"Topics" are the communication properties and addresses that are used in the Wonderware application.
Each communication route between the various elements must be identified separately, and are given
Upon selecting "New..." or "Modify...” the following appears:
- Enter the name to be assigned. This name must be referred back to in the
- Enter the communication port over which the DL3500 communicates with the MMI.
- Enter the protocol with which the MMI communicates with the DL3500.
- (this setting appears within the "Network Addressing" section.)
The appropriate choice depends on the mode of the DL3500 unit, and the network architecture.
See the following two cases on setting the NODE number.
Case 1 - Typical Installation:
In a typical installation, a PLC is being accessed; therefore
the address entered under “node” is that of the PLC. The
InTouch program's tag describes the location within the
PLC data table where the device information is stored.
The InTouch program's tag describes the location within
the PLC data table where the device information is stored.
Case 2 - Accessing a Modbus Slave Device:
To monitor/control a Modbus
unit from the MMI, a converter
must be present in the network
to convert from DH+ to
Modbus. There are two ways
that the MMI may be set up to
perform monitoring and control
of the Modbus device(s):
a) The MMI's DL3500-DF1 unit may send and receive messages directly to and from the DL3500-
Modbus Master (without going through the PLC to access the Modbus device(s). In this case, The
address entered is that of the DL3500-Modbus. The tag entered in the InTouch program must
provide the Modbus slave address (in dec) and the Modbus register location.
See DL3500-Modbus Master Application note for decoding
b) The MMI's may also access Modbus device information through the PLC. In this case, the address
entered is that of the PLC, and the InTouch program's tag describes the location within the PLC data
table where the Modbus device information is stored. When programming the PLC, it is crucial that
the MSG instruction be programmed to access the local node address of the DL3500-Modbus device
on the DH+ or DH-485 network, and the destination table address describe the Modbus address
See DL3500-Modbus Master Application note for decoding TAGS.