VEGA VEGASON 51P…53P Profibus PA - Manual (Page 5)

VEGASON 51P … 53P 5
Product description
1.2 Application features
Applications
• Level measurement of all liquids.
• Level measurement of solids (only short
meas. distances) such as e.g. coal, ore,
rocks, rock dust, cement, gravel, crushed
rock, sand, sugar, salt, cereals, flour, gran-
ules, powder, dust, sawdust, wood chips.
• Flow measurement on various flumes.
• Gauge measurement, distance measure-
ment, object monitoring and conveyor belt
monitoring
• Display of measured values integrated in
the sensor.
• Optional display separate from sensor.
Two-wire technology
• Supply and output signal on one two-wire
cable.
• Output signal and signal processing com-
pletely digital, therefore maximum accu-
racy.
• Profibus profile 3 – sensor.
Rugged and precise
• Measurement unaffected by substance
properties such as density, conductivity,
dielectric constant…
• Suitable for corrosive substances
• Measuring ranges 0.25 m … 15 m.
Adjustment
• With adjustment software VEGA Visual
Operating (VVO) on the PC
• With detachable adjustment module
MINICOM
• With Simatic-PDM adjustment program.
Connection to any process
• G 1 1 /
2
A, 1 1 /
2
“ NPT.
• G 2 A, 2“ NPT.
• Compression flange DN 100, ANSI 4“
Approvals
• CENELEC, ATEX, PTB, FM, CSA, ABS,
LRS, GL, LR, FCC.
1.3 Profibus output signal
PROcess FIeld BUS (PROFIBUS) is the re-
sult of a joint project of thirteen companies
and five universities. The companies Bosch,
Klöckner-Möller and Siemens played a deci-
sive role. The specifications of the bus are
described in the protocol layers 1, 2 and 7 of
the ISO/OSI reference model and are avail-
able from the PNO (Profibus user organisa-
tion). Layers 3 … 5 have not yet been
developed as a standard, leaving Profibus
with far-reaching perspectives for the future.
Today approx. 600 companies make use of
Profibus technology and belong to the PNO.
Profibus
FMS stands for Fieldbus Messaging
Specification, Profibus
DP for Decentralise
Periphery and Profibus
PA for Process Auto-
mation.
As a process automation bus, Profibus PA
enables power supply over the bus. Up to 32
sensors can be operated on a shielded two-
wire cable that carries both power supply
and measuring signal. In Ex areas, up to ten
sensors can be connected from the PA level
to one two-wire cable (EEx ia).
Bus structure
The DP and PA bus consists of up to 126
master and slave participants. Data are al-
ways exchanged from point to point, with the
data traffic being exclusively controlled and
checked by master devices. Communication
is carried out according to the Token-Passing
procedure. This means that the master own-
ing the Token, can contact the slaves, give
instructions, enquire data and cause the
slaves to receive and transmit data. After the
work is done or after a predetermined time
interval, the Token is passed on by the mas-
ter to the next master.