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With the K-bus extension technology, the “Economy plus” Bus Coupler BK2020 allows the connection of up to 255 spatially distributed Bus Terminals to one Bus Coupler. The “Economy plus” series supports all Beckhoff system Bus Terminals. It can process in its full configuration 1,020 digital signals and a maximum of 128 analog input and output channels per slave.
The Bus Coupler recognises the connected terminals and automatically generates the affiliations of the inputs/outputs to the bytes of the process image. The first input/output signal is inserted in the first bit of one byte (LSB), beginning from the left. The Bus Coupler inserts further signals in this byte. Inputs and outputs are clearly separated. The Bus Coupler automatically begins a further byte if the number of inputs or outputs exceeds 8 bits.
The Lightbus System is a rapid and safe serial fieldbus system. The Lightbus has a ring structure; up to 254 stations can be operated in a ring. Easy-to-operate standard fibre optic technology is used for data transmission, which represents excellent value. Thanks to an optimised, efficient telegram structure, the Lightbus achieves a very high user data transmission rate. For the exchange of 32 bit information 25 µs transmission time is required.
The BK2000 and BK2020 Bus Couplers support the operation of all Bus Terminals. As far as the user is concerned, handling of the analog inputs/outputs is not different to other series. The information is available in the process image of the controller for processing in the form of a byte array.
The analog and multi-functional Bus Terminals can be adapted to each specific application using the KS2000 configuration set. Depending on the type, the analog Bus Terminals' registers contain temperature ranges, gain values and linearisation characteristics. With the KS2000, the required parameters can be set on a PC. The Bus Terminals store settings permanently and in a fail-safe manner.
Optionally, the Bus Terminals can also be controlled by the control system. Via function blocks (FBs), the programmable logic controller (PLC) or the Industrial PC (IPC) handles configuration of the complete periphery during the start-up phase. If required, the controller can upload the decentrally created configuration data in order to centrally manage and store this data. Therefore, new adjustments are not necessary in the event of replacement of a Bus Terminal. The controller automatically sets the required setting on power up.
Thanks to the high-speed access method employed by the Lightbus, it is possible to access specific peripheral data and to read or write the required data only. Data is exchanged with the required priorities without producing any overhead.
| System data | Lightbus | BK2000, BK2010, BK2020 | ||
|---|---|---|---|
| Number of I/O stations | 254 | ||
| Number of I/O points | 16,192 | ||
| Data transfer medium | fibre optic conductor: APF (plastic) fibre (1,000 µm) or HCS fibre (200 µ) | ||
| Distance between stations | 45 m for APF fibre, 300 m HCS fibre | ||
| Data transfer rates | 2.5 Mbaud | ||
| Data transfer time | 0.26 ms in the case of 10 modules for 32 bit inputs and outputs each (without K-bus run-time) | ||
| Technical data | BK2000 | BK2010 | BK2020 |
|---|---|---|---|
| Number of Bus Terminals | 64 | 64 | 64 (255 with K-bus extension) |
| Max. number of bytes fieldbus | 512 byte input and 512 byte output | 32 byte input and 32 byte output | 512 byte input and 512 byte output |
| Digital peripheral signals | 512 inputs/outputs | 512 inputs/outputs | 1,020 inputs/outputs |
| Analog peripheral signals | 128 inputs/outputs | – | 128 inputs/outputs |
| Configuration possibility | via KS2000 or the controller | ||
| Bus interface | 2 x standard fibre optic connector Z1000 (plastic fibre), Z1010 (HCS fibre) | ||
| Power supply | 24 V DC (-15 %/+20 %) | ||
| Input current | 70 mA + (total K-bus current)/4, 500 mA max. | 70 mA + (total K-bus current)/4, 200 mA max. | 70 mA + (total K-bus current)/4, 500 mA max. |
| Starting current | approx. 2.5 x continous current | ||
| Recommended fuse | ≤ 10 A | ||
| Supply current K-bus | 1,750 mA | 500 mA | 1,750 mA |
| Power contacts | 24 V DC max./10 A max. | ||
| Electrical isolation | 500 Vrms (power contact/supply voltage) | ||
| Distance between stations | 45 m for APF fibre, 300 m HCS fibre | ||
| Weight | approx. 150 g | approx. 130 g | approx. 150 g |
| Operating/storage temperature | 0…+55 °C/-25…+85 °C | ||
| Relative humidity | 95 %, no condensation | ||
| Vibration/shock resistance | conforms to EN 60068-2-6/EN 60068-2-27/29 | ||
| EMC immunity/emission | conforms to EN 61000-6-2/EN 61000-6-4 | ||
| Protect. class/installation pos. | IP 20/variable | ||
| Accessories | |
|---|---|
| KS2000 | configuration software for extended parameterisation |
| Cordsets | cordsets and connectors |
| FC200x | PC Fieldbus Cards with PCI interface |
| C1xxx | PC Fieldbus Cards with ISA, VME bus, S5 interface |
| Ordering information | Description |
|---|---|
| BK2000 | Lightbus Bus Coupler for up to 64 Bus Terminals |
| BK2010 | Lightbus Bus Coupler for up to 64 digital Bus Terminals |
| BK2020 | Lightbus “Economy plus” Bus Coupler for up to 64 Bus Terminals (255 with K-bus extension) |
| BK2500 | Lightbus Bus Coupler with RS485 port instead of fibre optic interface |
| BC2000 | Lightbus Bus Terminal Controller |