Emerson Rosemount Smart Wireless THUM, Reference Manual

Page: 40 / 60

Reference Manual
00809-0100-4075, Rev BA
October 2010
Smart Wireless THUM Adapter
5-2
STARTUP SEQUENCE
Because the THUM is a power scavenging device, different capabilities are
available at different times after startup. Configuration is available
immediately after startup and includes Update Rate and Discovery method.
All network settings including Network ID, Join Key can not be set until the
radio is completely initialized. This may take up to three (3) minutes after
startup.
After this amount of time has passed, the THUM adapter will start to join the
network. Time to join the network depends on network size and number of
devices and if active advertising is turned on in the Gateway. After sufficient
time to join has passed go to the Explorer page on the Smart Wireless
Gateway to see if the THUM has joined.
ADVANCED SETUP
Configure Advanced
Update Rate
The “Configure Update Rate” method sets all three update rates based on
one user input. The “configure Advanced Update Rate” method allows for
each update rate to be set independently of the other two. Values for all
update rates are between 8 seconds and 60 minutes. Only one update rate
can be set to 8 seconds.
In AMS Select Manual Setup and then the Wireless tab.
4-20 mA Current
This optimizes the THUM Adapter to the available loop current.
There are two options “Variable Current Mode” and “Fixed Current Mode”.
Variable current mode is the default mode and is used when the current on
the loop is changing between 3.5 mA to 25 mA.
Fixed Current mode is user selectable. This mode is for when the current on
the loop is fixed and will not drop below 15 mA. If the current drops below 15
mA when the THUM Adapter is in fixed current mode, there may be issues
with network traffic, and the THUM Adapter may drop off of the wireless
network. The HART loop will not be affected.
In AMS Select Manual Setup and then the Wired Device tab.
Voltage Drop
This optimizes the THUM Adapter to the available voltage on the loop. There
are two options: Variable and Fixed. Variable is the default mode. In Variable
mode the THUM drops between 2.25 V at 3.5 mA and 1.2 V at 25 mA. In
Fixed mode the THUM will always drop 2.25 volts. Fixed mode is used for
verifying that there is enough voltage on the loop in the loop check procedure.
In AMS Select Manual Setup and then the Wired Device tab.
Fast Keys
2, 2, 1,3
Fast Keys
2, 2, 2,1
Fast Keys
2, 2, 2,2