WirelessHART Toxic & Combustible Gas Detector
IM_TCD50-10
www.ueonline.com/vanguard
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3.0 OPERATION
This device is for monitoring and communicating gas concentration levels for data collection or record keeping
and does not provide alarm signals.
Misuse of this product may cause explosion and/or personal injury. These instructions must be thoroughly read
and understood prior to installation of the unit.
The end-user is responsible for maintaining the device in full, operational condition.
This device is an explosion-proof and intrinsically safe, WirelessHART point gas detector used for the detection of
harmful gases in air, in order to help maintain a safe environment. Gas measurement readings are communicated along
with network and battery status via a local, digital display, and via WirelessHART 7.2 communication protocol.
3.1 Normal Operation
Under normal operation, the four variables (Table 2) are communicated via WirelessHART 7.2 communication protocol
every 8 seconds by default using burst message 0. The update rate is programmable from 8 seconds up to 3600 sec-
onds. Up to three burst messages (0-2) can be configured using the device descriptor. The burst message transmits a
chosen HART command to publish data. HART commands that can be burst include: 1, 2, 3, 9, 33, and 48. The default
configuration uses command 9.
Note: At the device, via the local, digital display, two variables are communicated by pushing the button once – the PV
and QV (see Table 2).
The following procedure should be used to configure a burst message:
1. Turn off any burst messages to be changed prior to configuration.
2. Select the burst message and Hart command for publishing. Consider what update rate is to be used based on
application. Faster update rates can impact battery life.
Note: A predefined setup can be used to automatically configure commands 9 and 48 for bursting with a default
update rate of 8 seconds.
3. Enable burst messages.
The following quick codes can be used to configure burst messages using a handheld device:
1. Burst Setup (9, 5, 1) - Allows configuration of the content of the burst message, and what update rates are to be
used.
2. Burst Mode Start/Stop (9, 5, 2) - Turns on/off publishing of a selected burst message.
3. Clear Burst Mode Data (9, 5, 3) - Resets any configuration performed on a burst message.
Note: Publishing must be turned off before a reset can be performed.
4. Burst Mode State (9, 5, 4) - Displays which burst messages are configured.
Device Variable
Process Variable
Units
Accessibility
Primary Variable (PV)
Gas Concentration
ppm, %LEL, %VOL,
or ppb
Read
Secondary Variable (SV)*
Temperature
Degrees C
Read
Tertiary Variable (TV)
Days Since Calibration
Days
Read
Quaternary Variable (QV)
Battery Voltage
Volts
Read
*Not available on the combustible sensor.
Table 2
