/O. Type prefixes: b=BOOL, n=INT, *)
PROGRAM PRG_TEMPERATURE_CONTROL_Control
VAR
(* State Machine Variables *)
eState : E_TEMPERATURE_CONTROL_States := IDLE;
bEnable : BOOL := FALSE;
bFaultActive : BOOL := FALSE;
(* Timers *)
tonDebounce : TON;
tonProcessTimeout : TON;
tonFeedbackCheck : TON;
(* Counters *)
ctuCycleCounter : CTU;
(* Process Variables *)
rThermocouplesKtypeJtype : REAL := 0.0;
rHeatingelements : REAL := 0.0;
rSetpoint : REAL := 100.0;
END_VAR
VAR CONSTANT
(* Process Control Process Parameters *)
C_DEBOUNCE_TIME : TIME := T#500MS;
C_PROCESS_TIMEOUT : TIME := T#30S;
C_BATCH_SIZE : INT := 50;
END_VAR
(* Input Conditioning *)
tonDebounce(IN := bStartButton, PT := C_DEBOUNCE_TIME);
bEnable := tonDebounce.Q AND NOT bEmergencyStop AND bSafetyOK;
(* Main State Machine - Pattern: CASE eState OF IDLE: IF bStartCmd THEN e *)
CASE eState OF
IDLE:
rHeatingelements := 0.0;
ctuCycleCounter(RESET := TRUE);
IF bEnable AND rThermocouplesKtypeJtype > 10.0 THEN
eState := STARTING;
END_IF;
STARTING:
(* Ramp up output - Gradual start *)
rHeatingelements := MIN(rHeatingelements + 5.0, rSetpoint);
IF rHeatingelements >= rSetpoint THEN
eState := RUNNING;
END_IF;
RUNNING:
(* Temperature Control active - Industrial temperature control systems use PLCs to *)
tonProcessTimeout(IN := TRUE, PT := C_PROCESS_TIMEOUT);
ctuCycleCounter(CU := bCyclePulse, PV := C_BATCH_SIZE);
IF ctuCycleCounter.Q THEN
eState := COMPLETE;
ELSIF tonProcessTimeout.Q THEN
bFaultActive := TRUE;
eState := FAULT;
END_IF;
COMPLETE:
rHeatingelements := 0.0;
(* Log production data - Circular buffer with ST_LogRecord. Write index with modulo wrap. Triggered capture with pre/post samples. File export using file system library. *)
eState := IDLE;
FAULT:
rHeatingelements := 0.0;
(* ST_Alarm structure with bActive, bAcknowledged, dtActivation, nCode, sMessage. Array of alarms with detection and acknowledgment logic. Integration with ABB alarm libraries. *)
IF bFaultReset AND NOT bEmergencyStop THEN
bFaultActive := FALSE;
eState := IDLE;
END_IF;
END_CASE;
(* Safety Override - Always executes *)
IF bEmergencyStop OR NOT bSafetyOK THEN
rHeatingelements := 0.0;
eState := FAULT;
bFaultActive := TRUE;
END_IF;
END_PROGRAMCode Explanation:
- 1.Enumerated state machine (CASE eState OF IDLE: IF bStartCmd THEN eState := STARTING; END_IF; STARTING: tonStarting(IN := TRUE, PT := T#10S); IF bRunConfirm THEN eState := RUNNING; END_IF; END_CASE; Log transitions.) for clear Temperature Control sequence control
- 2.Constants define Process Control-specific parameters: cycle time 30s, batch size
- 3.Input conditioning with debounce timer prevents false triggers in industrial environment
- 4.STARTING state implements soft-start ramp - prevents mechanical shock
- 5.Process timeout detection identifies stuck conditions - critical for reliability
- 6.Safety override section executes regardless of state - ABB best practice for intermediate systems
Best Practices
- ✓Follow ABB naming conventions: g_ prefix for globals. i_/q_ for FB I/O. Type prefixes: b=BOOL, n=INT, r=REAL, s
- ✓ABB function design: Standard FB structure with VAR_INPUT/OUTPUT/VAR. Methods extend functionality. A
- ✓Data organization: DUTs define structures. GVLs group related data. Retain attribute preserves vari
- ✓Structured Text: Use meaningful variable names with consistent naming conventions
- ✓Structured Text: Initialize all variables at declaration to prevent undefined behavior
- ✓Structured Text: Use enumerated types for state machines instead of magic numbers
- ✓Temperature Control: Sample at 1/10 of the process time constant minimum
- ✓Temperature Control: Use derivative on PV, not error, for temperature control
- ✓Temperature Control: Start with conservative tuning and tighten gradually
- ✓Debug with Automation Builder: Use structured logging to controller log
- ✓Safety: Independent high-limit safety thermostats (redundant to PLC)
- ✓Use Automation Builder simulation tools to test Temperature Control logic before deployment
Common Pitfalls to Avoid
- ⚠Structured Text: Using = instead of := for assignment (= is comparison)
- ⚠Structured Text: Forgetting semicolons at end of statements
- ⚠Structured Text: Integer division truncation - use REAL for decimal results
- ⚠ABB common error: Exception 'AccessViolation': Null pointer access
- ⚠Temperature Control: Long thermal time constants making tuning difficult
- ⚠Temperature Control: Transport delay (dead time) causing instability
- ⚠Neglecting to validate RTDs (PT100/PT1000) for high-accuracy measurements leads to control errors
- ⚠Insufficient comments make Structured Text programs unmaintainable over time