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CNT-SVX09E-EN
Network Variable Bindings
Examples of Network Variable Bindings
The following examples show four (4) common uses of bindings in MP503 applications.
Example 1: Display Sensor Readings from a MP503 on a MP581 Operator Display
In this example, four different sensors are connected to a MP503. A thermistor reading the outside
air temperature is connected to universal input 1 on the MP503. A 4–20 mA sensor reading the
outside air humidity is connected to universal input 2. Two binary inputs from a fire panel (Alarm
Status and Fire Panel Trouble) are connected to universal input 3 and universal input 4,
respectively. An MP581 is on the same LonTalk link as the MP503. The MP581 is controlling an air-
handling unit (AHU). The outside air enthalpy is required to control the economizer on the AHU.
The building operator also wants to know the outside air temperature and humidity, so those
values should be displayed on the operator display of the MP581. The location of the outside air
sensors make it convenient to wire those points to the MP503.
Use bindings to allow the economizer control in the MP581 to calculate outside air enthalpy and
to display the four inputs from the MP503 on the operator display of the MP581.
the LonTalk network for this example.
Figure 6.
LonTalk network for example 1
®
LonTalk link
Tracer MP503
Tracer MP581 with
operator display
Additional
LonTalk
devices
Use the Rover service tool to create bindings. (Refer to the
Rover Operation and Programming
Guide (
EMTX-SVX01). Using the Rover service tool, select the network variable from the MP503
nvoVolts4
SNVT_volt
Universal Input 4 Status Output:
• Indicates the value of universal input 4 if it is configured
as 0–10 Vdc.
• If universal input 4 is not configured as 0–10 Vdc, this
output is -3276.8.
nvoBOP1Status
SNVT_switch
Binary Output 1 Status Output:
• Indicates the value of binary output 1.
nvoBOP2Status
SNVT_switch
Binary Output 3 Status Output:
• Indicates the value of binary output 2.
nvoBOP3Status
SNVT_switch
Binary Output 3 Status Output:
• Indicates the value of binary output 3.
nvoBOP4Status
SNVT_switch
Binary Output 4 Status Output:
• Indicates the value of binary output 4.
Table 2.
Tracer MP503 network variable outputs (continued)
Variable name
Data type
Description
