Configuration Types; Sensor Error Adjustment (Dtm Adjustment Function) - ABB ttr200 Operating Instruction

9.3

Configuration types

The device is listed with the FieldComm Group.
+
1
-
2 3
Fig. 13: Example for HART connection
1 Transmitter 2 Handheld terminal 3 HART modem 4 FDT /
DTM technology 5 Grounding (optional) 6 Power supply unit
(process interface)
1) If required
Manufacturer ID
Device Type ID
Profile
Configuration
Transmission signal
Operating modes
— Point-to-point communication mode – standard (general
address 0)
— Multidrop mode (addressing 1 ... 15)
— Burst mode
Configuration options and tools
— Device management / asset management tools
— FDT / DTM technology – via TTX200-DTM driver
— EDD - via TTX200 EDD driver
Diagnostic message
— Overrange / underrange in accordance with NE 43
— HART diagnosis
16 OI/TTR200-EN Rev. B | TTR200
6
R = 250 Ω 1)
b
5
4
A10081
0x1A
0x0D
HART 5.1
DTM
EDD
BELL Standard 202
9.3.1

Sensor error adjustment (DTM Adjustment function)

Sensor error adjustment can be performed in the DTM by
navigating to the menu path "Device / Maintenance /
Adjustment / Trim low or Trim high".
For sensor error adjustment, the sensor connected to the
transmitter must be brought to the lower range limit value
temperature / Trim low using a water quench or oven. It is
important to make sure the temperature is balanced and
stable.
In the DTM, check that the proper adjustment temperature has
been entered for the sensor before adjusting it. Based on the
comparison of the adjustment temperature entered (setpoints)
with the digital temperature measured by the transmitter,
which is available after linearization in the form of HART
temperature information, the transmitter calculates the
temperature deviation resulting from the sensor error.
During single-point adjustment, the temperature deviation
calculated results in an offset shift of the linear characteristic
output by the linearization module; the values of this
characteristic correspond to the HART signal or are sent to
the current output.
Sensor error two-point adjustment results in a change to the
offset and gradient due to the linear temperature value
characteristic output by the linearization module.
A pure sensor offset error can be corrected via the function
"Set lower range value" or the adjustment function "Trim low".
By contrast, if the error is not a pure sensor offset error, it can
only be corrected using two-point adjustment or two-point
calibration.