Flow; Flow Calculation; Totalizing Flow; External Totalizers And Flow Samplers - Siemens SITRANS LUT400 Operating Instructions Manual

Flow

Flow calculation

The SITRANS LUT400 provides numerous open channel flow calculation features
2.15. Flow
(see ).
The device can be configured to select the flow calculation specific to the primary measuring
device (PMD), such as a flume or weir. If the PMD does not match any of the eleven preset
PMD calculations, a universal flow calculation can be used (PMD = Universal Head
Flow Calculation
Flow). See
The SITRANS LUT400 converts the head measurement into flow rate. The flow rate is totalized
and stored in a comprehensive data log to facilitate detailed flow analysis.

Totalizing flow

Totalizing of the calculated flow is ongoing. Daily and running totalizers can be viewed in
Totalizers
. The daily totalizer resets automatically every 24 hours at 23:59:59, and both can be
reset by the user.
In order to adjust the rate of filling of the totalizer, the
an appropriate value. Totalizing that is specific to a time and date can be viewed under View
Logs for flow (see
The SITRANS LUT400 can be programmed to operate a remote totalizer by assigning any of
the relays to act as a totalizer contact. Under this function, the maximum rate of contact
closure is 5/s with a closure duration of 100 ms.

External Totalizers and Flow Samplers

External totalizers are simple counters which count the number of relay clicks produced
by the SITRANS LUT400. This is generally used to keep track of OCM or pumped volume
totals. Note that both of these values are also stored in the SITRANS LUT400 and are
available through communications.
Flow samplers are devices which take a sample of liquid when triggered by a relay click.
These samples are used to monitor water quality over time. Flow samplers can be driven
by OCM volume, pumped volume, or by time depending on the application requirements.
1.
Typically the totalizer should be set for 300 to 3000 counts per day at maximum flow.
A5E33329501
on page 267 for more details.
3.2.6.2. OCM
on page 203).
SITRANS LUT400 (HART) – OPERATING INSTRUCTIONS
2.7.3.3. Totalizer Multiplier
1
2. 1 6.
can be set to
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