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Interface Specification Modbus Parameter Specification for External Bus Communication of the Güntner Motor Management EC (GMM EC) Version 1.0.7-EC(English) Güntner AG & Co. KG Controls Development Güntner AG & Co. KG Hans-Güntner-Straße 2-6 82256 Fürstenfeldbruck Phone: +49 8141/242-0 Email: info@guentner.de

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Table of Contents Revision History...............................................................................................................................................................................4 Introduction.......................................................................................................................................................................................5 1 Protocol Frame .......................................................................................................................................................................6

1.1 Interface parameters................................................................................................................................................6 1.2 Communication process.........................................................................................................................................6

1.2.1 Answer of the GMM.............................................................................................................................................8 1.3 Data Bytes ....................................................................................................................................................................9

1.3.1 Read Holding Register........................................................................................................................................9 1.3.2 Read Input Register..........................................................................................................................................10 1.3.3 Write Single Register........................................................................................................................................11 1.3.4 Read Multiple Register ....................................................................................................................................11

2 Register ...................................................................................................................................................................................12 2.1 Overview .....................................................................................................................................................................12 2.2 Holding Register......................................................................................................................................................13

2.2.1 Control Value.......................................................................................................................................................13 2.2.2 Operating Mode .................................................................................................................................................13

2.2.2.1 Automatic internal ..................................................................................................................................13 2.2.2.2 Automatic external analog ..................................................................................................................13 2.2.2.3 Automatic external bus ........................................................................................................................13 2.2.2.4 Slave external analog ............................................................................................................................14 2.2.2.5 Slave external bus ..................................................................................................................................14

2.2.3 Control Parameter Kp1...................................................................................................................................14 2.2.4 Control Parameter Ti1.....................................................................................................................................16 2.2.5 Control Parameter Td1 ...................................................................................................................................16 2.2.6 Control Parameter Kp2 (not yet implemented)....................................................................................17 2.2.7 Control Parameter Ti2 (not yet implemented)......................................................................................17 2.2.8 Control Parameter Td2 (not yet implemented)....................................................................................17 2.2.9 Switching Control System (not yet implemented)...............................................................................17 2.2.10 Setpoint 1........................................................................................................................................................18 2.2.11 Setpoint 2........................................................................................................................................................18 2.2.12 Watchdog.........................................................................................................................................................20 2.2.13 Used Refrigerant...........................................................................................................................................20 2.2.14 Modbus Address...........................................................................................................................................21

2.3 Input Registers.........................................................................................................................................................22 2.3.1 Number of Motors of the GMM EC ............................................................................................................22 2.3.2 State of the digital inputs of the GMM .....................................................................................................23 2.3.3 Function current input AI1 (4 .. 20 mA) ..................................................................................................24 2.3.4 Raw Value AI1 .....................................................................................................................................................25 2.3.5 AI1 Scaled Value (depending on the selected refrigerant) ..............................................................25 2.3.6 Function current input AI2 (4..20mA).......................................................................................................27 2.3.7 Raw Value AI2 .....................................................................................................................................................27 2.3.8 AI2 Scaled Value (depending on the selected refrigerant) ..............................................................29 2.3.9 Function Resistance Input .............................................................................................................................30 2.3.10 Resistor Input / Raw Value (not yet implemented) .......................................................................30 2.3.11 Scaled Value AI3 (GTF210)......................................................................................................................31 2.3.12 Function Voltage Input (0..10V) .............................................................................................................32 2.3.13 Voltage Input AI4 (0..10V) / Raw Value...............................................................................................33 2.3.14 Voltage Input AI4, Scaled Value .............................................................................................................33 2.3.15 Status Manual Mode...................................................................................................................................34 2.3.16 Control Value Manual Mode ....................................................................................................................35 2.3.17 Type of Motorcontrol (ECC, SinCon, PhaseCut etc.) ......................................................................35 2.3.18 Current Energy Consumption of one Motor or in total ................................................................37 2.3.19 Motor temperature (only for GMM EC)...............................................................................................38 2.3.20 Current Fan Speed (in rpm) ....................................................................................................................39 2.3.21 Errors / Alarms of the GMM....................................................................................................................40 2.3.22 Errors / Alarms of the GMM EC .............................................................................................................40

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2.3.23 Thermal Output ............................................................................................................................................41 2.3.24 Current Fanspeed as percentage of the Maximum Speed.........................................................41 2.3.25 Current Air Volume as percentage of the Maximum Air Volume.............................................42

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Revision History Version Datum Autor Status V1.00 10.05.2010 T.Wallrabenstein First english version of this document V1.01 9.6.2010 T.Wallrabenstein 3.3.17 The read value is not multiplied by 10 V1.01 27.07.2010 T.Wallrabenstein Added:

3.2.14 Modbus Address 3.3.22 Current Air Volume as percentage of the maximum air volume

V1.02 28.07.2010 T.Wallrabenstein Format of the Table of Contents Wrong value in example (in 3.2.1 Control Value)

V1.03 23.08.2010 T.Wallrabenstein Wrong value in example (in 3.2.4 Control Parameter Ti1) Wrong value in example (in 3.2.5 Control Parameter Td1)

V1.04 16.09.2010 T.Wallrabenstein Added: Register D10F: Type of Motorcontrol Added: Chapter 2.3.21 Errors / Alarms of the

GMM SinCon Added:

Register D105: Value 5 – outdoor temperature Register D108: Value 5 - outdoor temperature

Added: Refrigerant R22 in chapter 2.2.13 Seperated chapter 2.3.20 in Errors / Alarms

of the GMM …..EC and …..SinCon Extended chapter 2.3.1 with frequency

converters of the GMM 21.09.2010 Added „The register range depends on the

number of connected frequency converters.” in all chapters which describe registers using a register range depending on the number of motors

23.09.2010 Changed the table in chapter 2.3.23: Operating hours counter has now 2 bytes (byte 6,7), the fault location is now in byte 5 Added Bit 0 in table Warnings

V1.05 23.11.2010 Marked all values as hexadecimal values V1.05-EC V1.05-sincon

13.12.2010 Separate specs for GMM EC and GMM sincon

V1.07-EC 20.09.2011 Added Modbus address New sincon functions (Firmware V10)

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Introduction This document specifies the Modbus Parameters of the Güntner Motor Management (GMM) system produced by the Güntner AG & Co. KG. Knowledge of the general Modbus Specification is assumed: - MODBUS over Serial Line Specification & Implementation guide V1.0 - MODBUS Application Protocol Specification V1.1 These documents are available on the internet at modbus.org The above-mentioned Modbus specification forms the basis of this document and has full validity, except for the restrictions described in this document. The GMM can receive data from an external master controller (Modbus). Additionally information is available concerning the modbus interface (e.g. motor temperature, actual speed etc.). The master controller sends information, such as: - Setpoint 1 in bar or temperature - operating mode - control value

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1 Protocol Frame The data transfer defined in this specification will only work in a Master-Slave Environment. The data transfer is controlled by the master, the GMM is always modbus slave. A twisted pair cable has to be used for data communication (RS485 standard). Only the RTU transmission mode will be supported (see MODBUS over Serial Line Specification & Implementation guide V1.0, Chapter 2.5.1)

1.1 Interface parameters Following interface parameters will be supported: RS485 Standard (Modbus RTU) 9600 Baud (8 Databits, No Parity, 1 Stopbit) Line termination: 120 ohms at each side of the link, in parallel These parameters must be used by all members on the bus.

1.2 Communication process MODBUS over Serial Line Specification & Implementation guide V1.0 defines following communication process: Start Address Function

Code Data CRC

Lowbyte CRC Highbyte

Command >3.5 char 8 bits 8 bits N * 8 bits 8 bits 8 bits Answer >3.5 char 8 bits 8 bits N * 8 bits 8 bits 8 bits

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Command from Master Address: The address field has a size of 8 bits. Address range: 0..247 The address 0 is for broadcast messages (a message which will be received by all GMMs in the network). There will be no reply for commands using the broadcast message. Default address for GMM is address 1, but it is possible to change the address in the service menu of the GMM. Command: The following commands of the specification „MODBUS Application Protocol Specification V1.1“ are supported: Code Command 0x03 Read Holding Register 0x04 Read Input Register 0x06 Write Single Register Data: The length of databytes depends on the transmitted command. (see chapter databytes) CRC L / CRC H The CRC is generated over the full message. The polynom used for the CRC generation is 1 + x2 + x15 + x16 ( XOR - Calculation with 0xA001 (hexadecimal) ). Start value is 0xFFFF. The low byte of the CRC is sent first, followed by the high byte. For further information about the crc generation see „MODBUS over Serial Line Specification & Implementation guide V1.0“.

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1.2.1 Answer of the GMM The GMM only answers, if - it is addressed by the correct address - the length of the data bytes is correct - the CRC is correct Synchronization: After the end of the command, the GMM will wait at least the time length of 3.5 bytes. The pause depends on the command, the timeout is 100ms. Address: The address in the command of the master will be repeated. Command: If it is possible to process the command, the command code will be repeated. If it is not possible to process the command, the GMM will answer with an exception. This is, for example, the byte 0x83 for the command „Read Holding Register (0x03)“. Data: The length of the data bytes and its function depends on the transmitted command. See chapter data bytes. CRC L / CRC H The checksum CRC will be generated over the full message. The checksum will be generated in the same way as described above.

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1.3 Data Bytes

1.3.1 Read Holding Register Command: 0x03 With this command it is possible to read the content of a holding register. Holding registers are parameters with read/write access. Command from Master: 4 data bytes will be transmitted: - Holding register MSB - Holding register LSB - 0x00 - 0x01 (amount of registers, at the moment it is only possible to read single registers) The holding registers will be explained later. Answer of the GMM: Following data bytes will be transmitted: - Holding register MSB - Holding register LSB - Data 1. Holding Register MSB - Data 1. Holding Register LSB Exception Codes: In case of a data processing error the answer will be an exception. 0x02: The allowed address range of the Holding Registers 0xD000 – 0xD0XX (hexadecimal) was exceeded 0x04: A holding register could not be read, because a hardware error occurred

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1.3.2 Read Input Register Command: 0x04 With this command it is possible to read the content of an input register. Input registers are parameters with read-only access. Command from Master: 4 data bytes will be transmitted: - Input register MSB - Input register LSB - 0x00 - 0x01 The input registers will be explained later. Answer of the GMM: 3 data bytes will be transmitted: • 0x02 (number of data bytes) • Data input register MSB • Data input register LSB Exception Codes: In case of an error only one data byte will be transmitted: Exception Codes: 0x02: The allowed address range of the Holding Registers 0xD000 – 0xDXXX (hexadecimal) was exceeded 0x05: An invalid register was accessed (e.g. Motor 7 in a 4 motor system)

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1.3.3 Write Single Register Command: 0x06 With this command it is possible to write data to a holding register. Command from Master: 4 data bytes will be transmitted: - Holding register address MSB - Holding register address LSB - data byte to write MSB - data byte to write LSB The holding registers will be explained later. Answer from the GMM: 4 data bytes will be transmitted: - Holding register address MSB - Holding register address LSB - data byte to write MSB - data byte to write LSB Exception Codes: In case of an error only one data byte will be transmitted: Exception Codes: 0x02: The allowed address range of the Holding Register 0xD000 – 0xDXXX (hexadecimal) was exceeded 0x04: The Holding Register cannot be written because a hardware error occurred

1.3.4 Read Multiple Register Command: 0x04 With this command it is possible to read some registers as an array . Caution: This command does not correspond to the Modbus specification. It is only possible to read 16 and in one case 17 registers at once. No other number of registers is possible. Following registers can be read as an array: (hexadecimal) D100 – D10E (16 registers) (hexadecimal) D111 – D120 (16 registers) (hexadecimal) D131 – D140 (16 registers) (hexadecimal) D151 – D160 (16 registers) (hexadecimal) D170 – D180 (17 registers) (hexadecimal) D181 – D190 (16 registers)

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2 Register

2.1 Overview Following list gives an overview of all possible parameters. They will be explained in the following chapters. Modbus-Address Function Holding Register (hexadecimal)

D000h Control Value D001h Operating Mode D002h Control Parameter Kp1 D003h Control Parameter Ti1 D004h Control Parameter Td1 D005h Control Parameter Kp2 (not yet implemented) D006h Control Parameter Ti2 (not yet implemented) D007h Control Parameter Td2 (not yet implemented) D008h Switching Control System (not yet implemented) D009h Setpoint 1 D00Ah Setpoint 2 D00Bh Watchdog D00Ch Used Refrigerant D00Dh Modbus adress Input Register

D100h Number of Motors of the GMM EC D101h State of the digital inputs of the GMM D102h Function current input AI1 (4 .. 20 mA) D103h Raw Value AI1 D104h AI1 Scaled Value (depending on the selected refrigerant) D105h Function current input AI2 (4..20mA) D106h Raw Value AI2 D107h AI2 Scaled Value (depending on the selected refrigerant) D108h Function Resistor Input AI3 (GTF210) / Raw Value D109h AI3 Scaled Value (depending on the chosen function) D10Ah Function Voltage Input (0..10V) D10Bh Raw Value AI4 D10Ch AI4 Scaled Value (depending on the chosen function) D10Dh Status Manual Mode D10Eh Control Value Manual Mode D10Fh Type of Motorcontrol D110h..D120h Current Energy Consumption of one Motor or in total D131h..D140h Motor temperature (only for GMM EC) D151h..D160h Current Fanspeed (in rpm) D170h..D180h Errors / Alarms of the GMM EC D181h..D190h Current Fanspeed as percentage of the Maximum Speed D200h Current Air Volume as percentage of the Maximum Air Volume

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2.2 Holding Register

2.2.1 Control Value Address: D000h (hexadecimal) With this parameter the control value can be set. The control value is the speed of the fans in the range from 0 – 100%. This parameter will only be processed, if the operating mode 4 is used (see 3.2.2 operating mode). Example: a control value of 10% will be programmed. Command: 01h 06h D0h 00h 00h 0Ah B0h E1h (hexadecimal) Answer: 01h 06h D0h 00h 00h 0Ah B0h E1h (hexadecimal)

Byte Function Value (Hex) 1 Address 01h 2 Write Single

Register 06h

3 Highbyte Register D0h 4 Lowbyte Register 00h 5 Highbyte value 00h 6 Lowbyte value 0Ah 7 Lowbyte CRC B0h 8 Highbyte CRC E1h

2.2.2 Operating Mode Address: D001h (hexadecimal) With this parameter the operating mode of the GMM will be programmed. Following operating modes may be used, which can be set in the service menu. It is also possible to set the operating mode by using the external bus. Caution: The manual mode overrides the operating mode.

2.2.2.1 Automatic internal In this mode the GMM regulates automatically to the setpoint configured in the menu.

2.2.2.2 Automatic external analog In this mode the GMM regulates automatically to the setpoint defined by the external analog input. The analog input which will be used as the setpoint input is set in the I/O configuration.

2.2.2.3 Automatic external bus It is possible to set some parameters over the external bus, e.g. the setpoint to which the control will regulate. The external setpoint will be written in the same register, which can also be altered (in other operating modes) in the menu “setpoints”.

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If there are any communicaction problems, the GMM will use the last transmitted setpoint.

2.2.2.4 Slave external analog The controller converts the external analog signal 1:1 into a control value. The analog input which will be used as the control value is set in the I/O configuration.

2.2.2.5 Slave external bus In this mode the internal control is deactivated. All parameters can be changed, but only the external control value will be used for setting the motor speed. If the external communication is interrupted, the control will use the programmed setpoint (only if the watchdog is activated). Following operating modes are available:

Value Operating Mode 0 Automatic Internal

1 Automatic External analog

2 Automatic External BUS

3 Slave External analog

4 Slave External BUS

Example: The control is using operating mode 2 (Automatic External BUS) Command: 01h 06h D0h 01h 00h 02h 61h 0Bh (hexadecimal) Answer: 01h 06h D0h 01h 00h 02h 61h 0Bh (hexadecimal)

Byte Function Value (Hex)

1 Address 01h 2 Write Single Register 06h 3 Highbyte Register D0h 4 Lowbyte Register 01h 5 Highbyte Value 00h 6 Lowbyte Value 02h 7 Lowbyte CRC 61h 8 Highbyte CRC 0Bh

2.2.3 Control Parameter Kp1 Address: D002h (hexadecimal) With this register the control parameter Kp1 is programmed which is used by the PID controller (for normal and emergency operation, see watchdog). If the external communication is interrupted, the control will use this value. The value has to be multiplied by 10 for precision purposes. The default depends on the type of the heat exchanger. The value range is 0.1 .. 100.0 Example: The control parameter Kp1 will be set to 12.3 .

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Command: 01h 06h D0h 02h 00h 7Bh 50h E9h (hexadecimal) Answer: 01h 06h D0h 02h 00h 7Bh 50h E9h (hexadecimal)

Byte Function Value (Hex)

1 Address 01h 2 Write Single Register 06h 3 Highbyte Register D0h 4 Lowbyte Register 02h 5 Highbyte Value 00h 6 Lowbyte Value 7Bh 7 Lowbyte CRC 50h 8 Highbyte CRC E9h

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2.2.4 Control Parameter Ti1 Address: D003h (hexadecimal) With this register the control parameter Ti1 is programmed which is used by the PID controller (for normal and emergency operation, see watchdog). If the external communication is interrupted, the control will use this value. Setting the value to Ti1 = 0 will deactivate the “I” component. The default depends on the type of the heat exchanger. The value range is 0 .. 1000 Example: The control parameter will be set to 5. Command: 01h 06h D0h 03h 00h 05h 81h 09h Answer: 01h 06h D0h 03h 00h 05h 81h 09h

Byte Function Value (Hex)

1 Address 01h 2 Write Single Register 06h 3 Highbyte Register D0h 4 Lowbyte Register 03h 5 Highbyte Value 00h 6 Lowbyte Value 05h 7 Lowbyte CRC 81h 8 Highbyte CRC 09h

2.2.5 Control Parameter Td1 Address: D004h (hexadecimal) With this register the control parameter Td1 is programmed which is used by the PID controller (for normal and emergency operation, see watchdog). If the external communication interrupts, the control will use this value. Setting the value to Ti1 = 0 will deactivate the “D” component. The default depends on the type of the heat exchanger. The value range is 0 .. 1000 Example: The control parameter will be set to 5. Command: 01h 06h D0h 04h 00h 05h 30h C8h (hexadecimal) Answer: 01h 06h D0h 04h 00h 05h 30h C8h (hexadecimal)

Byte Function Value (Hex)

1 Address 01h 2 Write Single Register 06h 3 Highbyte Register D0h 4 Lowbyte Register 04h 5 Highbyte Value 00h 6 Lowbyte Value 05h 7 Lowbyte CRC 30h 8 Highbyte CRC C8h

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2.2.6 Control Parameter Kp2 (not yet implemented) Address: D005h (hexadecimal)

2.2.7 Control Parameter Ti2 (not yet implemented) Address: D006h (hexadecimal)

2.2.8 Control Parameter Td2 (not yet implemented) Address: D007h (hexadecimal)

2.2.9 Switching Control System (not yet implemented) Address: D008h (hexadecimal)

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2.2.10 Setpoint 1 Address: D009h (hexadecimal) With this register the setpoint 1 will be programmed, which is used for the internal regulation of the GMM. The interpretation of this value can be set in the service menu (pressure or temperature). Following data ranges are permitted: Pressure : 1.0 .. 50.0 bar (only if the used refrigerant is set to „bar“) Temperature : 0.0 .. 100.0°C The value has to be multiplied by 10 for precision purposes. Example: A setpoint of 22.4 °C has to be programmed (if refrigerant is set to „bar“, it is interpreted as 22.4 bar) Command: 01h 06h D0h 09h 00h E0h 60h 80h (hexadecimal) Answer: 01h 06h D0h 09h 00h E0h 60h 80h (hexadecimal)

Byte Function Value (Hex)

1 Address 01h 2 Write Single Register 06h 3 Highbyte Register D0h 4 Lowbyte Register 09h 5 Highbyte Value 00h 6 Lowbyte Value E0h 7 Lowbyte CRC 60h 8 Highbyte CRC 80h

2.2.11 Setpoint 2 Address: D00Ah (hexadecimal) With this register the setpoint 2 will be programmed, which is used for the internal control of the GMM. The interpretation of this value can be set in the service menu (pressure or temperature). Following data ranges are allowed: Pressure : 1,0 .. 50,0 bar (if refrigerant is „bar“) Temperature : 0,0 .. 100,0°C The value has to be multiplied by 10 for precision purposes. Example: A setpoint of 22.4 °C has to be programmed (if refrigerant is „bar“ it is interpreted as 22.4 bar) Befehl: 01h 06h D0h 0Ah 00h E0h 90h 80h (hexadecimal) Antwort: 01h 06h D0h 0Ah 00h E0h 90h 80h (hexadecimal)

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Byte Function Value (Hex)

1 Address 01h 2 Write Single Register 06h 3 Highbyte Register D0h 4 Lowbyte Register 0Ah 5 Highbyte Value 00h 6 Lowbyte Value E0h 7 Lowbyte CRC 90h 8 Highbyte CRC 80h

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2.2.12 Watchdog Address: D00Bh (hexadecimal) Value range 0..250s With this parameter it is possible to program the watchdog time. If the modbus communication is interrupted, the internal PID controller will take over control. The time will be counted in seconds after the reception of the last modbus message. The value 0 deactivates the watchdog. Example: The watchdog time has to be set to 10s. Command: 01h 06h D0h 0Bh 00h 0Ah 40h CFh (hexadecimal) Answer: 01h 06h D0h 0Bh 00h 0Ah 40h CFh (hexadecimal)

Byte Function Value (Hex)

1 Address 01h 2 Write Single Register 06h 3 Highbyte Register D0h 4 Lowbyte Register 0Bh 5 Highbyte Value 00h 6 Lowbyte Value 0Ah 7 Lowbyte CRC 40h 8 Highbyte CRC CFh

2.2.13 Used Refrigerant Address: D00Ch (hexadecimal) This parameter sets the refrigerant which is used in the heat exchanger. The characterisitic curve of the used refrigerant is saved in the GMM. Consequently it is possible to convert pressure <-> temperature. The charateristic curves of the following refrigerants can be selected in the GMM: Value Refrigerant 0 bar 1 R134a 2 R290 3 R404A 4 R407C 5 R410A 6 R507 7 R717 (NH3) 8 R723 9 R744 (CO2) 10 R22 Example: The refrigerant R507 is used for the conversion:

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Command: 01h 06h D0h 0Ch 00h 06h F1h 0Bh (hexadecimal) Answer: 01h 06h D0h 0Ch 00h 06h F1h 0Bh (hexadecimal)

Byte Function Value (Hex) 1 Address 01h 2 Write Single Register 06h 3 Highbyte Register D0h 4 Lowbyte Register 0Ch 5 Highbyte Value 00h 6 Lowbyte Value 06h 7 Lowbyte CRC F1h 8 Highbyte CRC 0Bh

2.2.14 Modbus Address Address: D00Dh (hexadecimal) This parameter sets the modbus address the GMM is using. Note: After setting the new address it is necessary to reset the GMM (Power OFF/ON). Example: The modbus address wil be set to 2. Command: 01h 06h D0h 0Dh 00h 02h A1h 08h (hexadecimal) Answer: 01h 06h D0h 0Dh 00h 02h A1h 08h (hexadecimal) Byte Function Value

(Hex) 1 Address 01h 2 Write Single Register 06h 3 Highbyte Register D0h 4 Lowbyte Register 0Dh 5 Highbyte Value 00h 6 Lowbyte Value 02h 7 Lowbyte CRC A1h 8 Highbyte CRC 08h

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2.3 Input Registers With the command: 01h 04h D1h 00h 00h 10h C8h FAh (hexadecimal) it is possible to read the registers D100 .. D10F (hexadecimal) as an array. The message length of the answer is 37 bytes.

2.3.1 Number of Motors of the GMM EC Address: D100h (hexadecimal) This register contains the number of fans used in the GMM. Example: Command: 01h 04h D1h 00h 00h 01h 71h 36h (hexadecimal) Answer: 01h 04h 02h 00h 08h B8h F6h (hexadecimal)

Byte Function Value (Hex)

1 Address 01h 2 Read Single Register 04h 3 Highbyte Register D1h 4 Lowbyte Register 00h 5 Highbyte Value 00h 6 Lowbyte Value 01h 7 Lowbyte CRC 71h 8 Highbyte CRC 36h

Byte Function Value (Hex)

1 Address 01h 2 Read Single Register 04h 3 Byte Count 02h 4 Highbyte Value 00h 5 Lowbyte Value 08h 6 Lowbyte CRC B8h 7 Highbyte CRC F6h

The GMM uses 8 fans.

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2.3.2 State of the digital inputs of the GMM Address: D101h (hexadecimal) This register contains the state (low or high) of the three digital inputs of the GMM.

Data Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 High byte

X X X X X X X X

Low byte X X X X X DI3 DI2 DI1 X : not defined DI1..DI3 : the three digital inputs of the GMM Command: 01h 04h D1h 01h 00h 01h 59h 36h (hexadecimal) Answer: 01h 04h 02h 00h 06h 39h 32h (hexadecimal) DI1 = connected, DI2 = not connected und DI3 = not connected.

Byte Function Value (Hex)

1 Address 01h 2 Read Single Register 04h 3 Highbyte Register D1h 4 Lowbyte Register 01h 5 Highbyte Value 00h 6 Lowbyte Value 01h 7 Lowbyte CRC 59h 8 Highbyte CRC 36h

Byte Function Value (Hex)

1 Address 01h 2 Read Single Register 04h 3 Byte Count 02h 4 Highbyte Value 00h 5 Lowbyte Value 06h 6 Lowbyte CRC 39h 7 Highbyte CRC 32h

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2.3.3 Function current input AI1 (4 .. 20 mA) Address: D102h (hexadecimal) This register contains the value which represents the function of the current input AI1. This function can be set in the service menu. Value Function

0 No function 1 Actual value 2 Control value slave 3 Setpoint 1 4 Setpoint 2

Command: 01h 04h D1h 02h 00h 01h A9h 36h (hexadecimal) Answer: 01h 04h 02h 00h 02h 38h F1h (hexadecimal) In this example the current input has the function „control value slave“.

Byte Function Value (Hex)

1 Address 01h 2 Read Single Register 04h 3 Highbyte Register D1h 4 Lowbyte Register 02h 5 Highbyte Value 00h 6 Lowbyte Value 01h 7 Lowbyte CRC A9h 8 Highbyte CRC 36h

Byte Function Value (Hex)

1 Address 01h 2 Read Single Register 04h 3 Byte Count 02h 4 Highbyte Value 00h 5 Lowbyte Value 01h 6 Lowbyte CRC 38h 7 Highbyte CRC F1h

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2.3.4 Raw Value AI1 Address: D103h (hexadecimal) This register contains the raw value of the analog input AI1 of the GMM. The analog input has a value range of 0..25mA. The value is multiplied by 10 for precision purposes. Example: Command: 01h 04h D1h 03h 00h 01h F8h F6h (hexadecimal) Answer: 01h 04h 02h 00h 85h 78h 93h (hexadecimal) In this example the input current at AI1 is 13.3mA.

Byte Function Value (Hex)

1 Address 01h 2 Read Single Register 04h 3 Highbyte Register D1h 4 Lowbyte Register 03h 5 Highbyte Value 00h 6 Lowbyte Value 01h 7 Lowbyte CRC F8h 8 Highbyte CRC F6h

Byte Function Value (Hex)

1 Address 01h 2 Read Single Register 04h 3 Byte Count 02h 4 Highbyte Value 00h 5 Lowbyte Value 85h 6 Lowbyte CRC 78h 7 Highbyte CRC 93h

2.3.5 AI1 Scaled Value (depending on the selected refrigerant) Address: D104h (hexadecimal) This register contains the value of the analog input AI1. The interpretation of this value is controlled by the settings in the service menu. The value range is as follows: Pressure : 1.0 .. 50.0 bar (only if the used refrigerant is set to „bar“) Temperature : -50.0 .. 100.0°C The value is multiplied by 10 for precision purposes. If the value is negative the highest bit of the MSB is set. In this case the value has to be calculated in the following way: Read Value : $FE4C

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Value = $10000 - $FE4C = $1B4 -> 436 / 10 = - 43.6 °C Example: Command: 01h 04h D1h 04h 00h 01h 49h 37h (hexadecimal) Answer: 01h 04h 02h 01h 85h 79h 03h (hexadecimal)

Byte Function Value (Hex) 1 Address 01h 2 Read Single Register 04h 3 Highbyte Register D1h 4 Lowbyte Register 04h 5 Highbyte Value 00h 6 Lowbyte Value 01h 7 Lowbyte CRC 49h 8 Highbyte CRC 37h

Byte Function Value (Hex) 1 Address 01h 2 Read Single Register 04h 3 Byte Count 02h 4 Highbyte Value 01h 5 Lowbyte Value 85h 6 Lowbyte CRC 79h 7 Highbyte CRC 03h

In this example the temperature is 38.9°C.

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2.3.6 Function current input AI2 (4..20mA) Address: D105h (hexadecimal) This register contains the value which represents the function of the current input AI2. This function can be set in the service menu. Value Function

0 No function 1 Actual value 2 Control value slave 3 Setpoint 1 4 Setpoint 2 5 Outdoor

temperature Befehl: 01h 04h D1h 05h 00h 01h 92h B1h (hexadecimal) Antwort: 01h 04h 02h 00h 02h 38h F1h (hexadecimal) In this example the current input has the function „control value slave“.

Byte Function Value (Hex)

1 Address 01h 2 Read Single Register 04h 3 Highbyte Register D1h 4 Lowbyte Register 05h 5 Highbyte Value 00h 6 Lowbyte Value 01h 7 Lowbyte CRC 92h 8 Highbyte CRC B1h

Byte Function Value (Hex)

1 Address 01h 2 Read Single Register 04h 3 Byte Count 02h 4 Highbyte Value 00h 5 Lowbyte Value 02h 6 Lowbyte CRC 38h 7 Highbyte CRC F1h

2.3.7 Raw Value AI2 Address: D106h (hexadecimal) This register contains the raw value of the analog input AI2 of the GMM. The analog input has a value range of 0..25mA. The value is multiplied by 10 for precision purposes.

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Example: Command: 01h 04h D1h 06h 00h 01h E8h F7h (hexadecimal) Answer: 01h 04h 02h 00h 85h 78h 93h (hexadecimal) In this example the input current at AI2 is 13.3mA.

Byte Function Value (Hex)

1 Address 01h 2 Read Single Register 04h 3 Highbyte Register D1h 4 Lowbyte Register 06h 5 Highbyte Value 00h 6 Lowbyte Value 01h 7 Lowbyte CRC 92h 8 Highbyte CRC B1h

Byte Function Value (Hex)

1 Address 01h 2 Read Single Register 04h 3 Byte Count 02h 4 Highbyte Value 00h 5 Lowbyte Value 01h 6 Lowbyte CRC 78h 7 Highbyte CRC 93h

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2.3.8 AI2 Scaled Value (depending on the selected refrigerant) Address: D107h (hexadecimal) This register contains the scaled value of the analog input AI2. The interpretation of this value is controlled by the settings in the service menu. The value range is as follows: Pressure : 1.0 .. 50.0 bar (only if the used refrigerant is set to „bar“) Temperature : -50.0 .. 100.0°C The value is multiplied by 10 for precision purposes. If the value is negative the highest bit of the MSB is set. In this case the value has to be calculated in the following way: Read Value : $FE4C Value = $10000 - $FE4C = $1B4 -> 436 / 10 = - 43.6 °C Example: Befehl: 01h 04h D1h 07h 00h 01h B9h 37h (hexadecimal) Antwort: 01h 04h 02h 01h 85h 79h 03h (hexadecimal)

Byte Function Value (Hex)

1 Address 01h 2 Read Single Register 04h 3 Highbyte Register D1h 4 Lowbyte Register 07h 5 Highbyte Value 00h 6 Lowbyte Value 01h 7 Lowbyte CRC B9h 8 Highbyte CRC 37h

Byte Function Value (Hex)

1 Address 01h 2 Read Single Register 04h 3 Byte Count 02h 4 Highbyte Value 01h 5 Lowbyte Value 85h 6 Lowbyte CRC 79h 7 Highbyte CRC 03h

In this example the temperature is 38.9°C.

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2.3.9 Function Resistance Input Address: D108h (hexadecimal) This register contains the value which represents the function of the analog input AI3. This function can be changed in the service menu of the GMM. Value Funktion

0 No function 1 Actual value 5 Outdoor

temperature Command: 01h 04h D1h 08h 00h 01h 89h 34h Answer: 01h 04h 02h 00h 01h 78h F0h

Byte Function Value (Hex)

1 Address 01h 2 Read Single Register 04h 3 Highbyte Register D1h 4 Lowbyte Register 08h 5 Highbyte Value 00h 6 Lowbyte Value 01h 7 Lowbyte CRC 89h 8 Highbyte CRC 34h

Byte Function Value (Hex)

1 Address 01h 2 Read Single Register 04h 3 Byte Count 02h 4 Highbyte Value 00h 5 Lowbyte Value 01h 6 Lowbyte CRC 78h 7 Highbyte CRC F0h

2.3.10 Resistor Input / Raw Value (not yet implemented)

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2.3.11 Scaled Value AI3 (GTF210) Address : D109h (hexadecimal) This register contains the scaled value (using the temperature sensor GTF210) of the analog input AI3. The interpretation of this value is controlled by the settings in the service menu (Celsius or Fahrenheit). The value is multiplied by 10 for precision purposes. If the value is negative the highest bit of the MSB is set. In this case the value has to be calculated in the following way: Example: Read Value : $FE4C Value = $10000 - $FE4C = $1B4 -> 436 / 10 = - 43.6 °C Example: Command: 01h 04h D1h 09h 00h 01h D8h F4h (hexadecimal) Answer: 01h 04h 02h 01h 2Dh 78h BDh (hexadecimal)

Byte Function Value (Hex)

1 Address 01h 2 Read Single Register 04h 3 Highbyte Register D1h 4 Lowbyte Register 09h 5 Highbyte Value 00h 6 Lowbyte Value 01h 7 Lowbyte CRC D8h 8 Highbyte CRC F4h

Byte Function Value (Hex)

1 Address 01h 2 Read Single Register 04h 3 Byte Count 02h 4 Highbyte Value 01h 5 Lowbyte Value 2Dh 6 Lowbyte CRC 78h 7 Highbyte CRC BDh

In this example the temperature is 30.1°C.

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2.3.12 Function Voltage Input (0..10V) Address : D10Ah (hexadecimal) This register contains the value which represents the function of the analog input AI3. This function can be changed in the service menu of the GMM. Value Function

0 No function 1 Actual value 2 Control Value slave 3 Setpoint 1 4 Setpoint 2

Command: 01h 04h D1h 0Ah 00h 01h 28h F4h Answer: 01h 04h 02h 00h 02h 38h F1h In this example the function of the voltage input AI4 is „control value slave“.

Byte Function Value (Hex)

1 Address 01h 2 Read Single Register 04h 3 Highbyte Register D1h 4 Lowbyte Register 0Ah 5 Highbyte Value 00h 6 Lowbyte Value 01h 7 Lowbyte CRC 28h 8 Highbyte CRC F4h

Byte Function Value (Hex)

1 Address 01h 2 Read Single Register 04h 3 Byte Count 02h 4 Highbyte Value 00h 5 Lowbyte Value 02h 6 Lowbyte CRC 38h 7 Highbyte CRC F1h

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2.3.13 Voltage Input AI4 (0..10V) / Raw Value Address : D10Bh (hexadecimal) This register contains the raw value of the analog input AI4 of the GMM. The value range of the analog input is 0..10V. The value is multiplied by 10 for precision purposes. Example: Command: 01h 04h D1h 0Bh 00h 01h 79h 34h (hexadecimal) Answer: 01h 04h 02h 00h 57h F8h CEh (hexadecimal)

Byte Function Value (Hex)

1 Address 01h 2 Read Single Register 04h 3 Highbyte Register D1h 4 Lowbyte Register 0Bh 5 Highbyte Value 00h 6 Lowbyte Value 01h 7 Lowbyte CRC 79h 8 Highbyte CRC 34h

Byte Function Value (Hex)

1 Address 01h 2 Read Single Register 04h 3 Byte Count 02h 4 Highbyte Value 00h 5 Lowbyte Value 57h 6 Lowbyte CRC F8h 7 Highbyte CRC CEh

In this example the input voltage at AI4 is 8.7V

2.3.14 Voltage Input AI4, Scaled Value Address: D10Ch (hexadecimal) Not yet implemented.

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2.3.15 Status Manual Mode Address : D10Dh (hexadecimal) This register contains the status info of the manual mode. Value Funktion

0 Manual mode activated 1 Manual mode deactivated

Command: 01h 04h D1h 0Dh 00h 01h 99h 35h (hexadecimal) Answer: 01h 04h 02h 00h 00h B9h 30h (hexadecimal) In this example the manual mode is deactivated.

Byte Function Value (Hex)

1 Address 01h 2 Read Single Register 04h 3 Highbyte Register D1h 4 Lowbyte Register 0Dh 5 Highbyte Value 00h 6 Lowbyte Value 01h 7 Lowbyte CRC 99h 8 Highbyte CRC 35h

Byte Function Value (Hex)

1 Address 01h 2 Read Single Register 04h 3 Byte Count 02h 4 Highbyte Value 00h 5 Lowbyte Value 00h 6 Lowbyte CRC B9h 7 Highbyte CRC 30h

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2.3.16 Control Value Manual Mode Address : D10Eh (hexadecimal) This register contains the manual mode control value (in %). Command: 01h 04h D1h 0Eh 00h 01h 69h 35h (hexadecimal) Answer: 01h 04h 02h 00h 3Ch 38h F1h (hexadecimal) In this example the manual mode control value is set to 60%.

Byte Function Value (Hex)

1 Address 01h 2 Read Single Register 04h 3 Highbyte Register D1h 4 Lowbyte Register 0Eh 5 Highbyte Value 00h 6 Lowbyte Value 01h 7 Lowbyte CRC 69h 8 Highbyte CRC 35h

Byte Function Value (Hex)

1 Address 01h 2 Read Single Register 04h 3 Byte Count 02h 4 Highbyte Value 00h 5 Lowbyte Value 3Ch 6 Lowbyte CRC B9h 7 Highbyte CRC 21h

2.3.17 Type of Motorcontrol (ECC, SinCon, PhaseCut etc.) Address : D10Fh (hexadecimal) This register describes the type of motorcontrol connected to the GRC. Following motorcontrols are possible: 00h = EC-Controller 02h = SinCon 03h = StepControl (future) 04h = PhaseCut (future) FFh = no motorcontrol

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Command: 01h 04h D1h 0Fh 00h 01h 69h 35h (hexadecimal) Answer: 01h 04h 02h 00h 02h 38h F1h (hexadecimal)

Byte Function Value (Hex)

1 Address 01h 2 Read Single Register 04h 3 Highbyte Register D1h 4 Lowbyte Register 0Eh 5 Highbyte Value 00h 6 Lowbyte Value 01h 7 Lowbyte CRC 38h 8 Highbyte CRC F5h

Byte Function Value (Hex)

1 Address 01h 2 Read Single Register 04h 3 Byte Count 02h 4 Highbyte Value 00h 5 Lowbyte Value 02h 6 Lowbyte CRC 38h 7 Highbyte CRC F1h

In this example a frquency converter is connected to the GRC.

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2.3.18 Current Energy Consumption of one Motor or in total Address: D110h..D120h (hexadecimal) These registers contain the current energy consumption of the fans. D110h : Total energy consumption [W] D111h..D120h : Single energy consumption [W], with D111 = Fan 1 .. D120 = Fan 16 The register range depends on the number of connected fans. Example: The current energy consumption of fan 9 will be read. Command: 01h 04h D1h 19h 00h 01h A0h F1h (hexadecimal) Answer: 01h 04h 02h 08h 5Ch BEh C9h (hexadecimal)

Byte Function Value (Hex)

1 Address 01h 2 Read Single Register 04h 3 Highbyte Register D1h 4 Lowbyte Register 19h 5 Highbyte Value 00h 6 Lowbyte Value 01h 7 Lowbyte CRC A0h 8 Highbyte CRC F1h

Byte Function Value (Hex)

1 Address 01h 2 Read Single Register 04h 3 Byte Count 02h 4 Highbyte Value 08h 5 Lowbyte Value 5Ch 6 Lowbyte CRC BEh 7 Highbyte CRC C9h

In this example the energy consumption of fan 9 is 214W Read data as an array: With the command: 01h 04h D1h 11h 00h 10h 98h FFh (hexadecimal) it is possible to read the registers D111..D120 (hexadecimal) as an array. The data length of the answer is 37 bytes.

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2.3.19 Motor temperature (only for GMM EC) Address: D131h..D140h (hexadecimal) These registers contain the temperatures of the fans (motor temperature and the temperature of the electronic circuits) D131h..D140h : D131h = Fan 1 .. D140h = Fan 16 2 Bytes will be returned: Byte1 : Motor temperature (used unit: °C) Byte2 : Temperature of the electronic circuits of the fan (used unit °C) Example: In this example the temperature of fan 9 will be read. Command: 01h 04h D1h 39h 00h 01h D8h FBh (hexadecimal) Answer: 01h 04h 02h 34h 21h 6Fh E8h (hexadecimal)

Byte Function Value (Hex)

1 Address 01h 2 Read Single Register 04h 3 Highbyte Register D1h 4 Lowbyte Register 39h 5 Highbyte Value 00h 6 Lowbyte Value 01h 7 Lowbyte CRC D8h 8 Highbyte CRC FBh

Byte Function Value (Hex)

1 Address 01h 2 Read Single Register 04h 3 Byte Count 02h 4 Highbyte Value 34h 5 Lowbyte Value 21h 6 Lowbyte CRC 6Fh 7 Highbyte CRC E8h

In this example the motor temperature of fan 9 is 52°C and the temperature of the electronic circuits is 33°C. Read as an array: With the command: 01h 04h D1h 31h 00h 10h 99h 35h it is possible to read the registers D131..D140 as an array. The data length of the answer is 37 bytes.

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2.3.20 Current Fan Speed (in rpm) Address: D151h .. D160h (hexadecimal) These registers contain the current fan speed of the connected fans (in rpm). D151h = Fan 1 .. D160h = Fan 16 The register range depends on the number of connected fans. Example: Command: 01h 04h D1h 56h 00h 01h E8h E6h (hexadecimal) Answer: 01h 04h 02h 01h C5h 78h F3h (hexadecimal)

Byte Function Value (Hex)

1 Address 01h 2 Read Single Register 04h 3 Highbyte Register D1h 4 Lowbyte Register 56h 5 Highbyte Value 00h 6 Lowbyte Value 01h 7 Lowbyte CRC E8h 8 Highbyte CRC E6h

Byte Function Value (Hex)

1 Address 01h 2 Read Single Register 04h 3 Byte Count 02h 4 Highbyte Value 01h 5 Lowbyte Value C5h 6 Lowbyte CRC 78h 7 Highbyte CRC F3h

In this example the current fan speed of fan 1 is 453 rpm Read as an array: With the command: 01h 04h D1h 51h 00h 10h 99h 2Bh (hexadecimal) it is possible to read the registers D151..D160 (hexadecimal) as an array. The data length of the answer is 37 bytes.

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2.3.21 Errors / Alarms of the GMM Address : D170h (hexadecimal) This register contains information about the condition of the GMM. D170h : System condition GMM System condition GMM: D170h Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0

Highbyte HardwareErr X X X X X X X Lowbyte X X X ErrorAI4 ErrorAI3 ErrorAI2 ErrorAI1 ErrorAI1: Error current input AI1 ErrorAI2: Error current input AI2 ErrorAI3: Error resistor input AI3 ErrorAI4: Error voltage input AI4 HardwareErr: Hardware error, failure of all fans

2.3.22 Errors / Alarms of the GMM EC Address : D171h .. D180h (hexadecimal) These registers contain information about the condition of the fans D171h : Fan 1 … D180h : Fan 16 Fan condition: D171h-D180h

Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0

Highbyte X X X SKF UnderVolt OverVolt Brake IntTemp Lowbyte Hallsensor WrongFan MotBlock CableBrk FanFail PowSup ElecTemp MotorTemp SKF: Communication error between the master and slave controller of the fan UnderVolt: the internal rectified voltage is too low OverVolt: the internal rectified voltage is too high Brake: activated at external drive in reverse direction IntTemp: internal temperature is too high Hallsensor: hallsensor failure WrongFan: wrong fan or the VT-Number does not correspond to the system MotBlock: the fan is blocked CableBrk: the RS485 connection to the fan is interrupted FanFail: is always set together with an error PowSup: power supply failure ElecTemp: electronic circuit temperature is too high MotorTemp: motor temperature is too high Command: 01h 04h D1h 75h 00h 01h 19h 2Ch Answer: 01h 04h 02h 00h 09h 79h 36h

Byte Function Value (Hex)

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1 Address 01h 2 Read Single Register 04h 3 Highbyte Register D1h 4 Lowbyte Register 75h 5 Highbyte Value 00h 6 Lowbyte Value 01h 7 Lowbyte CRC 19h 8 Highbyte CRC 2Ch

Byte Function Value

(Hex) 1 Address 01h 2 Read Single Register 04h 3 Byte Count 02h 4 Highbyte Value 00h 5 Lowbyte Value 09h 6 Lowbyte CRC 79h 7 Highbyte CRC 36h

In this example fan 5 has got motor temperature problem (FanFail + MotorTemp) With the command: 01h 04h D1h 70h 00h 11h 08h E1h (hexadecimal) it is possible to read the registers D170h..D180h (hexadecimal) as an array. The data length of the answer is 39 bytes.

2.3.23 Thermal Output Not yet implemented.

2.3.24 Current Fanspeed as percentage of the Maximum Speed Address: D181h .. D190h (hexadecimal) These registers contain the current fan speed as percentage of the maximum speed. D181h = Fan 1 .. D190h = Fan 16 The register range depends on the number of connected frequency converters. Example: Command: 01h 04h D1h 86h 00h 01h E9h F1h (hexadecimal) Answer: 01h 04h 02h 00h 32h 38h E5h (hexadecimal)

Byte Function Value (Hex)

1 Address 01h 2 Read Single Register 04h 3 Highbyte Register D1h 4 Lowbyte Register 86h 5 Highbyte Value 00h 6 Lowbyte Value 01h 7 Lowbyte CRC E9h

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8 Highbyte CRC F1h

Byte Function Value (Hex)

1 Address 01h 2 Read Single Register 04h 3 Byte Count 02h 4 Highbyte Value 00h 5 Lowbyte Value 32h 6 Lowbyte CRC 38h 7 Highbyte CRC E5h

In this example the current fan speed of fan 6 is 50% of the maximum speed. Read as an array: With the command: 01h 04h D1h 81h 00h 10h 98h D2h (hexadecimal) it is possible to read the registers D181h..D190h (hexadecimal) as an array. The data length of the answer is 37 bytes.

2.3.25 Current Air Volume as percentage of the Maximum Air Volume Address: D200h (hexadecimal) This register contains the current air volume as percentage of the Maximum Air Volume. Example: Command: 01h 04h D2h 00h 00h 01h 08h B2h (hexadecimal) Answer: 01h 04h 02h 00h 32h 38h E5h (hexadecimal)

Byte Function Value (Hex)

1 Address 01h 2 Read Single Register 04h 3 Highbyte Register D1h 4 Lowbyte Register 86h 5 Highbyte Value 00h 6 Lowbyte Value 01h 7 Lowbyte CRC 08h 8 Highbyte CRC B2h

Byte Function Value (Hex)

1 Address 01h 2 Read Single Register 04h 3 Byte Count 02h 4 Highbyte Value 00h 5 Lowbyte Value 32h 6 Lowbyte CRC 38h 7 Highbyte CRC E5h

In this example the current air volume is 50%.