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No. CP-SP-1300E Air Flowmeter User's Manual Communication Functions Thank you for purchasing the MCF Air Flowmeter. This manual contains information for ensuring the correct use of the MCF. It also provides necessary information for installation, maintenance, and trou- bleshooting. This manual should be read by those who design and maintain equipment that uses the MCF.
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If you should find an error or omis- sion, please contact the azbil Group. In no event is Azbil Corporation liable to anyone for any indirect, special or consequential damages as a result of using this product.
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Conventions Used in This Manual ■ To prevent injury to the operator and others, and to prevent property damage, the following types of safety precautions are indicated: Warnings are indicated when mishandling this product might result in WARNING death or serious injury. Cautions are indicated when mishandling this product might result in CAUTION minor injury to the user, or only physical damage to the product.
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Safety Precautions CAUTION Before removing, mounting, or wiring the MCF, be sure to turn off the MCF and all con- nected devices. Failure to do so might cause electric shock. Do not disassemble the MCF. Doing so might cause malfunction. Wire this device properly, according to the standards given in this document, using the specified types of wire and connection procedures.
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A total of three different manuals are available for the MCF. Read them as necessary for your specific requirements. If a manual you require is not available, contact the azbil Group or its dealer. MCF Air Flowmeter User's Manual for Installation Manual No.
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Organization of This User's Manual This manual is organized as follows: Chapter 1. OVERVIEW This chapter describes communication outline of the MCF series. Chapter 2. WIRING This chapter describes RS-485 wiring methods to make a communication link between the MCF series and other instruments. Chapter 3.
Chapter 1. OVERVIEW The MCF series flowmeter (hereafter referred to as the MCF or the slave station) can communicate settings and data with a host device, such as a PC or PLC (also called the master station). Users write a customized communication program for this purpose.
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Chapter 1. OVERVIEW ■ Hardware configuration 2 Master station LAN (Ethernet) MODBUS converter (gateway) RS-485 (3-wire system) Slave station (MCF) Max. 31units...
Chapter 2. WIRING CAUTION Before removing, mounting, or wiring the MCF, be sure to turn off the MCF and all connected devices. Failure to do so might cause electric shock. Do not disassemble the MCF. Doing so might cause malfunction. Wire this device properly, according to the standards given in this document, using the specified types of wire and connection procedures.
• Ground the shield of shielded cable to the frame ground (FG) at one end. Do not ground the shield at both ends. • Azbil Corporation’s CMC10L001A000 controller can be used as a converter for the master station. • Be sure to connect the SG terminals to each other. Failure to do so...
• Ground the shield of shielded cable to the frame ground (FG) at one end. Do not ground the shield at both ends. • Azbil Corporation’s CMC10L001A000 controller can be used as a converter for the master station. • Be sure to connect the SG terminals to each other. Failure to do so...
Chapter 3. SETTING Before starting communication, set the communication condition and station address of the slave station to meet that of the master station. ■ Setting method Before starting RS-485 communications, follow the procedure below to set the MCF’s communication parameters and station address so that they are compatible with the master station.
Chapter 3. SETTING ■ Function settings Func Name Settings Factory Description setting C 30 Station address 01 to 99 There is no communication if the address remains set at “00.” Set an address that is not already being used by another unit. C 31 Transmission 00: No communication speed...
Chapter 4. COMMUNICATION PROCEDURE 4 - 1 Outline of Communication Procedure and Messages This chapter describes the outline of communication procedure and the concept behind message configuration. ■ Communication procedure The following is a simple breakdown of the communication procedure: (1) The master station transmits an instruction message to a slave station to specify a station for communication.
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Chapter 4. COMMUNICATION PROCEDURE ● RTU (1) Communications frames All messages are written in binary data. RTU communications frame Frame structure Number of bytes Description Start > 3.5 characters Silent interval Address Station address Function Refer to function code descriptions. Data Refer to function code descriptions.
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Chapter 4. COMMUNICATION PROCEDURE /******************************************* Argument 1: Length of character string (number of bytes) Argument 2: Pointer to beginning of character string Function value: Calculation result *******************************************/ UH get_crc16(INT len, UB *p) UH dt_16; UH next; UH carry; INT i; dt_16 = 0xffff;...
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Chapter 4. COMMUNICATION PROCEDURE ● ASCII (1) Communications frame The whole message except for delimiters is written with hexadecimal ASCII codes. The frame differs depending on the communications type. Note: the MCF accepts only capital letters. ASCII commands and responses Frame structure Number of characters Description...
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Chapter 4. COMMUNICATION PROCEDURE ● Abnormal termination codes In keeping with the Modbus protocol, when an error occurs there is a response to the error. The same set of error responses is used for all the function codes. The tables below show the responses to error for RTU and ASCII modes. RTU mode responses to error Frame structure Number of bytes...
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Chapter 4. COMMUNICATION PROCEDURE ● Conditions under which no response message is sent The MCF sends no response messages under the following conditions: • When it receives a message during initialization (the first 8 seconds or so after power-on). • When an LRC or CRC error occurs. •...
Chapter 4. COMMUNICATION PROCEDURE 4 - 2 Command ■ Function 0x03 (Read multiple words command) Function 0x03, Read holding registers, is the command for reading multiple words. (1) RTU mode Commands and responses are shown in the table below. Refer to “RTU mode responses to error” above. RTU mode send command Frame structure Number of bytes...
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Chapter 4. COMMUNICATION PROCEDURE (2) ASCII mode Commands and normal responses are shown below. For abnormal responses refer to “ASCII mode responses to error” above. ASCII mode send command Frame structure Description Number of bytes Start ‘:’ fixed Address Station address (hexadecimal ASCII) Function ‘0’...
Chapter 4. COMMUNICATION PROCEDURE ■ Function 0x06, Write single register (write 1 word command) (1) RTU mode Commands and normal responses are shown below. (Commands and normal responses are the same.) For abnormal responses refer to “RTU mode responses to error” above. RTU mode send command, normal responses Frame structure Number of bytes...
Chapter 4. COMMUNICATION PROCEDURE ■ Function 0x10, Write multiple registers (Write multiple words command) (1) RTU mode Commands and normal responses are shown below. (The same table applies to both.) For abnormal responses refer to “RTU mode responses to error” above. RTU mode commands Frame structure Number of bytes...
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Chapter 4. COMMUNICATION PROCEDURE (2) ASCII mode Commands and normal responses are shown below. For abnormal responses refer to “ASCII mode responses to error” above. ASCII mode commands Frame structure Description Number of bytes Start ‘:’ fixed Address Station address (hexadecimal ASCII) Function ‘1’...
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Chapter 4. COMMUNICATION PROCEDURE Example: 3AH 30H 31H 30H 33H 30H 37H 44H 31H 30H 30H 30H 32H 31H 35H 0DH 0AH (1) Beginning of message. (2) Station address. (3) Function code. (4) Address of first word. (5) Number of words to write. (6) LRC (7) Delimiter. 4-13...
Chapter 4. COMMUNICATION PROCEDURE 4 - 3 Timing Specifications ■Timing specifications for instruction and response messages The following precautions regarding the transmission timing of instruction mes- sages from the master station and response messages from the slave station should be observed: ●...
Chapter 5. COMMUNICATION DATA TABLE 5 - 1 Basic Communication Data Processing ■ Communication data types and formats ● Types of communication data The communications data are categorized as follow: • Device related data • Operating status related data • Instantaneous flow rate related data •...
Chapter 5. COMMUNICATION DATA TABLE ■ Data address The data addresses are allocated as shown in the table below. Communication data Offset value Address Offset value Address decimal number decimal number decimal number decimal number (hex number) (hex number) (hex number) (hex number) Device related data 1000...
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Chapter 5. COMMUNICATION DATA TABLE 5 - 2 Communication Data Table The enabling conditions for the address and R/W (Read/Write) of each data are specified in the following table: The meaning of R/W column marks: ❍ : R/W (Read/Write) possible ✕...
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Chapter 5. COMMUNICATION DATA TABLE Name Settings EEPROM Remarks address address ❍ ✕ Communications 00: MODBUS (RTU) 1007 – – See the settings for type 01: MODBUS (ASCII) “C33.” ❍ ✕ Serial No. of 0 to 65535 1008 – – measuring instrument ❍...
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Chapter 5. COMMUNICATION DATA TABLE ■ Operating status related data Name Settings EEPROM Remarks address R address ❍ ✕ Alarm status 1201 – – ❍ ✕ Event status 0: Event OFF 1202 – – * 1: Event ON ❍ ✕ Undefined (normally 0) 1203...
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Chapter 5. COMMUNICATION DATA TABLE ■ Instantaneous flow rate related data Name Settings EEPROM Remarks address address ❍ ✕ Instantaneous flow 1401 – – rate status ❍ ✕ Instantaneous flow rate 0 to 65535 1402 – – ❍ ✕ 0 to 3 Flow rate units 1403 –...
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Chapter 5. COMMUNICATION DATA TABLE ■ Integrated flow rate related data Name Data range EEPROM Remarks address address ❍ ❍ ❍ ❍ Integrated flow 0 to 65535 1601 4601 Be sure to use 1 command, namely (last digits) * the command for reading continuous words, to read the peak and low values.
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Chapter 5. COMMUNICATION DATA TABLE ■ Function setup related data Name Settings EEPROM Remarks address address ❍ ❍ ❍ ❍ Key lock 00: Unlocked 2001 5001 The available settings are the same as those for “C0 1.” setting 01: Key locked ❍...
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Chapter 5. COMMUNICATION DATA TABLE Name Settings EEPROM Remarks address address ❍ ✕ ✕ ✕ Undefined (normally 0) 2010 to 2029 ❍ ❍ Station address 00 to 99 – – 5030 The settings will become (setting effective effective at the next power-on. on reboot) * 00 is the factory setting.
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Chapter 5. COMMUNICATION DATA TABLE ■ Parameter setup related data Name Settings EEPROM Remarks address address ❍ ❍ ❍ ❍ Event 1 instantaneous Any flow rate within 2201 5201 The available settings are the flow rate 1 a range equivalent same as those for “E1.SP.”...
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Chapter 5. COMMUNICATION DATA TABLE ■ Maintenance mode Name Settings EEPROM Remarks address address ❍ ❍ ❍ ❍ Calculation filter 1 to 32 2801 5801 The available settings are the same as those for “FLt.” ❍ ❍ ❍ ❍ Measurement 5 to 100 2802 5802...
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Chapter 6. TROUBLESHOOTING Check items in case communication is disabled (1) Check the power supply. (2) Check the wiring. (3) Check if the communication conditions for the MCF series meet those for the host computer. If any one of the following setting items is different between both stations, communication is disabled: The underlined items mean that they can be set on the MCF series side.
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Chapter 7. SPECIFICATIONS ■ RS-485 specifications Item Specifications Transmission mode Balanced Transmission line 3-wire system Transmission speed (bps) 4800, 9600, 19200 Transmission distance 500 m max. Communications flow Half duplex Synchronization Start-stop synchronization Data format Data length: 8 data bits (MODBUS RTU), 7 data bits (MODBUS ASCII), Parity: no parity, even parity, odd parity Stop bit: 1 stop bit, 2 stop bits...
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Appendix ■ Code table UPPER LOWER SPACE " & < > The shaded part ( ) is not used for this communication system. (The codes to be used change every instrument.) App-1...
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Revision History Printed Manual Number Edition Revised pages Description date CP-SP-1300E 1st Edition Sep. 2009 2nd Edition Apr. 2011 Terms were standardized ii, 2-1 CAUTION changed. Explanation changed in "Setting method." Function No. C32 changed. Communication conditions changed. "Standard" deleted from operating pressure settings.
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Azbil Corporation's products. 2. Ascertainment of suitability You are required to ascertain the suitability of Azbil Corporation's products in case of your use of the same with your machinery, equipment, etc. (hereinafter referred to as "Equipment") on your own responsibility, taking the following matters into consideration: (1) Regulations and standards or laws that your Equipment is to comply with.
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Although acceleration of the above situation varies depending on the conditions or environment of use of the products, you are required not to use any Azbil Corporation's products for a period exceeding ten (10) years unless otherwise stated in specifications or instruction manuals.
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Specifications are subject to change without notice. (09) 1-12-2 Kawana, Fujisawa Kanagawa 251-8522 Japan URL: http://www.azbil.com 1st edition: Sep. 2009 (M) 3rd edition: Apr. 2012 (M)
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