Siemens SITRANS Probe LR Manuel D'utilisation page 15

If SITRANS Probe LR displays an incorrect full level, or if the reading fluctuates between a
false high level and a correct level, use P838 and P837 together to prevent false echo
detection. They elevate the TVT in this region and de-sensitize the receiver from any 'base
noise' caused by internal antenna reflections, nozzle echoes, or other vessel false echoes
P838 sets the distance within which SITRANS Probe LR will learn a new echo profile. P837
instructs the Probe LR to learn the echo profile at that moment, and use the learned profile
instead of the default TVT curve.
a. Perform this function when the vessel is empty or nearly empty.
b. First rotate the instrument for best signal (lowest false echo amplitude).
c. Determine the distance from the reference point to the material level, and subtract 0.5 m
(1.6 ft).
d. Select P838 and key in [distance to liquid level minus 0.5 m/1.6 ft ], and press ENTER
e. Select P837, then press 2 (Learn) and ENTER
Learned TVT) after a few seconds.
9. Return to RUN
Press PROGRAM
SITRANS Probe LR Communications: HART
mA Output with Level, Space, and Distance operation
See
Note:
illustration of the mA output with different modes of operation.
• You will need the full manual (Part#: 7ML19985HR0x) to acquire the list of applicable
parameters.
• The HART Electronic Device Description (EDD) may be obtained from the HART
Communication Foundation at www.hartcomm.org.
• We recommend that you use SIMATIC Process Device Manager (PDM) to program your
instrument.
Maintenance
SITRANS Probe LR requires no maintenance or cleaning under normal operating conditions. If
cleaning becomes necessary under severe operating conditions:
1. Note the antenna material and the process medium, and select a cleaning solution that
will not react adversely with either.
2. Remove the instrument from service and wipe the antenna clean using a cloth and
suitable cleaning solution.
Unit Repair and Excluded Liability
For detailed information, please see the inside back cover.
1.
For more details on Auto False Echo Suppression, please see the full manual.
7ML19985QP81
to return to RUN mode: setup is complete.
SITRANS Probe LR – QUICK START MANUAL
. P837 will automatically revert to 1 (use
on page 11 for an
1
.
.
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