SMA2 User's guide in English
Contents
1. The new setting will be active immediately after transmission Use the Save parameters on EEPROM function set 01 in the register 48 to store the new value Configuration register default value 20h Absolute resolution 4D ro It allows to read the resolution of the absolute sensor 32hex Resolution 50 um max position 03 FF FFh 18 bits OAhex Resolution 10 um max position OF FF FFh 20 bits O5hex Resolution 5 um max position 1F FF FFh 21 bits O2hex Resolution 2 um max position 3F FF FFh 22 bits Othex Resolution 1 um max position 7F FF FFh 23 bits Preset Offset 51 53 rw This function is available only if the parameter Enable preset offset in the Configuration register is set to ENABLE Furthermore it has a double function depending on whether the parameter Set preset offset in the Configuration register is set to PRESET or OFFSET In the first case Set preset offset PRESET the Preset Offset register is used to set the preset value while in the second case Set preset offset OFFSET the Preset Offset register is used to set the offset value MAN SMA2 E 1 0 odt 21 www lika it www lika biz lika swn2 WARNING Activate the preset offset value only when the device is not moving Preset The Preset function is meant to assign a value to a desired physical position of the sensor The chosen physical position will get the value set next to this item and all2. 2 Enable preset offset Enable Disable 4 Notused Gray Binary 6 Counting direction Inverted o it affects the absolute position not the AB incremental signals Set preset offset This parameter is available only if the parameter Enable preset offset is set to ENABLE It allows to activate either the preset function Set preset offset PRESET or the offset function Set preset offset OFFSET the Preset or Offset value has to be set in the Preset Offset register After having enabled the preset offset functions Enable preset offset ENABLE this item allows to activate either the preset function or the offset function The value set in the Preset Offset register will have a different meaning depending on the value of this parameter whether it is set to PRESET 0 or OFFSET 1 In the first case Set preset offset PRESET the Preset Offset register is used to set the preset value while in the second case Set preset offset OFFSET the Preset Offset register is used to set the offset value To activate the preset offset value use the Save and activate Preset Offset function in the Command register set 02 in the register 48 For any information on the preset and offset functions refer to the Preset Offset register on page 21 Default O Preset Enable preset offset It enables disables the preset offset functions After having enabled the use of the functions y
3. for instance the scale is mounted contrariwise to the sensor or it is mounted upside down see the section 3 Mounting instructions on page 4 the scale magnetic surface is damaged somewhere the sensor is not working properly e frequency error the sensor is travelling too fast on the scale NOTE For any information on the structure of the position information word please refer to the section 5 2 MSB left aligned protocol on page 10 MAN SMA2 E 1 0 odt 12 www lika it www lika biz lika svaz 5 5 Helpful information e The zero setting Preset and Counting direction functions are not available e The position information increases when the sensor moves as indicated by the arrow in Figure 1 starting from a min value up to a max value min and max values depend on the specific MTA2 magnetic scale installed in your application e f required by your application at installation execute a zero setting Preset operation of the position read by the Master 5 6 Recommended SSI input circuit ENCODER SSI BISS ypriver MASTER DATA CLOCK CLOCK CLOCK MAN SMA2 E 1 0 odt 13 www lika it www lika biz lika swn2 6 BISS C mode interface Ordering code standard SMA2 17 SMA2 is a Slave device and complies with the BiSS C mode interface and the Standard encoder profile For detailed information not listed in this manual please refer to the official BiSS website www biss
4. 1 5 SMA2 G1 1 5 SMA2 BG 1 2 SMA2 GG 1 2 SMA2 G1 1 2 SMA2 BG 1 1 SMA2 GG 1 1 SMA2 G1 1 1 ei WARNING The position value issued by the sensor is expressed in pulses to convert the pulses into a metric measuring unit you must multiply the number of detected pulses by the resolution Example 1 SMA2 BG 1 50 detected pulses 123 position value 123 50 6150 um 6 15 mm Example 2 SMA2 BG 1 1 detected pulses 1569 position value 1569 1 1569 um 1 569 mm MAN SMA2 E 1 0 odt 11 www lika it www lika biz lika saa 5 3 Recommended transmission rates The SSI interface has a frequency of data transmission ranging between 100 kHz and 1 MHz The CLOCK signal and DATA signal comply with the EIA standard RS 422 The SSI clock frequency baud rate depends on the length of the cable and must comply with the technical information reported in the following table Cable length lt 400 kHz lt 300 kHz lt 200 kHz lt 400 m lt 100 kHz The time interval between two Clock sequence transmissions must be at least 16 us Tp gt 16 us Clock Tp 5 4 Error bit The error bit is intended to communicate the normal or fault status of the Slave q correct status no active error o an error is active e reading error the sensor is not able to read the scale correctly among the possible causes are the scale is not installed properly
5. ii V load l 4 OUT Lo Encoder bene circuit PTA Jas O e e SeeeeSs68 563992555 ov V encoder 5VDC 5 V load 5VDC 5 typically lout 40 MA max Max cable length 10 m 33 ft The max frequency allowed for the AB signals depends on the cable length and the applied load Thermal and short circuit protections are not provided MAN SMA2 E 1 0 odt 28 www lika it www lika biz lika saa 8 Error and fault diagnostics In case of wrong alignment between the sensor and the magnetic scale at power on or during operation the following errors may occur e when switching on the system an alarm is triggered through the dedicated bit the scale is not read correctly it may be due to one of the following reasons the scale is not mounted properly for instance the scale is mounted contrariwise to the sensor or it is mounted upside down see the section 3 Mounting instructions on page 4 the scale magnetic surface is damaged somewhere the sensor is not working properly this may cause invalid data to be transmitted as soon as the sensor is aligned correctly the error bit switches to high logic level e during operation an alarm is triggered through the dedicated bit as previously stated the scale is not read correctly it may be due to one of the following reasons the scale is not mounted properly for instance the scale is mounted contrariwise to the sensor or it is mounted upside down see the s
6. jasc s M A 2 xx software version Manufacturer ID 7E 7F ro These registers show the Manufacturer ID hexadecimal values are according to ASCII code C O O i ASCII L Li Lika Electronic MAN SMA2 E 1 0 odt 23 www lika it www lika biz lika sna 6 6 Application note Device communication specifications Clock Frequency min 200 kHz max 10 MHz BiSS Timeout auto adaptation to clock max 16 us Internal position update 30 kHz frequency 6 7 Examples All values are expressed in hexadecimal notation unless otherwise indicated 6 7 1 Setting the Configuration register 49 Bit O not used 0 Bit 1 Set preset offset PRESET Bit 2 Enable preset offset ENABLE 0 Bit 3 not used Bit 4 not used 0 Bit 5 Output code BINARY 1 Bit 8 Counting direction INVERTED 1 Bit 7 not used 0 01100000 60 hex DATA Tx writing the 49 Configuration register Save parameters on EEPROM MAN SMAZ E 1 0 odt 24 www lika it www lika biz lika saz 6 7 2 Setting the Preset Offset registers 51 53 After having enabled and chosen the PRESET function Enable preset offset ENABLE Set preset offset PRESET in the Configuration register see the previous section 6 7 1 Setting the Configuration register 49 you want to set and activate the new Preset value 100000 01 86 AOh DATA Tx aote Paes Offset registers 2 6 Save and activate
7. mechanical installation complies with the system requirements concerning distance planarity and parallelism between the sensor and the scale as shown in Figure 2 Avoid contact between the parts Fix the sensor by means of two M3 20 mm min long cylinder head screws inserted in the provided holes Recommended tightening torque 1 1 Nm Recommended minimum bend radius of the cable R 42 mm Please note that the MIA2 magnetic scale can be provided with a cover strip to protect its magnetic surface see the order code Therefore the distance between the sensor and the magnetic scale is different whether the cover strip is applied The allowed gap D see Figure 2 between the sensor and the scale must be in the range indicated in the following table Gap sensor MTA2 magnetic scale D without cover strip with cover strip 0 1 0 6 mm 0 004 0 024 0 1 0 4 mm 0 004 0 016 MAN SMA2 E 1 0 odt 5 www lika it www lika biz lika WARNING SMA2 Make sure the mechanical installation complies with the system requirements concerning distance planarity and parallelism between the sensor and the scale as shown in Figure 2 all along the whole measuring length Please note that the MTA2 magnetic scale can be fitted with two tracks an absolute track on one side and an incremental track on the other side Thus you must strictly comply with the mounting direction Distance from the scale D a 4 Tilt lt
8. the sensor and the magnetic scale are met all along the whole measuring length Mechanical plays compromise the correct operation Wear of the machine may increase the tolerances e the surface of the magnetic scale has to be regularly cleaned using a soft and clean cloth to remove dust chips moisture etc MAN SMA2 E 1 0 odt 30 www lika it www lika biz lika svaz 10 Troubleshooting The following list shows some typical faults that may occur during installation and operation of the magnetic measurement system Fault The system does not work no pulse output Possible cause e The scale and or the sensor are not installed properly The active surface of the scale does not match the sensitive part of the sensor or the sensor installation does not comply with the mounting direction For correct installation please refer to section 3 Mounting instructions on page 4 e A magnetic part or a protection surface is interposed between the sensor and the scale Only non magnetic materials are allowed between the sensor and the scale e Installation does not met the mounting tolerances between the sensor and the scale indicated in this guide During operation the sensor hit the surface of the scale check whether the sensor sensitive part is damaged Or the sensor is mounted too far from the scale e The sensor has been damaged by short circuit or wrong connection Fault The measured values are either inaccurate or not provided in
9. the whole length Possible cause e The mounting tolerances between the sensor and the scale are not met all along the whole measuring length For correct installation see the section 3 Mounting instructions e The sensor is not installed properly on the scale see the section 3 Mounting instructions e The connection cable runs near high voltage cables or the shield is not connected properly e Frequency error the sensor is travelling too fast on the scale e The frequency of the Master clock is set too high or too low and the transmission cannot be synchronized correctly see the sections 5 SSI interface and 6 BISS C mode interface e A section of the magnetic scale has been damaged mechanically or magnetically along the measuring length e The measuring error is caused by a torsion in the machine structure Check parallelism and symmetry in the movement of the machine For further information refer also to the section 8 Error and fault diagnostics on page 29 MAN SMA2 E 1 0 odt 31 www lika it www lika biz lika SMA2 11 Default parameters list BiSS C interface Parameters list Default value Command 00 Configuration 20 Bit O not used 0 Bit 1 Set preset offset 0 Preset Bit 2 Enable preset offset 0 Enable Bit 3 not used 0 Bit 4 not used 0 Bit 5 Output code 1 Binary Bit 6 Counting direction 0 Standard Bit 7 not used 0 Preset Of
10. unit providing protection means against waste especially swarf as turnings chips or filings should this not be possible please make sure that adequate cleaning measures as for instance brushes scrapers jets of compressed air etc are in place in order to prevent the sensor and the magnetic scale from jamming Make sure the mechanical installation meets the system s requirements of distance planarity and parallelism between the sensor and the scale indicated in Figure 2 all along the whole measuring length The Figure 1 shows how the sensor and the scale must be installed please note that the MTA2 magnetic scale can be fitted with two tracks an absolute track on one side and an incremental track on the other side Thus you must strictly comply with the mounting direction MTA2 magnetic scale can be provided with a cover strip to protect its magnetic surface see the order code The arrow indicates the standard counting direction increasing count with sensor moving as indicated by the arrow in the Figure for the BiSS version see the parameter Counting direction on page 21 the counting direction function is not available for the SSI interface MAN SMA2 E 1 0 odt 4 www lika it www lika biz lika swn2 WARNING The system cannot work if mounted otherwise than illustrated in Figure 1 3 3 Mounting the sensor 2 x M3 cylinder head screws 20 mm min long Mounting direction Incremental track Figure 1 Make sure the
11. 1 o E Figure 2 WARNING Lateral deviation Roll ji 1 gan T bl ki 0 3 mm Yaw 21 After having installed the sensor on the magnetic scale a zero setting Preset operation is compulsorily required The zero setting Preset operation is further required every time either the sensor or the scale is replaced The zero setting Preset function is available for the BiSS interface only refer to page 21 It is not available for the SSI interface SMA2 BG SMA2 GG SMA2 G1 MAN SMAZ E 1 0 odt 6 www lika it www lika biz lika svaz 4 Electrical connections WARNING Electrical connection has to be carried out by qualified personnel only with power supply disconnected and mechanical parts compulsorily in stop WARNING If wires of unused signals come in contact irreparable damage could be caused to the device Please insulate them singularly Connections Function M128 pin Data OUT Data OUT 1 AB incremental output signals are provided in specific versions only see the order code SMA2 G1 SSI interface MSB Left Aligned protocol Gray output code AB incremental SMA2 I7 BiSS interface C protocol AB incremental 4 1 M12 8 pin connector specifications M12 8 pin connector male frontal side A coding 4 2 M8 cable specifications Model LIKA HI FLEX M8 cable Wires 6x 0 14 mm 2 x 0 22 mm Shield tinned copper braid Extern
12. 4 02 6 8 Recommended BiSS input circuit VDriver ENCODER SSI BISS MASTER DATA CLOCK CLOCK CLOCK van V MAN SMA2 E 1 0 odt 25 www lika it www lika biz lika saa 7 AB incremental output signals WARNING AB incremental output signals are provided in specific versions only see the order code SMA2 G1 SSI interface MSB Left Aligned protocol Gray output code AB incremental SMA2 I7 BiSS interface C protocol AB incremental In addition to the absolute position information SMA2 sensor can provide two AB incremental signals through the NPN open collector output circuit They require 5VDC 5 power supply with lout 40 mA max Thermal and short circuit protections are not provided Please note that in this case the MTA2 magnetic scale is fitted with two tracks an absolute track on one side and an incremental track on the other side Thus you must strictly comply with the mounting direction For complete information refer to the section 3 Mounting instructions on page 4 and to the section 4 Electrical connections on page 7 In the following table the main features of the incremental measuring system are listed for each order code They concern the resolution i e the distance between two following edges of A and B channels the minimum edge distance i e the minimum spacing between two following signal edges at output the maximum counting frequency a
13. al diameter 5 3 mm 5 6 mm Conductor resistance lt 148 Q km 0 14 mm 90 Q km 0 22 mm Minimum bend radius Qx7 5 MAN SMA2 E 1 0 odt 7 www likait www lika biz lika 4 3 Ground connection SMA2 Minimize noise by connecting the cable shield and or the connector housing and or the sensor to ground Make sure that ground is not affected by noise The connection point to ground can be situated both on the device side and on user s side The best solution to minimize the interference must be carried out by the user 4 4 AB incremental output signals For any information on the AB incremental output signals refer to the section 7 AB incremental output signals on page 26 4 5 Features summary Order code Resolution pm Max travel speed m s SMA2 xx 1 50 50 7 SMA2 xx 1 10 10 7 SMA2 xx 1 5 5 7 SMA2 xx 1 2 2 2 8 SMA2 xx 1 1 1 1 4 MAN SMA2 E 1 0 odt 8 www lika it www lika biz lika swn2 5 SSI interface Order codes SMA2 BG SMA2 GG SMA2 G1 5 1 SSI Synchronous Serial Interface SSI the acronym for Synchronous Serial Interface is a synchronous point to point serial Ze en interface engineered for unidirectional data atounonouo conse ETERA transmission between one Master and one Slave Developed in the first eighties it is based on the RS 422 serial standard Its most peculiar feature is that data transmission is achieved by synchronizin
14. arf as turnings chips or filings should this not be possible please make sure that adequate cleaning measures as for instance brushes scrapers jets of compressed air etc are in place in order to prevent the sensor and the magnetic scale from jamming 2 Identification Device can be identified through the order code and the serial number printed on the label applied to its body Information is listed in the delivery document too Please always quote the ordering code and the serial number when reaching Lika Electronic for purchasing spare parts or needing assistance For any information on the technical characteristics of the product refer to the technical datasheet Warning devices having ordering code ending with Sxxx may have mechanical and electrical characteristics different from standard and be supplied with additional documentation for special connections Technical Info MAN SMA2 E 1 0 odt 3 www lika it www lika biz lika svaz 3 Mounting instructions WARNING Installation has to be carried out by qualified personnel only with power supply disconnected and mechanical parts compulsorily in stop 3 1 Overall dimensions 3 2 Magnetic scale The sensor has to be paired with the MTA2 type magnetic scale only For detailed information on the MTA2 type scale and how to mount it refer to the specific technical documentation Install the
15. country during device installation and operation e installation and maintenance operations have to be carried out by qualified personnel only with power supply disconnected and stationary mechanical parts e device must be used only for the purpose appropriate to its design use for purposes other than those for which it has been designed could result in serious personal and or the environment damage e high current voltage and moving mechanical parts can cause serious or fatal injury e warning Do not use in explosive or flammable areas e failure to comply with these precautions or with specific warnings elsewhere in this manual violates safety standards of design manufacture and intended use of the equipment e Lika Electronic assumes no liability for the customer s failure to comply with these requirements 1 2 Electrical safety e Turn OFF power supply before connecting the device e connect the unit according to the explanation in the section 4 Electrical connections e the wires of unused signals must be cut at different lengths and insulated singularly e in compliance with 2004 108 EC norm on electromagnetic compatibility following precautions must be taken 4 before handling and installing the equipment discharge electrical charge from your body and tools which may come in touch with the device power supply must be stabilized without noise install EMC filters on device power supply if needed always u
16. e Master Data bit structure bit 7 e 0 CRC 4 bits CRC namely Cyclical Redundancy Checking is the error checking field resulting from a Redundancy Checking calculation performed on the message contents This is intended to check whether transmission has been performed properly inverted output Polynomial X X 1 binary 10011 Logic circuit Input Data starts from MSB MAN SMA2 E 1 0 odt 17 www lika it www lika biz lika swn2 6 5 Used registers 49 4 Absolute resolution 58 All registers in this section are listed according to the following scheme Function name Address access Description of the function and default value Address register address expressed in hexadecimal notation Access ro read only rw read and write wo write only Default parameter values are written in bold Profile ID 42 43 ro These registers contain the identification code of the used profile 28 Hex 3 SMA2 17 1 2 SMA2 I7 1 1 See Standard encoder profile data format Variant 0 24 MAN SMA2 E 1 0 odt 18 www lika it www lika biz lika swn2 Serial number 44 47 ro These registers show the serial number of the device expressed in hexadecimal notation Register 44 year of production Register 45 week of production Registers 46 and 47 serial number in ascending order Command 48 wo Value Function oo Normal operati
17. ection 3 Mounting instructions on page 4 the scale magnetic surface is damaged somewhere the sensor is not working properly furthermore the alarm may be caused by a frequency error the sensor is travelling too fast on the scale The last valid position is frozen kept in memory until the next valid position is detected on the scale In the SSI interface the device status is transmitted via the error bit see the section 5 4 Error bit on page 12 In the BiSS interface the device status is transmitted via the nE bit see the Error bit on page 15 NOTE When the error bit has high logic level normal status no alarm active this means that the sensor is working properly and both the absolute position information and the incremental signals are output correctly Please note that the error bit is intended to communicate the status of both the absolute interface and the AB incremental signals For further information refer also to section 10 Troubleshooting on page 31 MAN SMA2 E 1 0 odt 29 www lika it www lika biz lika svaz 9 Maintenance The magnetic measurement system does not need any particular maintenance anyway it has to be handled with the utmost care as any delicate electronic equipment From time to time we recommend the following operations e periodically check the soundness of the structure and make sure that there are no loose screws tighten them if necessary e check the mounting tolerances between
18. fset 00 00 00 All values are expressed in hexadecimal notation MAN SMAZ E 1 0 odt 32 www lika it www lika biz This page intentionally left blank This page intentionally left blank This page intentionally left blank o To issue Dispose separately annan KA Lika Electronic Via S Lorenzo 25 36010 Carr VI Italy Tel 39 0445 806600 Fax 39 0445 806699 Italy eMail info lika it www lika it World eMail info lika biz www lika biz
19. g both the Master and the Slave devices to a common clock signal generated by the controller in this way the output information is clocked out at each controller s request Furthermore only two pairs of twisted wires are used for data and clock signals thus a six wire cable is required The main advantages in comparison with parallel or asynchronous data transmissions are e less conductors are required for transmission e less electronic components e possibility of insulting the circuits galvanically by means of optocouplers e high data transmission frequency e hardware interface independent from the resolution of the absolute encoder Furthermore the differential transmission increases the noise immunity and decreases the noise emissions It allows multiplexing from several encoders thus process controls are more reliable with simplified line design and easier data management Data transmission is carried out as follows At the first falling edge of the clock signal 1 the logic level changes from high to low the absolute position value is stored while at the following rising edge 2 the transmission of data information begins starting from the MSB 1 2 ae J TM clockK L aaa DATA MSB LS n ED A a X 3 X 2 x 1 A MAN SMA2 E 1 0 odt 9 www lika it www lika biz lika swn2 At each change of the clock signal and at each subsequent ris
20. gister see on page 23 to perform an automatic position control WARNING The use of both the Position control register and this Warning bit is strictly reserved to Lika Electronic technicians CRC 6 bits CRC namely Cyclical Redundancy Checking is the error checking field resulting from a Redundancy Checking calculation performed on the message contents This is intended to check whether transmission has been performed properly inverted output Polynomial X X 1 binary 1000011 Logic circuit Ist stage E O x Input Data starts from MSB 6 4 Control Data CD For complete CD structure information please refer to the official BiSS documents Protocol description C mode Main control data is described in this section Register address 7 bits This is the address of the register it specifies the register you need to read from or write to MAN SMA2 E 1 0 odt 16 www lika it www lika biz lika svaz RW 2 bits It sets whether you need to write to the register RW 01 or to read from the register RW 10 RW 01 when you need to write to the register RW 10 when you need to read from the register DATA 8 bit When writing to the register RW 01 this is the value to be set in the register i e transmitted from the Master to the Slave When reading from the register RW 10 this is the value to be read in the register i e transmitted from the Slave to th
21. ing edge 2 one bit is clocked out at a time up to LSB so completing the data word transmission The cycle ends at the last rising edge of the clock signal 3 This means that up to n 1 rising edges of the clock signals are required for each data word transmission where n is the bit resolution for instance a 13 bit encoder needs 14 clock edges If the number of clocks is greater than the number of bits of the data word then the system will send a zero low logic level signal at each additional clock zeros will either lead LSB ALIGNED protocol or follow MSB ALIGNED protocol or lead and or follow TREE FORMAT protocol the data word After the period Tm monoflop time having a typical duration of 12 usec calculated from the end of the clock signal transmission the encoder is then ready for the next transmission and therefore the data signal is switched high The clock signal has a typical logic level of 5V the same as the output signal which has customarily a logic level of 5V in compliance with RS 422 standard The output code can be either Binary or Gray see the order code 5 2 MSB left aligned protocol MSB left aligned protocol allows to left align the bits beginning from MSB most significant bit to LSB least significant bit MSB is then sent at the first clock cycle If the number of clock signals is higher than the data bits then unused bits are forced to logic level low 0 and follow the data word This protocol ca
22. interface com The device is designed to operate in a point to point configuration and has to be installed in a single Master single Slave network NOTE Never connect the sensor in a single Master Multi Slave network CLOCK and DATA signal levels comply with the RS 422 EIA standard 6 1 XML file The product is supplied with a XML file idbiss4C69 xml see enclosed support if provided or www lika biz gt LINEAR ENCODERS gt ABSOLUTE MAGNETIC SENSORS gt SMA2 Install the XML file in your BiSS Master device 6 2 Communication The BiSS C mode protocol uses two types of data transmission protocols e Single Cycle Data SCD this is the primary data transmission protocol It is used to transmit the process data from the Slave device to the Master device See the section 6 3 Single Cycle Data on page 15 e Control Data CD transmission of a single bit following the SCD data It is used to read data from or write data to the registers of the Slave See section 6 4 Control Data CD on page 16 Data SLO Tach SCD i wavatatatavalavalatalatatatatatatata F se Clock MA MAN SMA2 E 1 0 odt 14 www lika it www lika biz lika saa 6 3 Single Cycle Data SCD 32 bits consists of the following values 24 bit position value Position 1 error bit Error nE 1 warning bit Warning nW and CRC checking CRC 6 bits SCD structure bits 31 8 7 6 5 0 funct
23. ion Position Error_ Warning CRC Position 24 bits Process data to be transmitted from the Slave to the Master The transmission starts with the MSB most significant bit and ends with the LSB least significant bit bit 31 28 27 8 value 0000 MSB ISB To convert the position value into microns or millimetres multiply the received data value by the resolution see 4Dhex Absolute resolution register Example 1 SMA2 17 1 50 Absolute resolution 32 hex 50 dec detected pulses 123 position value 123 50 6150 um 6 15 mm Example 2 SMA2 17 1 1 Absolute resolution 01 hex 1 dec detected pulses 1569 position value 1569 1 1569 um 1 569 mm Error 1 bit This is intended to communicate the normal or fault status of the Slave nE 1 correct status no active error 0 error status an error is active e reading error the sensor is not able to read the scale correctly among the possible causes are the scale is not installed properly for instance the scale is mounted contrariwise to the sensor or it is mounted upside down see the section 3 Mounting instructions on page 4 the scale magnetic surface is damaged somewhere the sensor is not working properly e frequency error the sensor is travelling too fast on the scale MAN SMA2 E 1 0 odt 15 www lika it www lika biz lika svaz Warning 1 bit This is used along with the Position control re
24. lika sma2 User s guide SMA2 Description This guide is designed to describe the SMA2 series sensors These sensors are designed to measure linear displacements in industrial machines and automation systems The measurement system includes a magnetic scale and a magnetic sensor with conversion electronics The scale is magnetized with alternating magnetic north south poles and can be fitted with two tracks an absolute track on one side and an incremental track on the other side on specific models only The poles in the absolute track are coded thus the system provides an absolute position information As the sensor is moved along the magnetic scale it detects the displacement and yields an absolute SSI output information or a BiSS output information according to C mode specifications It can further provide additional AB incremental signals for speed feedback through the NPN o c output circuit The sensor has to be paired with the MTA2 type magnetic scale Table of contents 1 Safety summary Identification 3 Mounting instructions 4 Electrical connections 5 SSI interface 6 BISS C mode interface 7 AB incremental output signals 8 Error and fault diagnostics 9 Maintenance 10 Troubleshooting 11 Default parameters list MAN SMA2 E 1 0 odt 1 www lika it www lika biz lika svaz 1 Safety summary 1 1 Safety e Always adhere to the professional safety and accident prevention regulations applicable to your
25. n be used in sensors having any resolution The number of clocks to be sent to the sensor must equal the number of data bits at least anyway it can be higher as stated previously The great advantage of this protocol over the TREE format or the LSB RIGHT ALIGNED format is that data can be transmitted with a minimum time loss and Tm monoflop time can immediately follow the data bits without any additional clock signal The device uses a variable number of bits to provide the position information according to the resolution as shown in the following table Model en ne Length of the Max number of word information SMA2 BG 1 50 SMA2 GG 1 50 50 um 19 bits 18 bits 262143 SMA2 G1 1 50 SMA2 BG 1 10 SMA2 GG 1 10 10 um 21 bits 20 bits 1048575 SMA2 G1 1 10 SMA2 BG 1 5 SMA2 GG 1 5 5 um 22 bits 21 bits 2097151 SMA2 G1 1 5 SMA2 BG 1 2 SMA2 GG 1 2 2 um 23 bits 22 bits 4194303 SMA2 G1 1 2 MAN SMA2 E 1 0 odt 10 www lika it www lika biz lika sm2 SMA2 BG 1 1 SMA2 GG 1 1 1 um 24 bits 23 bits 8388607 SMA2 G1 1 1 The output code can be GRAY or BINARY see the order code The length of each information is equal to the resolution Structure of the position information SMA2 BG 1 50 SMA2 GG 1 50 SMA2 G1 1 50 SMA2 BG 1 10 SMA2 GG 1 10 SMA2 G1 1 10 SMA2 BG 1 5 SMA2 GG
26. nd the maximum travel speed i Minimum Max AB Resolution Max travel Order code edge frequency re la distance ps kHz p SMA2 G1 1 50 SMA2 17 1 50 50 0 25 73 7 SMA2 G1 1 10 SMA2 I7 1 10 10 0 25 350 SMA2 G1 1 5 SMA2 I7 1 5 5 0 25 580 7 SMA2 G1 1 2 SMA2 17 1 2 2 0 25 580 28 SMA2 G1 1 1 SMA2 17 1 1 1 0 25 580 1 4 Max counting frequency 4 MHz MAN SMA2 E 1 0 odt 26 www lika it www lika biz lika SMA2 Counting direction gt Please note that the incremental signals and their relationship with the pole pitch are represented schematically in the Figure above in the example the interpolation factor 4x is used The real interpolation factor results from the size expressed in pm of the pole pitch divided by the resolution of the specific sensor EXAMPLE Let s suppose we have a SMA2 G1 1 50 sensor Resolution 50 pm Pole pitch size in um 2000 pm for all SMA2 devices 2000 Interpolation factor o 40 Thus in the case of the SMA2 G1 1 50 sensor the system will provide 40 AB pulses per each pole NOTE Please note that the Counting direction parameter available in the BiSS C interface see on page 21 affects the absolute position information not the AB incremental signals MAN SMA2 E 1 0 odt 27 www lika it www lika biz lika svaz 7 1 Recommended input circuit de V
27. on Save parameters on EEPROM Save and activate Preset Offset Load and save default parameters After having set a new value in some register use the Save parameters on EEPROM function in this register to store it Set 01 in the register After having set a Preset Offset value use the Save and activate Preset Offset function in this register to both store and activate the preset offset at the same time Set 02 in the register Load and save default parameters default parameters are set at the factory by Lika Electronic engineers to allow the operator to run the device for standard operation in a safe mode As soon as the command is sent the default parameters are uploaded and activated All parameters which have been set previously are overwritten thus previously set values are lost The complete list of machine data and the relevant default parameters preset by Lika Electronic engineers are available on page 32 Set 04 in the register WARNING As soon as the Load and save default parameters command is sent all parameters which have been set previously are overwritten thus previously set values are lost As soon as the command is sent the register is set back to 00 Normal operation automatically Wait min 30 ms EPROM writing time before using a new function Default 00 MAN SMA2 E 1 0 odt 19 www lika it www lika biz lika saa Configuration 49 rw bit 0 bit 1 oO Notused Preset _ Offset
28. ou have to choose whether to activate the preset or the offset in the Set preset offset parameter Then to activate a new value set it next to the Preset Offset register and send the Save and activate Preset Offset command set 02 in the register 48 Default 0 enable Output code The sensor provides the absolute position information in the desired code format GRAY 0 or BINARY 1 Default 1 Binary MAN SMA2 E 1 0 odt 20 www lika it www lika biz lika saa Counting direction The standard counting direction is to be intended with sensor moving as indicated by the arrow in Figure 1 This parameter allows to reverse the counting direction In other words it allows the count up when the sensor moves in the reverse of the standard direction i e in the opposite direction to the one shown by the arrow in Figure 1 It is possible to choose the following options STANDARD 0 and INVERTED 1 When the counting direction is set to STANDARD Counting direction STANDARD the position information increases when the sensor moves according to the arrow in Figure 1 When the option INVERTED is set Counting direction INVERTED the position information increases when the sensor moves in reverse of the standard direction i e in the opposite direction to the one shown by the arrow in Figure 1 Default 0 Standard NOTE The Counting direction parameter affects the absolute position information not the AB incremental signals
29. se shielded cables twisted pair cables whenever possible avoid cables runs longer than necessary avoid running the signal cable near high voltage power cables mount the device as far as possible from any capacitive or inductive noise source shield the device from noise source if needed to guarantee a correct working of the device avoid using strong magnets on or near by the unit minimize noise by connecting the cable shield and or the connector housing and or the sensor to ground Make sure that ground is not affected by noise The connection point to ground can be situated both on the device side and on user s side The best solution to minimize the interference must be carried out by the user e do not stretch the cable do not pull or carry by cable do not use the cable asa handle MAN SMA2 E 1 0 odt 2 www lika it www lika biz lika saa 1 3 Mechanical safety e Install the device following strictly the information in the section 3 Mounting instructions e mechanical installation has to be carried out with stationary mechanical parts e do not disassemble the unit e do not tool the unit e delicate electronic equipment handle with care do not subject the device to knocks or shocks e protect the unit against acid solutions or chemicals that may damage it e respect the environmental characteristics of the product e we suggest installing the unit providing protection means against waste especially sw
30. set structure Use the Save and activate Preset Offset function set 02 in the register 48 to store and activate the new value The max allowed Preset value depends on the set resolution resolution 50 um D max preset 03 FF FFh 18 bits resolution 10 um D max preset OF FF FFh 20 bits resolution 5 um gt max preset 1F FF FFh 21 bits resolution 2 um gt max preset 3F FF FFh 22 bits resolution 1m gt max preset 7F FF FFh 23 bits The Offset value must be less than or equal to the difference between the overall position information 24 bits see Position and the max position information allowed by the set resolution see the Absolute resolution register Default OOh MAN SMA2 E 1 0 odt 22 www lika it www lika biz lika svaz Device type 55 ro This register describes the type of device Default 07h BISS linear encoder AB incremental signal SINE COSINE resolution 58 ro This register describes the period of the sine cosine signal Default OOh register not used Position control 59 rw This is used along with the Warning bit see on page 16 to perform an automatic position control Default 0Oh WARNING Do not change the value in this register its use is strictly reserved to Lika Electronic technicians Device ID 78 7D ro These registers show the Device ID hexadecimal values are according to ASCII code Reg 78 79 7A 7B 7C 7D _
31. the previous ad following positions will get a value according to it This function is useful for example when the zero position of the sensor and the zero position of the axis need to match The preset value will be set for the position of the sensor in the moment when the preset value is activated To activate the preset stop the sensor in the desired position enter the desired value next to this Preset Offset register and then send the Save and activate Preset Offset command in the Command register set 02 in the register 48 Offset The offset function is meant to assign a value to a desired physical position of the sensor so that the output position information is shifted according to the value next to this Preset Offset register The number of transmitted values will match the max number of position information as per the set resolution but the output information will range between the Preset Offset value minimum value and the sum of the max position information as per the set resolution see the Absolute resolution register the Preset Offset value maximum value The offset value will be set for the position of the sensor in the moment when the offset value is activated To activate the offset stop the sensor to the desired position enter the desired value next to this Preset Offset register and then send the Save and activate Preset Offset command in the Command register set 02 in the register 48 Preset Off
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