VEGA VEGAPULS 51K…54K Profibus PA - Manual (Page 31)

VEGAPULS 51P … 54P 31
24890-EN-041227
Electrical connection
4.2 Sensor address
In a Profibus system composed of Profibus
DP and Profibus PA subsystem, each partici-
pant must have a unique address. Each
participant, whether master or slave, is
accessed by means of its own address in
the bus system. The address of a partici-
pant, whether on DP or PA level, should be
assigned before connecting to the bus, be-
cause an address can be used only once. If
an address is used twice, bus interference
will result.
The address of a radar sensor can be set in
two ways:
- with the adjustment software VVO
(software addressing) or
- with the DIP switch block in the sensor
(hardware addressing).
VEGA Profibus sensors are delivered with
the address set at 126 (all DIP switches to
„ON“).
Remember, in a Profibus system there are
max. 126 participants possible. When the
DIP switch is set to address 126 (or higher),
the address can be adjusted with the adjust-
ment software PACTwareTM, the adjustment
module MINICOM or another configuration
tool (e.g. PDM). However, there can be only
one sensor on the bus with address 126
(delivery status) during address assignment
via software. For that reason, hardware ad-
dressing (DIP switch) before connection to
the bus is recommended.
Hardware addressing
The DIP switches generate an address
number in the binary system. This means
that, from right to left (ascending), any switch
represents a number twice as big as the
previous switch on the right. The corre-
sponding number in the decimal system
results from the sum of all switches set to
„ON“. In the illustration you see the decimal
number that corresponds to each individual
DIP switch.
DIP switch 8 corresponds to the number 128,
switch 1 corresponds to the number 1 and
switch 3 corresponds to the decimal number
4.
4
16
64
64 + 16 + 4 = 84
8 7 6 5 4 3 2 1
ON
1
2
4
8 16
32
64
128
8 7 6 5 4 3 2 1
Example 1
The switches 3, 5 and 7 are set to „ON“. The
address is then:
DIP switch 3 to „ON“ means 4
DIP switch 5 to „ON“ means 16
DIP switch 7 to „ON“ means 64
The sum is:
4 + 16 + 64 = Address 84