Hach AquaTrend 51200, Instrument Manual

Page: 20 / 94

Page 20
Network Design
51350-18 Aquatrend Interface Network.fm
Section 2
2.2.8 Digital Display Module (DDM)
The Digital Display Module (DDM) is an eight-character display that can be
attached to sensors to provide a local digital reading. Once the display is
added to the network and assigned to the sensor by the Master AquaTrend
Interface, it will automatically display data from the sensor. For sensors that
have multiple parameters (measurements), you can choose which parameter
you want to display on the DDM. See the
Digital Display Module Manual for
detailed information.
2.2.9 Repeater Module
The AquaTrend Repeater module is a physical layer repeater used to extend
the length of the AquaTrend Network by a maximum of 500 meters. A total of
three such devices can be installed on the AquaTrend Network to extend the
total length of the network to 2000 meters.
2.3 Network Design
Based on Wiring Topologies on page 83 , determine the appropriate
configuration for your operation by considering the following criteria;
descriptions of each device is given in
section 2.2 .
Note: All AquaTrend Interfaces on a
system display measurements and
menus, but only the Master
AquaTrend Interface can perform
network operations through the
Network Menu.
The system can contain as many as nine AquaTrend Interfaces but only
one can be the Master AquaTrend Interface. Each AquaTrend Interface
is programmed in an undetermined state when shipped from the factory
and must be designated as a Master or Remote when initially attached to
the network.
If more than one AquaTrend Interface is to be attached to the network,
the Master AquaTrend Interface will be designated before other
AquaTrend Interfaces are added. Additional AquaTrend Interfaces will be
designated as Remotes.
Select the number of PS1201s based on the wattage needed and the
distance between the power supplies and the devices. Each PS1201
Power Supply provides 25 watts. Available devices and their wattages are
listed below and in the PS1201 manual.
If a system larger than 35 nodes is needed, refer to the information on
assigning subnet addresses in
Appendix A Use of Subnets on page 75 .
Table 7 Maximum Network Capabilities
Device
Number of devices that can be maintained on one
AquaTrend Interface Network
Signal Output Module (SOM) 8
Serial I/O Module (SIO) 2
Digital Display Module (DDM) 8
Sensors (A SIM is seen by the network as a sensor.
Maximum s SIMs = 8)
8
AquaTrend Interface 1 Master, 8 Remotes