Vega VEGABAR 82 Operating Instructions Manual

Also see for VEGABAR 82: Product information Operating instructions Quick setup guide Operating instructions Operating instructions

Contents

7310 SupplementVEGABAR 82 • Modbus and Levelmaster protocol46294-EN-171120Electrical protective measures9)Housing material Protection acc. to IEC 60529 Protection acc. to NEMAPlastic IP 66/IP 67 Type 6PAluminium IP 66/IP 67IP 66/IP 68 (0.2 bar)Type 6PType 6PStainless steel, precision casting IP 66/IP 67IP 66/IP 68 (0.2 bar)Type 6PType 6PStainless steel (transmitter, versionwith external housing)IP 68 (25 bar) -Connection of the feeding power supplyunitNetworks of overvoltage category IIIAltitude above sea levelƲ by default up to 2000 m (6562 ft)Ʋ with connected overvoltage protection up to 5000 m (16404 ft)Pollution degree10) 4Protection rating (IEC 61010-1) IIApprovalsInstruments with approvals can have different technical specifications depending on the version.For that reason the associated approval documents of these instruments have to be carefullynoted. They are part of the delivery or can be downloaded under www.vega.com, "Instrumentsearch (serial number)" as well as in the download area.10.2 Basics ModbusBus descriptionThe Modbus protocol is a communication protocol for the communication between instruments. It isbased on a Master/Slave or Client/Server architecture. By means of Modbus, a Master and severalSlaves can be connected. Each bus participant has an unambiguous address and can send mes-sages to the bus. This is initiated by the Master, the addressed Slave answers. For data transfer, theversions serial (EIA-485) as well as the mode RTU are available. In the RTU and ASCII mode inter-esting here, data will be transmitted in binary form. The telegram consists generally of the address,the function, the data as well as the transmission check.Bus architectureIn the version Modbus RTU, up to 32 participants can be connected to the bus. The length of thetwisted two-wire cable can be up to 1200 m. The bus must be terminated on both sides at the lastbus participant with a terminating resistor of 120 Ohm. The resistor is already integrated in theVEGABAR 82 and is activated/deactivated via a slide switch.9) Protection rating IP 66/IP 68 (0.2 bar) only in conjunction with absolute pressure.10) When used with fulfilled housing protection.