CNT-SVX09E-EN
19
Network Variable Bindings
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 MP581 and then
select the MP503. The Rover service tool shows only the variables in the MP503 of the SNVT that
matches the variable selected in the MP581.
shows the required bindings.
Table 5.
Bindings for example 3
Custom programming in the MP581 controls nvoSwitch01. Write a custom program to control
nvoSwitch01
ON
when the AHU is
ON
and
OFF
when the AHU is
OFF
. The network binding passes
the command to the binary output on the MP503.
Example 4: Use a Sensor Reading on a MP503 to Control a Pump VFD on a MP581
In this example, an MP581 is controlling the variable frequency drive (VFD) of a chilled water pump.
Use a differential pressure sensor (4–20 mA output) to control the speed of this pump.
Unfortunately, the differential pressure sensor is located more than 1000 ft. away from the pump,
therefore, it cannot be wired directly to the universal input on the MP581. Install an MP503 to read
the differential pressure and then use network bindings to send the pressure value to the MP581
controlling the chilled water pump VFD.
shows the LonTalk network for this example.
Figure 9.
LonTalk network for example 4
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 and then
select the MP581. The Rover service tool shows only the variables in the MP581 of the SNVT that
matches the variable selected in the MP503.
shows the required bindings.
Table 6.
Bindings for example 4
Network Variable Output on the
MP581
Binding To
Network Variable Input on the
MP503
nvoSwitch01
(a)
(a) The MP581 has 40 generic binary (SNVT_switch) network variable outputs available for binding (nvoSwitch01 through
nvoSwitch40).
nviBOP1Request
Network Variable Output on the
MP503
Binding To
Network Variable Input on the
MP581
nvoCurrent1
nviCurrent_mA01
(a)
(a) The MP581 has 8 generic current (SNVT_amp_mil) network variable inputs available for binding (nviCurrent_mA01 through
nviCurrent_mA08).
®
LonTalk link
Tracer MP503
Tracer MP581 with
operator display
Additional
LonTalk
devices
