BK3520 | PROFIBUS “Economy plus” Bus Coupler, fibre optic.
The BK3520 “Economy plus” Bus Coupler links a fiber optic PROFIBUS system to the modular, extendable electronic Bus Terminal system. With the K-bus extension technology up to 255 spatially distributed Bus Terminals can be connected to one Bus Coupler.
The particular feature for the BK3520 Bus Coupler is its fiber optic connection and its high transmission rate of up to 12 Mbaud. The fiber optic link guarantees that the transmission is free from electromagnetic interference and provides full electrical isolation.
An interface-module is necessary to translate between the physical properties of RS485 to those of an underlying optical fiber ring. The topology corresponds with the RS485 physics (line topology). For this reason, the BK3520 possesses two transmitters and two receivers. The address is set by the address selection switch. The baud rate is automatically recognized. Baud rates of up to 12 Mbaud are supported, so that the transmission speed can be adapted to meet the needs of the particular technical process.
The “Economy plus” Bus Coupler has been designed to accommodate automation requirements. PROFIBUS protocols omit FMS operation in order to be able to transfer more user data in DP mode. The BK3520 incorporates the PROFIBUS DP V1 services.
| System data | PROFIBUS | BK3520 |
|---|---|
| Number of I/O stations | 100 with repeater |
| Number of I/O points | approx. 6,000, depending on the master |
| Data transfer medium | APF (plastic) fibre (1,000 µm) |
| Max. cable length | 40 m between two stations |
| Data transfer rates | up to 12 Mbaud |
| Technical data | BK3520 |
|---|---|
| Number of Bus Terminals | 64 (255 with K-bus extension) |
| Max. number of bytes fieldbus | 128 byte input and 128 byte output |
| Digital peripheral signals | 1,020 inputs/outputs |
| Analog peripheral signals | 64 inputs/outputs |
| Data transfer rates | automatic detection up to 12 Mbaud |
| Bus interface | 4 x HP-Simplex sockets (HP-Simplex plugs ZS1031-3500 included) |
| Topology | line topology |
| Data transfer medium | APF (plastic) fibre (1,000 µm) |
| Power supply | 24 V DC (-15 %/+20 %) |
| Input current | 70 mA + (total K-bus current)/4, 500 mA max. |
| Current supply K-bus | 1750 mA |
| Power contacts | max. 24 V DC/max. 10 A |
| Electrical isolation | 500 V (power contact/supply voltage/fieldbus) |
| Distance between stations | 40 m |
| Weight | approx. 170 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 |
| EMC immunity/emission | conforms to EN 61000-6-2/EN 61000-6-4 |
| Protect. class/installation pos. | IP 20/variable |
| Approvals/markings | CE, UL, ATEX |
| Ex marking | II 3 G Ex nA IIC T4 Gc |
