TFxB Series Thermostat Controller
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2) Enter the password (637).
3) In this mode you can manually configure the MAC address, Device Instance and Baud Rate.
4) Power down the thermostat controller, connect it to the network and then power up the unit.
5) Repeat steps 1 to 4 for each thermostat controller.
6) To increase network efficiency or if there are less than 127 devices on the network, the Max_Master
value can be configured through WriteProperty service to the
Device Object.Max_Master
. For more
information, refer to the
MAC address and Max_Master
section on page 4.
Copy Config
Copy the thermostat controller’s entire configuration and broadcast it to other thermostat controllers of the same
type on the same network.
1) With the thermostat controller in Operation Mode (jumper = RUN), go to the Quick Access Menu by
pressing and holding both function buttons on the thermostat for 5 seconds. Refer to the
Specification &
Installation Manual
for more details.
2) Enter the password (637).
3) Scroll to “Copy Config” and select yes. Follow onscreen instructions.
MAC address and Max_Master
The MAC address must be unique on the entire MS/TP network. However, having a unique MAC address and a
high baud rate does not guarantee efficient operation of the thermostat controller and other MS/TP units on the
MS/TP network. Some MAC address and Max_Master combinations are more efficient than others. BACnet
®
requires token-passing units to occasionally “poll” for other masters based on the MAC address and
Max_Master. A “poor” combination of MAC addresses and Max_Master can lead to a slower network due to lost
time polling for masters that are not present. Unless there are 126 other units on the MS/TP network, the default
Max_Master of 127 is not the most efficient choice for the thermostat controller. The Max_Master default of 127
was selected to ensure that any master, specifically a BACnet
®
client, can be found when the thermostat
controller is first started.
Example 1:
This example is slow and inefficient because every time either unit is required to find another master unit it has
to poll 126 units until it finds the right one to pass the token.
MAC=0.
Max_Master=127
MAC=1,
Max_Master=127
Example 2:
This example is better but it’s still slower. The Max_Master is set to the most efficient value; however because
of the gap between the two MAC addresses, each unit must poll 4 units until it finds the right one to pass the
token.
MAC=0.
Max_Master=5
MAC=1 to MAC=4 are not used
MAC=5,
Max_Master=5
Example 3:
This example is an incorrect configuration. The MAC=0 will never find MAC=2 because it will never poll for the
master MAC address=2.
MAC=0.
Max_Master=1
MAC=2,
Max_Master=2
Example 4:
As a general guideline, the most efficient set up for an MS/TP network is one in which the units are
consecutively numbered starting at MAC address 0 and all have Max_Master=the maximum MAC address in
the system. If consecutive numbering is not possible, then the next most efficient set up is one in which all units
have Max_Master=the maximum MAC address in the system.
MAC=0.
Max_Master=3
MAC=1,
Max_Master=3
MAC=2,
Max_Master=3
MAC=3,
Max_Master=3
