2 basics modbus – VEGA VEGAPULS SR 68 Modbus and Levelmaster protocol User Manual
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70
10 Supplement
VEGAPULS SR 68 • Modbus and Levelmaster protocol
41371-EN-130624
Ʋ mounted into the housing without
cover
IP 40
Materials
Ʋ Housing
ABS
Ʋ Inspection window
Polyester foil
Integrated clock
Date format
Day.Month.Year
Time format
12 h/24 h
Time zone Ex factory
CET
Measurement electronics temerature
Resolution
1 °C (1.8 °F)
Accuracy
±1 °C (1.8 °F)
Voltage supply
Operating voltage
8 … 30 V DC
Power consumption
< 500 mW
Interpolation protection
Integrated
Electrical protective measures
Protection, depending on housing version
Ʋ Plastic housing
IP 66/IP 67
Ʋ Aluminium housing, stainless steel
housing - investment casting, stain-
less steel housing - electro-polished
IP 66/IP 68 (0.2 bar)
4)
Ʋ Aluminium and stainless housing, in-
vestment casting (optionally available)
IP 66/IP 68 (1 bar)
Overvoltage category
III
Protection class
III
Approvals
Instruments with approvals can have different technical data depending on the version.
For that reason the associated approval documents of these instruments must be carefully noted.
They are part of the delivery or can be downloaded under www.vega.com and "VEGA Tools" as
well as under "Downloads" and "Approvals".
10.2 Basics Modbus
Bus description
The Modbus protocol is a communication protocol for the communication between instruments. It is
based on a Master/Slave or Client/Server architecture. By means of Modbus, a Master and several
Slaves 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 addessed Slave answers. The versions Ethernet
and serial (EIA-232 and EIA-485) as well as the modes ASCII, TCP and RTU are available for the
data transfer. In the RTU and ASCII mode interesting here, data will be transmitted in binary form.
4)
The prerequisites for maintaining the protection rating are a suitable cable as well as correct mounting.