Delta AH500 series, Руководство по эксплуатации оборудования

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A H 5 0 0
Hardware and Operation Manual
9 - 4
DHCP is a protocol for assigning dynamic IP addresses to
ports in a network.
I
f
a server using DHCP
assigns
an IP address to a port, it assigns a dynamic IP address to the port. In NWCONFIG, the ports which are
assigned dynamic IP addresses can not
connect to any network.

Subnet mask
A
sub
net mask is a
mask used to determine what subnet an IP address belongs to
. T
he ports in a network
are assigned the same sub
net mask. B
esides, if the devices in a network want to perform data exchange,
they must be in the same domain.

PLC Link
A
PLC Link is a network mechanism for data exchange performed through an RS
-
485 cable. If there are
several nodes in an RS
-
485 network, users can create a mechanism for data exchange in the network. If
the parameters which are set are downloaded to the PLC which functions as a master station, the system
of the PLC
will
perform data exchange through special relays and special registers when the PLC runs.
A PLC Link is a master/slave model
. T
here is only one mast
er station in an
RS
-
485 network, and the
other stations which are slave stations passively receive reading/writing commands from the master
station. The slave stations can not exchange data.
T
hey have to exchange data through the master
station.

Ether Link
An Ether Link is a network mechanism for data exchange performed through an Ethernet connection. I
f
there are several nodes in an Ethernet network, users can create a mechanism for data exchange in the
network
, and select a start mode. If the parameters which are set are downloaded to the PLCs in the
network, the system
s
of the PLC
s
perform data exchange according to the start mode selected when the
PLC
s run.
Besides, only AH500 series CPU modules support Ether Links.
An Ether Link is not a master/slave model. I
t allows a
node to send reading commands which ask for data
to other nodes.
T
he nodes will send the data to the node after they receive the reading commands
.
O
wing
to the fact that a node can not send writing commands to other nodes,
t
he use of an Ether Link is safer
than the use of a PLC Link.
B
esides, the system automatically manages the transmission of packets
through TCP/IP. Compared with a PLC Link, an Ether Link is more efficient.
*. Please refer to related books or technical documents for more information about RS-485 and Ethernet.
9.1.3 Communication Setting in NWCONFIG
NWCONFIG is used to configure a network. When users configure a network, they have to download
parameters to the nodes in the network, upload parameters from the nodes in the network, or monitor nodes in
the network.
T
he nodes in the
network
s created in NWCONFIG may include a device which is not the device
for which the ISPSoft project is created, and therefore users have to set the communication parameters in the
device
.
In order to help people select appropriate parameters, the communication mechanism in NWCONFIG
is introduced before communication setting is described.