SEW-Eurodrive DH 21B Series, Manual, Page: 56 / 92

7 Project planning and startup with MOVITOOLS
®
MotionStudio
Startup of the fieldbus at the DHR21B/41B controller
Manual – DHE/DHF/DHR21B (standard) and DHE/DHF/DHR41B (advanced)
56
Each decimal number stands for one byte (= 8 bits) of the address and can also be
represented using binary code (see following table).
Byte 1 Byte 2 Byte 3 Byte 4
11000000 . 10101000 . 00001010 . 00000100
The IP address comprises a network address and a node address (see following
table).
Network address Node address
192.168.10 4
The part of the IP address that denotes the network and the part that identifies the
node is determined by the network class and the subnet mask.
Node addresses cannot consist of only zeros or ones (binary) because they represent
the network itself or a broadcast address.
Network classes
The first byte of the IP address determines the network class and as such represents
the division into network addresses and node addresses.
Value
range Network
class
Complete network ad-
dress
(Example)
Meaning
Byte 1
0 – 127 A 101.22.3 10 = Network address
1.22.3 = Node address
128 – 191 B 17216.52.4 172.16 = Network ad-
dress
52.4 = Node address
192 – 223 C 192.168.10.4 192.168.10 = Network ad-
dress
4 = Station address
This rough division is not sufficient for a number of networks. They also use an expli-
cit, adjustable subnet mask.
Subnet mask
A subnet mask is used to divide the network classes into even finer sections. Like the
IP address, the subnet mask is represented by 4 decimal numbers separated by
decimal points.
Example: 255.255.255.128
Each decimal number stands for one byte (= 8 bits) of the subnet mask and can also
be represented using binary code (see following table).
Byte 1 Byte 2 Byte 3 Byte 4
11111111
. 11111111
. 11111111 . 10000000
22900055/EN – 08/2016