No matter if star, line or tree topology, with the real-time Ethernet bus system VARAN, modular machine structures can easily become a reality. As a VARAN distributor, splitter modules are used. These route incoming data packages on to all out ports. The new splitter module VSV 046 enables the build-up of star and tree topologies and at the same time it takes over the power output for connected bus clients. It has a VARAN-In and five VARAN-Out ports.
Besides the bus signal, a 24V supply voltage can be provided. In this way peripheral devices can be connected and supplied with just the use of a hybrid cable, thus minimizing time and effort in the wiring process. The supply voltage at the individual out ports is turned on and off as needed by the control application. Optionally, a preferred VARAN out port can be used as an IP interface on the VSV 046. This enables the connection of service devices and allows an easy integration into a corporate network. VARAN offers the user the greatest possible freedom in machine and equipment design.
Facts VARAN bus
The VARAN bus is based on standard Ethernet physics. The protocol is implemented completely in the hardware at the FPGA level, trough which the CPU can be unburdened. The VARAN network organizes itself in the boot phase. The entire bus can be seen as a large memory area. The addresses of the individual bus participants are assigned automatically. Each user is assigned his own linear address space of 65,536 bytes during the start-up phase. Per network segment, up to 65,280 bus users can be managed this way.
VARAN uses short data packets with a maximum data length of 128 bytes, and thus can repeat messages in the same bus cycle if an error occurs . The unique VARAN feature of asynchronous direct access to a bus user at any time is only made possible through use of the small VARAN data frames. The VARAN bus operates in hard real- time with a bus cycle time of less than 100 µs and jitter of less than 100 ns.
Besides the standard communication, VARAN offers the possibility to transfer Safety data based on the “Black-Channel” Principal, whereby the bus does not assume any Safety-relevant tasks but serves as a transfer medium only. VARAN Bus is an open standard and manufacturer independent. The rights to the real-time Ethernet bus technology is held by an independent association, the VARAN Bus User Organization “VARAN-BUS-NUTZERORGANISATION” (VNO).