User's Manual

Parameter reference
SITRANS LR250 (HART)
Operating Instructions, 01/2014, A5E32220602-AB
141
TVT shaper (2.8.8.)
Note
•
The range is –100 to 100 bits. With 2 bits per dB this gives a range of –50 to 50 dB.
•
Shaper Mode (2.8.7.4.)
must be turned ON in order for TVT shaper points to be
transferred.
Adjusts the TVT (Time Varying Threshold) at a specified range (breakpoint on the TVT). This
allows you to reshape the TVT to avoid unwanted echoes. There are 40 breakpoints arranged in
5 groups. (We recommend using SIMATIC PDM to access this feature.)
To use TVT shaper via SIMATIC PDM:
1. Go to
Level Meter > Setup > Signal Processing > TVT setup > Shaper Mode
and select
On
.
2. Open the menu
Device – Echo Profile Utilities
and click on
TVT Shaper
. For more detail see
TVT shaper via SIMATIC PDM (Page 75).
To use TVT shaper via LUI (local user interface):
1. Go to
Shaper Mode (2.8.7.4.)
and select
On
.
2. Go to Breakpoint
1-9 (2.8.8.1.)
.
3. Open Shaper 1 and enter the TVT Offset value (between –50 and 50).
4. Go to the next Shaper point and repeat steps 3 and 4 until all desired breakpoint values have
been entered.
Breakpoint 1-9 (2.8.8.1.)
Values
Range: –50 to 50 dB
Default: 0 dB
Breakpoint 10-18 (2.8.8.2.)
Values
Range: –50 to 50 dB
Default: 0 dB
Breakpoint 19-27 (2.8.8.3.)
Values
Range: –50 to 50 dB
Default: 0 dB