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RS485 
Bus coupler BC8000 
 

 
 
 
 
 

 
 
 
 
 
 
 
 
 
 

Version: 2.3 
Last change: 2006-11-06

 

 

Summary of Contents for BC8000

Page 1: ...RS485 Bus coupler BC8000 Version 2 3 Last change 2006 11 06 ...

Page 2: ... Controller BC8000 18 System Introduction 18 Interface Programming 19 The Medium Plugs and Cables 22 The User Programming Interface 23 Remanent Data 23 Persistent Data 23 4 Appendix 25 Example Process image in the bus terminal controller 25 Representation of analog signals in the process image 27 Baud Rate Selection Table 28 Read out address 28 Programming Example 29 BC8000 as a Slave 31 General I...

Page 3: ...ecked for consistency with performance data standards or other characteristics None of the statements of this manual represents a guarantee Garantie in the meaning of 443 BGB of the German Civil Code or a statement about the contractually expected fitness for a particular purpose in the meaning of 434 par 1 sentence 1 BGB In the event that it contains technical or editorial errors we retain the ri...

Page 4: ...ted and nullify the liability of Beckhoff Automation GmbH Description of safety symbols The following safety symbols are used in this documentation They are intended to alert the reader to the associated safety instructions Danger This symbol is intended to highlight risks for the life or health of personnel Attention This symbol is intended to highlight risks for equipment materials or the enviro...

Page 5: ...location in the installation Using an industrial PC as control unit makes it possible to implement the operating and monitoring element as part of the control hardware so the control unit can be located on an operating desk control point or similar The bus terminals constitute the decentralized input output level of the control unit in the switch cabinet and its subordinate terminal cabinets As we...

Page 6: ...of the bus terminal 02 01 PE PE WD RX TX PLC RS 485 BECKHOFF 24V 0V 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 K bus End terminal Galvanic isolation Potential feed terminal Power contacts RS485 bus controller BC 8000 Supply voltage for the bus controller Additional characteristics of the bus terminal controllers Bus terminal controllers BC differ from bus couplers BK in that in addition to K bus proc...

Page 7: ... input maximum 24 V maximum 10 A The six lower connections with spring terminals can be used to supply power to the peripherals The spring terminals are connected in pairs to the power contacts The power supply to the power contacts has no connection to the power supply of the bus couplers The power input is designed to permit voltages up to 24 V The pair wise arrangement and the electrical connec...

Page 8: ...Basic information 8 BC8000 ...

Page 9: ...exchange of data between the bus coupler and the bus terminals Part of the data exchange takes place via a ring structure within the K bus Disengaging the K bus for example by pulling on one the bus terminals will break this circuit so that data can no longer be exchanged However there are mechanisms in place which enable the bus coupler to locate the interruption and report it Supply isolation 3 ...

Page 10: ...l test and read in the configuration from which it constructs an internal structure list which is not accessible from outside If an error occurs the bus coupler will enter the operating mode STOP If the start up sequence is completed without errors the bus coupler will enter the mode fieldbus start Start up behaviour of the bus coupler The bus coupler reports the error to the master by means of th...

Page 11: ...can remove them without effort if you first release the latching mechanism by pulling the orange tab You should carry out work on the bus terminals and the bus coupler only while they are switched off if you plug or unplug components while the power is on you may briefly provoke some undefined state and for instance reset the bus coupler You can attach up to 64 bus terminals in series on the right...

Page 12: ...ginning of a new track The bus coupler can also be used to supply power to the power contacts The power contact labeled PE can be used as protective earth or ground This contact stands proud for safety reasons and can carry short circuit currents of up to 125A Note that in the interests of electromagnetic compatibility the PE contacts are capacitively connected to the supporting track This may lea...

Page 13: ... to EN 61000 4 4 EN 61000 4 2 limit values in accordance with EN 50082 2 Installation location arbitrary Protection class IP20 PLC data Programmability via programming interface or RS485 interface TwinCAT BC TwinCAT Program size approx 3000 PLC statements Program memory 32 kbytes 96 kbytes Data storage 32 kbytes 64 kbytes Remanent flags 512 bytes Runtime system 1 PLC task PLC cycle time approx 3 m...

Page 14: ...efault settings the maximum value of the input output value is given by 7FFF hex Negative input output values such as 10V are represented as 8000 hex and intermediate values are correspondingly proportional to one another The full range of 15 bit resolution is not realized at every input output level If you have an actual resolution of 12 bits the remaining three bits have no effect on output and ...

Page 15: ...ions is said to be consistent The following consistency is required here 1 The high byte and low byte of an analog value word consistency 2 The control status byte and the corresponding parameter word for accessing the register The interaction of the peripherals with the control unit means that data can initially be guaranteed consistent only within an individual byte the bits which make up a byte...

Page 16: ...es at two different rates to indicate a fault whereby the specific error is encoded in the pattern of flashes as follows Flashing code Fast flashing Start of the error code First slow sequence Error code Second slow sequence Error argument Error code Error argument Description 1 pulse 0 1 2 EEPROM checksum error In line code buffer overflow Unknown data type 2 pulses 0 n n 0 Programmed configurati...

Page 17: ... operating conditions are indicated by the WD RX and TX LEDs PLC RUN The green PLC LED on the bus terminal controller lights up when the PLC task is in the RUN mode WD RX TX PLC RS485 LED Operating state WD off Controller operating as master RX blinks flickers The bus terminal controller is receiving data via the interface TX blinks flickers The bus terminal controller is sending data over the ser...

Page 18: ...n additional external device is connected to the RS485 port of the BC8000 It could be a display barcode scanner BK8000 or similar device Address selection 1 98 Programming mode RS485 BC8000 RS485 connection PC BC8000 or programming cable to the configuration port of the BC8000 RS485 RS232 The BC8000 is programmed in this mode There are two possible transmission paths 1 The RS485 interface of the b...

Page 19: ...C8000 Programming Instructions In order to simplify the process of programming the interface a flow diagram has been prepared to make the sequence clear To orient you you will find portions of this diagram repeated in the margin KL6001 operation For programming a KL6001 is used in order to be able to monitor the communication with the external serial device The terminal must be entered in the cont...

Page 20: ...0 IB502 Data in 1 IB503 Data in 2 IB504 Data in 3 IB505 Data in 4 QB500 Control byte QB501 Data out 0 QB502 Data out 1 QB503 Data out 2 QB504 Data out 3 QB505 Data out 4 The table shows the mapping of the interface emulation of the bus terminal controller The KL6001 0020 is exactly the same but at another address The terminal address depends on the socket position and on the other connected termin...

Page 21: ...f a parity framing or overrun error occurs the corresponding data is lost in transmission and will not be loaded into the reception FIFO buffer of the terminal If the buffer is full incoming data will be ignored After programming If programming is successful four steps must be followed 1 The absolute addresses in the BC8000 of the terminals must be adjusted only if the KL6001 is removed see append...

Page 22: ...n order for the rotary switch setting to be stored by the bus terminal controller a reset of the bus terminal controller must be carried out brief interruption of the power supply or software reset Address selector The Medium Plugs and Cables Cable connection is provided by a 9 pin D sub plug on the left side of the bus terminal controller A two conductor shielded cable can be used in which the sh...

Page 23: ...amming cable and analyzed there The programming system for Beckhoff bus terminal controllers is manufacturer independent according to IEC1131 3 The PLC programs can be written in 5 different programming languages IL FBD LD SFC ST In addition TwinCAT BC offers extensive debug functionalities breakpoint single step monitoring which facilitate commissioning Remanent Data Data that is to be retained a...

Page 24: ...tart at MB0 You first have to enable Retain Variables in order to achieve a storage increase through the Persistent Data By default no Persistent Variables are declared The Persistent Variable memory area must always be smaller or equal than that of the Retain Variables The KS2000 software allows this area to be increased to a maximum of 512 bytes Table 1 Register 18 These data are deleted by a ge...

Page 25: ... POS13 Analogue inputs 2 channels POS14 Power feed terminal POS15 Digital inputs 2 channels POS16 Digital inputs 2 channels POS17 Digital inputs 2 channels POS18 Digital outputs 2 channels POS19 Analogue outputs 2 channels POS20 KL6001_0020 standard 5 bytes user data With this configuration the bus terminal controller sets up the following assignment list POS21 End terminal In the BCXXXX bus termi...

Page 26: ... QB46 1 POS07 46 2 QB46 2 POS08 46 3 QB46 3 POS08 46 4 QB46 4 POS18 Portion for bit oriented data OUTPUT 46 5 QB46 5 POS18 Positions POS14 and POS21 are not relevant to data exchange They do not appear in the list If a byte is not fully utilized e g QB46 the bus terminal controller pads the remaining bits of the byte with zeros i Note If the KL6001 0020 is removed after successful programming of t...

Page 27: ...ister set has 64 registers and permits setting of various operating parameters for example selection of a thermocouple type or representation of the value in a different number format For further information refer to the corresponding documentation of the terminals Output byte 1 Output byte 0 empty Control byte I O bytes of an analog channel in the process image Input byte 1 Input byte 0 empty Sta...

Page 28: ...data bits odd parity 3 X 24 Stop bits 0 one stop bit 1 two stop bits 0 X From Firmware B2 Table 1 Register Characteristic Default 32 Baud rate 0 38400 baud 1 19200 baud 2 9600 baud 3 57600 baud 4 1200 baud 5 2400 baud 6 4800 baud 2 X 33 Mode 0 7 data bits even parity 1 7 data bits odd parity 2 8 data bits no parity 3 8 data bits even parity 4 8 data bits odd parity 2 X 34 Stop bits 0 one stop bit ...

Page 29: ...enden ARRAY 0 6 OF BYTE start BOOL auxiliary variable set to FALSE for the first cycle i2 USINT i3 USINT Summe BYTE checksum Timer1 TON starts transmission every 500 ms Starten BOOL set TRUE every 500ms until all data have been sent J0 UINT t1 INT byAusgang1 ARRAY 0 20 OF BYTE EingWorte USINT END_VAR MAIN program ComControl Sending IF NOT start THEN Initialization of the array for the BK8000 proto...

Page 30: ...fer IF Receive ByteReceived THEN waits until data have arrived byAusgang1 t1 Receive ReceivedByte byausgang1 t1 IF byAusgang1 0 16 70 THEN If the start marker is not recognized the program exits the loop EXIT END_IF EingWorte byAusgang1 1 t1 t1 1 END_IF UNTIL rxBuffer count 0 END_REPEAT IF T1 5 2 EingWorte THEN T1 0 END_IF byAusgang0 ROL ByAusgang1 5 byEingang0 Global variables VAR_GLOBAL Address ...

Page 31: ...s are fixed and can not be changed It is also necessary that the lengths of the input and the output data agree A BK8000 is entered into the System Manager and terminals can be selected as shown in the figure below in order to reach the 16 bytes of input and output Four KL3002s yield 16 bytes Which terminal is used is not significant as it can be renamed in the System Manager What is important tha...

Page 32: ...ipoint address must correspond with the address of the Bus Terminal Controller In order to make changes to the register settings it is necessary to lift the write protection in the KS2000 software Register Description Value range Default values 0 Offset of the PLC variables inputs 0 511 128 1 Length of the PLC variables inputs 0 511 16 2 Offset of the PLC variables outputs 0 511 128 Table 1 3 Leng...

Page 33: ...ack on I O RUN and ERR flash simultaneously manufacturer s setting active You can now continue as usual Mapping of the digital and the byte oriented Bus Terminals onto a fixed address Problem You want a constant start address for the digital inputs and outputs Solution With the KS2000 software you can enter an offset start value for the digital inputs and outputs in table 0 The byte oriented Bus T...

Page 34: ...ctified by triggering a short refresh of the K Bus The setting can be carried out with the KS2000 software Table 1 register 17 LowByte cycle time to K Bus refresh 80 ms HighByte Retries Recommendation Enter 0x0350 in table 1 register 17 i e three retries all at 80 ms Note that this causes the Bus Terminal watchdog to increase to 240 ms during a fault condition this is not true in case of a K Bus e...

Page 35: ...rminals 30 31 Mechanical construction 8 Number of stations 20 Persistent Data 20 PIN assignment 19 PLC data 10 PLC LED 14 Power contacts 4 5 8 Power supply 5 Process image example 22 Programming Example 26 Read out address 25 Remanent Data 20 RS485 cable 19 Slave 28 Starting operation 13 Technical data 10 TwinCAT 28 Word alignment 11 If you have suggestions to make or ideas about our documentation...

Page 36: ...there Beckhoff Headquarters Beckhoff Automation GmbH Eiserstr 5 33415 Verl Germany phone 49 0 5246 963 0 fax 49 0 5246 963 198 e mail info beckhoff com web www beckhoff com Beckhoff Support Support offers you comprehensive technical assistance helping you no only with the application of individual Beckhoff products but also with other wide ranging services support design programming and commission...

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