Rosemount 8750WA, Quick Installation Manual

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Quick Installation Guide
00825-0100-4750, Rev BA
June 2009
Rosemount 8750WA
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Connect 4–20 mA Loop External Power Source
The 4–20 mA output loop signal may be powered internally or externally. The default
position of the internal/external analog power jumper is in the
internal position. The
user-selectable power supply jumper is located on the electronics board.
Internal
The 4–20 mA analog power loop may be powered from the transmitter itself. Resistance in
the loop must be 600 ohms or less. If a HART Field Communicator or control system will be
used, it must be connected across a minimum of 250 ohms resistance in the loop.
External
HART multidrop installations require a 10–30 V DC external analog power source. If a HART
Field Communicator or control system is to be used, it must be connected across a
minimum of 250 ohms resistance in the loop.
To connect external power to the 4–20 mA loop, connect -DC to Terminal 1 and +DC to
Terminal 2.
NOTE
To connect any of the other output options (pulse output and/or digital input/output), consult
the comprehensive product manual.
8750WA12 Wiring Instructions
Wire the transmitter according to local electrical requirements. Ground the transmitter cage
via the threaded conduit connection. For ac power applications, connect ac Neutral to
terminal N and connect ac Line to terminal L1. For dc power applications, properly connect
the positive and negative terminals. Units powered by 12-42 V dc power supply may draw
up to 1 amp of current. In addition, follow the supply wire and disconnect requirements
below:
Figure 13. Transmitter Power Connections
4750RevBAQIG.fm Page 17 Thursday, July 16, 2009 3:52 PM