Temperature Sensor - Siemens SITRANS L 7ML5400 Operating Instructions Manual

Note
The SITRANS LUT400 supports several different transducers. Some, like the XPS-30, are driven
by a low power level, while others, like the XPS-15, are driven by a high power level. It may
be possible to damage a lower power transducer like the XPS-30 if the transducer selection is
currently set to one of the high power transducers. Follow the steps below to avoid this
possibility:
1. Set the transducer selection to No Transducer before powering down the LUT400.
2. Connect the new transducer.
3. Power up the LUT400 and select the correct transducer. This way, the transducer will not
be driven with the wrong power level, even for the short period of time until the correct
selection is made.
5.1.5

Temperature sensor

The speed of sound changes as temperature changes. To ensure accurate level measurement,
the SITRANS LUT400 compensates via an external temperature input. All Siemens EchoMax
transducers have an internal temperature sensor for this purpose, and for the fastest
temperature response, Siemens also offers a dedicated temperature sensor, the TS-3.
If the following conditions apply, a separate TS-3 temperature sensor will ensure optimum
accuracy:
• The transducer is exposed to direct sunlight (or other radiant heat source).
• The temperature of the atmosphere between the transducer face and monitored surface
differs from the temperature of the transducer.
• Faster response to temperature changes is required.
SITRANS LUT400
Operating Instructions, 04/2021, A5E33329501-AG
Connecting
5.1 Connecting SITRANS LUT400
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