Simulateur Modbus - Documentation
Traditional Modbus tools — applications like Modbus Poll Slave — serve a specific and valuable purpose: they let you manually create virtual Modbus devices by entering register values into tables. This is useful for basic connectivity testing and for verifying that your SCADA system can read Modbus registers.
But these tools operate at the protocol level. They simulate Modbus communication, not system behavior. You manually enter a temperature value of 87.5°C into register 100, and your SCADA reads that fixed value. The value never changes. There is no start-up ramp. No response to demand changes. No thermal dynamics. No state transitions.
The Modbus System Simulator takes a fundamentally different approach.
Figure 2 — Traditional Modbus tools focus on static register values; System Simulation creates a complete, dynamic digital copy of the real installation
|
Aspect |
Traditional Modbus Tool |
Modbus System Simulator |
|
Focus |
Protocol — registers, data types |
System — compressors, environment, behavior |
|
Data |
Manually entered, static values |
Learned from real operational logs |
|
Behavior |
Fixed register values |
Dynamic state machine with 6 states |
|
Uniqueness |
Generic |
Each simulation is trained from YOUR system |
|
Startup/Stop |
Not simulated |
Realistic ramp profiles from real data |
|
Faults |
Manual register write |
Condition-based triggers with realistic responses |
|
Environment |
Not represented |
I/O module + compressor sensors capture full context |
|
Use case |
Quick connectivity check |
Full system development, testing, and training |
The critical difference: when your SCADA connects to a traditional Modbus tool, it sees a collection of numbers. When it connects to the Modbus System Simulator, it sees a living compressor that starts up, runs, responds to load changes, faults, and shuts down — all with the timing and dynamics of your real system.
How It Works — The Digital Twin
A system simulation is only as good as the system model it contains. The Modbus System Simulator builds its model from three sources of knowledge: the compressor itself, the I/O module, and the training data that captures how they all interact.
3.1 The Compressor: Executor and Sensor in One
The compressor is the heart of any HVAC system, and it plays a dual role that is essential to understand:
Figure 3 — The compressor acts simultaneously as the system's executor (controlling the HVAC process) and as its most comprehensive sensor (measuring pressures, temperatures, speeds, and fault conditions)
As an Executor
The compressor is the principal device that controls the HVAC process. It responds to demand signals, adjusts speed and power, manages inlet guide vane position, and controls interlock states. When your control system says 'deliver 75% cooling capacity,' the compressor translates that into physical action — RPM changes, power draw, refrigerant flow.
As a Sensor
The compressor is simultaneously the most comprehensive measurement device in the system. It reports suction pressure and temperature, discharge pressure and temperature, motor current, DC bus voltage, inverter temperature, cavity temperature, surge and choke speed limits, and detailed fault status across multiple registers. No other single device in the HVAC system provides this breadth of process feedback.
This dual role means that simulating a compressor accurately requires simulating the entire system context. A compressor's discharge temperature does not exist in isolation — it depends on suction conditions, ambient temperature, demand level, refrigerant type, piping losses, and dozens of other factors. A credible digital twin must capture all of these relationships, and that is exactly what the training process does.
3.2 The I/O Module: Measuring the Environment
The I/O Module represents the external environmental conditions that surround the compressor. In a real installation, these I/O signals provide the environmental context that drives compressor behavior: external air temperature, water flow switches, safety interlocks, set-point signals, and more.
In the Modbus System Simulator, the I/O Module provides 64 channels:
|
Channel Type |
Count |
Role in the System |
|
Digital Inputs (DI) |
24 |
Safety interlocks, flow switches, run permissives |
|
Digital Outputs (DO) |
12 |
Valve commands, fan controls, indicator outputs |
|
Analog Inputs (AI) |
8 |
External temperatures, pressures, humidity levels |
|
Analog Outputs (AO) |
12 |
Set-point outputs, control signals |
|
Temperature Inputs (TI) |
8 |
Water supply/return temps, air-side temperatures |
These channels represent the boundary conditions that determine how the compressor operates. A compressor starting at 35°C ambient behaves differently from one starting at 5°C — different start-up profiles, different steady-state pressures, different efficiency curves. By including the I/O environment in the simulation, the digital twin captures these contextual dependencies.
3.3 System Interactions
In a real HVAC system, nothing happens in isolation. The compressor reads the environment (through its own sensors and the I/O module), adjusts its operation, and the results feed back into the environment. The system is a closed loop.
The Modbus System Simulator preserves these interactions in its digital twin. When training data includes coordinated logs from both the I/O module and the compressor, the trained tables capture the real-world correlations: when suction temperature rises, how does discharge pressure respond? When demand drops from 80% to 20%, how fast do temperatures change? These relationships are not programmed by an engineer — they are learned from the actual operational data of the specific installation.
This is what makes each digital twin unique. Two identical TTS300 compressors installed in different buildings will behave differently because the systems they serve are different. The Modbus System Simulator captures that uniqueness.
Traditional Modbus tools — applications like Modbus Poll Slave — serve a specific and valuable purpose: they let you manually create virtual Modbus devices by entering register values into tables. This is useful for basic connectivity testing and for verifying that your SCADA system can read Modbus registers.
But these tools operate at the protocol level. They simulate Modbus communication, not system behavior. You manually enter a temperature value of 87.5°C into register 100, and your SCADA reads that fixed value. The value never changes. There is no start-up ramp. No response to demand changes. No thermal dynamics. No state transitions.
The Modbus System Simulator takes a fundamentally different approach.
Figure 2 — Traditional Modbus tools focus on static register values; System Simulation creates a complete, dynamic digital copy of the real installation
|
Aspect |
Traditional Modbus Tool |
Modbus System Simulator |
|
Focus |
Protocol — registers, data types |
System — compressors, environment, behavior |
|
Data |
Manually entered, static values |
Learned from real operational logs |
|
Behavior |
Fixed register values |
Dynamic state machine with 6 states |
|
Uniqueness |
Generic |
Each simulation is trained from YOUR system |
|
Startup/Stop |
Not simulated |
Realistic ramp profiles from real data |
|
Faults |
Manual register write |
Condition-based triggers with realistic responses |
|
Environment |
Not represented |
I/O module + compressor sensors capture full context |
|
Use case |
Quick connectivity check |
Full system development, testing, and training |
The critical difference: when your SCADA connects to a traditional Modbus tool, it sees a collection of numbers. When it connects to the Modbus System Simulator, it sees a living compressor that starts up, runs, responds to load changes, faults, and shuts down — all with the timing and dynamics of your real system.
How It Works — The Digital Twin
A system simulation is only as good as the system model it contains. The Modbus System Simulator builds its model from three sources of knowledge: the compressor itself, the I/O module, and the training data that captures how they all interact.
3.1 The Compressor: Executor and Sensor in One
The compressor is the heart of any HVAC system, and it plays a dual role that is essential to understand:
Figure 3 — The compressor acts simultaneously as the system's executor (controlling the HVAC process) and as its most comprehensive sensor (measuring pressures, temperatures, speeds, and fault conditions)
As an Executor
The compressor is the principal device that controls the HVAC process. It responds to demand signals, adjusts speed and power, manages inlet guide vane position, and controls interlock states. When your control system says 'deliver 75% cooling capacity,' the compressor translates that into physical action — RPM changes, power draw, refrigerant flow.
As a Sensor
The compressor is simultaneously the most comprehensive measurement device in the system. It reports suction pressure and temperature, discharge pressure and temperature, motor current, DC bus voltage, inverter temperature, cavity temperature, surge and choke speed limits, and detailed fault status across multiple registers. No other single device in the HVAC system provides this breadth of process feedback.
This dual role means that simulating a compressor accurately requires simulating the entire system context. A compressor's discharge temperature does not exist in isolation — it depends on suction conditions, ambient temperature, demand level, refrigerant type, piping losses, and dozens of other factors. A credible digital twin must capture all of these relationships, and that is exactly what the training process does.
3.2 The I/O Module: Measuring the Environment
The I/O Module represents the external environmental conditions that surround the compressor. In a real installation, these I/O signals provide the environmental context that drives compressor behavior: external air temperature, water flow switches, safety interlocks, set-point signals, and more.
In the Modbus System Simulator, the I/O Module provides 64 channels:
|
Channel Type |
Count |
Role in the System |
|
Digital Inputs (DI) |
24 |
Safety interlocks, flow switches, run permissives |
|
Digital Outputs (DO) |
12 |
Valve commands, fan controls, indicator outputs |
|
Analog Inputs (AI) |
8 |
External temperatures, pressures, humidity levels |
|
Analog Outputs (AO) |
12 |
Set-point outputs, control signals |
|
Temperature Inputs (TI) |
8 |
Water supply/return temps, air-side temperatures |
These channels represent the boundary conditions that determine how the compressor operates. A compressor starting at 35°C ambient behaves differently from one starting at 5°C — different start-up profiles, different steady-state pressures, different efficiency curves. By including the I/O environment in the simulation, the digital twin captures these contextual dependencies.
3.3 System Interactions
In a real HVAC system, nothing happens in isolation. The compressor reads the environment (through its own sensors and the I/O module), adjusts its operation, and the results feed back into the environment. The system is a closed loop.
The Modbus System Simulator preserves these interactions in its digital twin. When training data includes coordinated logs from both the I/O module and the compressor, the trained tables capture the real-world correlations: when suction temperature rises, how does discharge pressure respond? When demand drops from 80% to 20%, how fast do temperatures change? These relationships are not programmed by an engineer — they are learned from the actual operational data of the specific installation.
This is what makes each digital twin unique. Two identical TTS300 compressors installed in different buildings will behave differently because the systems they serve are different. The Modbus System Simulator captures that uniqueness.
Traditional Modbus tools — applications like Modbus Poll Slave — serve a specific and valuable purpose: they let you manually create virtual Modbus devices by entering register values into tables. This is useful for basic connectivity testing and for verifying that your SCADA system can read Modbus registers.
But these tools operate at the protocol level. They simulate Modbus communication, not system behavior. You manually enter a temperature value of 87.5°C into register 100, and your SCADA reads that fixed value. The value never changes. There is no start-up ramp. No response to demand changes. No thermal dynamics. No state transitions.
The Modbus System Simulator takes a fundamentally different approach.
Figure 2 — Traditional Modbus tools focus on static register values; System Simulation creates a complete, dynamic digital copy of the real installation
|
Aspect |
Traditional Modbus Tool |
Modbus System Simulator |
|
Focus |
Protocol — registers, data types |
System — compressors, environment, behavior |
|
Data |
Manually entered, static values |
Learned from real operational logs |
|
Behavior |
Fixed register values |
Dynamic state machine with 6 states |
|
Uniqueness |
Generic |
Each simulation is trained from YOUR system |
|
Startup/Stop |
Not simulated |
Realistic ramp profiles from real data |
|
Faults |
Manual register write |
Condition-based triggers with realistic responses |
|
Environment |
Not represented |
I/O module + compressor sensors capture full context |
|
Use case |
Quick connectivity check |
Full system development, testing, and training |
The critical difference: when your SCADA connects to a traditional Modbus tool, it sees a collection of numbers. When it connects to the Modbus System Simulator, it sees a living compressor that starts up, runs, responds to load changes, faults, and shuts down — all with the timing and dynamics of your real system.
How It Works — The Digital Twin
A system simulation is only as good as the system model it contains. The Modbus System Simulator builds its model from three sources of knowledge: the compressor itself, the I/O module, and the training data that captures how they all interact.
3.1 The Compressor: Executor and Sensor in One
The compressor is the heart of any HVAC system, and it plays a dual role that is essential to understand:
Figure 3 — The compressor acts simultaneously as the system's executor (controlling the HVAC process) and as its most comprehensive sensor (measuring pressures, temperatures, speeds, and fault conditions)
As an Executor
The compressor is the principal device that controls the HVAC process. It responds to demand signals, adjusts speed and power, manages inlet guide vane position, and controls interlock states. When your control system says 'deliver 75% cooling capacity,' the compressor translates that into physical action — RPM changes, power draw, refrigerant flow.
As a Sensor
The compressor is simultaneously the most comprehensive measurement device in the system. It reports suction pressure and temperature, discharge pressure and temperature, motor current, DC bus voltage, inverter temperature, cavity temperature, surge and choke speed limits, and detailed fault status across multiple registers. No other single device in the HVAC system provides this breadth of process feedback.
This dual role means that simulating a compressor accurately requires simulating the entire system context. A compressor's discharge temperature does not exist in isolation — it depends on suction conditions, ambient temperature, demand level, refrigerant type, piping losses, and dozens of other factors. A credible digital twin must capture all of these relationships, and that is exactly what the training process does.
3.2 The I/O Module: Measuring the Environment
The I/O Module represents the external environmental conditions that surround the compressor. In a real installation, these I/O signals provide the environmental context that drives compressor behavior: external air temperature, water flow switches, safety interlocks, set-point signals, and more.
In the Modbus System Simulator, the I/O Module provides 64 channels:
|
Channel Type |
Count |
Role in the System |
|
Digital Inputs (DI) |
24 |
Safety interlocks, flow switches, run permissives |
|
Digital Outputs (DO) |
12 |
Valve commands, fan controls, indicator outputs |
|
Analog Inputs (AI) |
8 |
External temperatures, pressures, humidity levels |
|
Analog Outputs (AO) |
12 |
Set-point outputs, control signals |
|
Temperature Inputs (TI) |
8 |
Water supply/return temps, air-side temperatures |
These channels represent the boundary conditions that determine how the compressor operates. A compressor starting at 35°C ambient behaves differently from one starting at 5°C — different start-up profiles, different steady-state pressures, different efficiency curves. By including the I/O environment in the simulation, the digital twin captures these contextual dependencies.
3.3 System Interactions
In a real HVAC system, nothing happens in isolation. The compressor reads the environment (through its own sensors and the I/O module), adjusts its operation, and the results feed back into the environment. The system is a closed loop.
The Modbus System Simulator preserves these interactions in its digital twin. When training data includes coordinated logs from both the I/O module and the compressor, the trained tables capture the real-world correlations: when suction temperature rises, how does discharge pressure respond? When demand drops from 80% to 20%, how fast do temperatures change? These relationships are not programmed by an engineer — they are learned from the actual operational data of the specific installation.
This is what makes each digital twin unique. Two identical TTS300 compressors installed in different buildings will behave differently because the systems they serve are different. The Modbus System Simulator captures that uniqueness.
Traditional Modbus tools — applications like Modbus Poll Slave — serve a specific and valuable purpose: they let you manually create virtual Modbus devices by entering register values into tables. This is useful for basic connectivity testing and for verifying that your SCADA system can read Modbus registers.
But these tools operate at the protocol level. They simulate Modbus communication, not system behavior. You manually enter a temperature value of 87.5°C into register 100, and your SCADA reads that fixed value. The value never changes. There is no start-up ramp. No response to demand changes. No thermal dynamics. No state transitions.
The Modbus System Simulator takes a fundamentally different approach.
Figure 2 — Traditional Modbus tools focus on static register values; System Simulation creates a complete, dynamic digital copy of the real installation
|
Aspect |
Traditional Modbus Tool |
Modbus System Simulator |
|
Focus |
Protocol — registers, data types |
System — compressors, environment, behavior |
|
Data |
Manually entered, static values |
Learned from real operational logs |
|
Behavior |
Fixed register values |
Dynamic state machine with 6 states |
|
Uniqueness |
Generic |
Each simulation is trained from YOUR system |
|
Startup/Stop |
Not simulated |
Realistic ramp profiles from real data |
|
Faults |
Manual register write |
Condition-based triggers with realistic responses |
|
Environment |
Not represented |
I/O module + compressor sensors capture full context |
|
Use case |
Quick connectivity check |
Full system development, testing, and training |
The critical difference: when your SCADA connects to a traditional Modbus tool, it sees a collection of numbers. When it connects to the Modbus System Simulator, it sees a living compressor that starts up, runs, responds to load changes, faults, and shuts down — all with the timing and dynamics of your real system.
How It Works — The Digital Twin
A system simulation is only as good as the system model it contains. The Modbus System Simulator builds its model from three sources of knowledge: the compressor itself, the I/O module, and the training data that captures how they all interact.
3.1 The Compressor: Executor and Sensor in One
The compressor is the heart of any HVAC system, and it plays a dual role that is essential to understand:
Figure 3 — The compressor acts simultaneously as the system's executor (controlling the HVAC process) and as its most comprehensive sensor (measuring pressures, temperatures, speeds, and fault conditions)
As an Executor
The compressor is the principal device that controls the HVAC process. It responds to demand signals, adjusts speed and power, manages inlet guide vane position, and controls interlock states. When your control system says 'deliver 75% cooling capacity,' the compressor translates that into physical action — RPM changes, power draw, refrigerant flow.
As a Sensor
The compressor is simultaneously the most comprehensive measurement device in the system. It reports suction pressure and temperature, discharge pressure and temperature, motor current, DC bus voltage, inverter temperature, cavity temperature, surge and choke speed limits, and detailed fault status across multiple registers. No other single device in the HVAC system provides this breadth of process feedback.
This dual role means that simulating a compressor accurately requires simulating the entire system context. A compressor's discharge temperature does not exist in isolation — it depends on suction conditions, ambient temperature, demand level, refrigerant type, piping losses, and dozens of other factors. A credible digital twin must capture all of these relationships, and that is exactly what the training process does.
3.2 The I/O Module: Measuring the Environment
The I/O Module represents the external environmental conditions that surround the compressor. In a real installation, these I/O signals provide the environmental context that drives compressor behavior: external air temperature, water flow switches, safety interlocks, set-point signals, and more.
In the Modbus System Simulator, the I/O Module provides 64 channels:
|
Channel Type |
Count |
Role in the System |
|
Digital Inputs (DI) |
24 |
Safety interlocks, flow switches, run permissives |
|
Digital Outputs (DO) |
12 |
Valve commands, fan controls, indicator outputs |
|
Analog Inputs (AI) |
8 |
External temperatures, pressures, humidity levels |
|
Analog Outputs (AO) |
12 |
Set-point outputs, control signals |
|
Temperature Inputs (TI) |
8 |
Water supply/return temps, air-side temperatures |
These channels represent the boundary conditions that determine how the compressor operates. A compressor starting at 35°C ambient behaves differently from one starting at 5°C — different start-up profiles, different steady-state pressures, different efficiency curves. By including the I/O environment in the simulation, the digital twin captures these contextual dependencies.
3.3 System Interactions
In a real HVAC system, nothing happens in isolation. The compressor reads the environment (through its own sensors and the I/O module), adjusts its operation, and the results feed back into the environment. The system is a closed loop.
The Modbus System Simulator preserves these interactions in its digital twin. When training data includes coordinated logs from both the I/O module and the compressor, the trained tables capture the real-world correlations: when suction temperature rises, how does discharge pressure respond? When demand drops from 80% to 20%, how fast do temperatures change? These relationships are not programmed by an engineer — they are learned from the actual operational data of the specific installation.
This is what makes each digital twin unique. Two identical TTS300 compressors installed in different buildings will behave differently because the systems they serve are different. The Modbus System Simulator captures that uniqueness.
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