2 connecting the sensor, 3 connecting the measuring unit, Connecting the sensor – Pyromation Series 642 User Manual
Page 10: Connecting the measuring unit
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Wiring
Series 642
10
Pyromation, Inc.
4.2
Connecting the sensor
4.3
Connecting the measuring unit
NOTICE
Electronic parts may be damaged
► 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, grounding it via
one of the ground screws is recommended.
4.3.1
HART
®
connection
Connection using a transmitter power supply
HART
®
connection with a transmitter power supply
Please refer to Section 4.1 "Quick wiring guide" for the terminal assignment of the sensor
connections.
If the HART
®
communication resistance is not built into the power supply, a 250
Ω
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, specifically HCF LIT 20: “HART, a technical
overview”.