Connecting The Measuring Unit - Endress+Hauser iTEMP HART TMT142 Manuel De Mise En Service

Wiring
"
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56
4.3

Connecting the measuring unit

Caution!
• Switch off power supply before installing or connecting the device. Failure to observe this may
result in destruction of parts of the electronics.
• If the device has not been grounded as a result of the housing being installed, we recommended
grounding it via one of the ground screws.
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4.3.1 HART connection
Note!
communication resistance is not built into the power supply then a 250 Ω
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If the HART
communication resistor must be fitted into the 2-wire supply lines.
For connection hints, please take special notice of the documentation supplied by the HART
Communication Foundation, specially HCF LIT 20: "HART, a technical overview".
Connection using the E+H power supply RN 221N
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Fig. 6: HART connection with the E+H power supply RN 221N
Connection using other power supplies
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Fig. 7: HART connection using other power supplies
TMT142
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Endress+Hauser