Function And System Design - Endress+Hauser iTEMP TMT162 Technical Information

Measuring principle
Measuring system
2

Function and system design

Electronic monitoring, conversion and display of input signals in industrial temperature measurement.
1 x RTD/TC /
2 x RTD/TC
Examples of applications
m Two sensors with measuring input (RTD or TC) in remote installation with the advantages: drift alert, sensor backup
function and temperature dependent sensor switch
n 1 x RTD/TC or 2 x RTD/TC as redundancy
o Temperature field transmitter in combination with a sensing element, insert and thermowell as compact thermometer
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The iTEMP temperature field transmitter TMT162 is a two-wire transmitter with analog output or fieldbus
protocol, two (optional) measuring inputs for resistance thermometers and resistance transmitters in 2-wire, 3-
wire or 4-wire connection (for one resistance measuring input), thermocouples and voltage transmitters. The
LC display shows the current measured value digitally and as a bar graph with an indicator for alarms.
Corrosion detection
Corrosion of the sensor connections can lead to corruption of the measured value. The field transmitter offers
the option of detecting corrosion on thermocouples and resistance thermometers with a 4-wire connection
before measured value corruption occurs. The transmitter avoids false measured readings and is also able to
indicate a warning on the display as well as through HART
reasonable values.
Low voltage detection for HART
The low voltage detection prevents the device from continuously outputting an incorrect analog output value
(i.e. due to damaged or incorrect power supply or due to a damaged signal cable). If the required supply voltage
is undershot, the analog output value drops < 3.6 mA for approx. 3 s. An error message appears on the display.
Afterwards the device tries to output the normal analog output value again. If the supply voltage is still too low,
the analog output value drops again to < 3.6 mA.
RTD/TC
RTD/TC
°C
n
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or Fieldbus protocol when wire resistance exceeds
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communication
TMT162
°C
m
°C
o
T09-TMT162ZZ-14-00-xx-yy-002
Endress+Hauser