Rosemount 8732E, Быстрое руководство по установке

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Quick Installation Guide
00825-0100-4662, Rev CB
July 2011
Rosemount 8732
16
Supply Wire Requirements
Use 14 to 18 AWG wire rated for the proper temperature of the application. For connections
in ambient temperatures above 140 °F (60 °C), use a wire rated for 176 °F (80 °C). For
ambients greater than 176 °F (80 °C), use a wire rated for 230 °F (110 °C). For DC powered
transmitters with extended power cable lengths, verify that there is a minimum of 12 V DC at
the terminals of the transmitter.
Disconnects
Connect the device through an external disconnect or circuit breaker. Clearly label the
disconnect or circuit breaker and locate it near the transmitter and per local electrical
control.
Overcurrent Protection
The Rosemount 8732 Flowmeter Transmitter requires overcurrent protection of the supply
lines. Maximum ratings of overcurrent devices are as follows:
Connect 4–20 mA Loop External Power Source
For transmitters with non-I.S. Output, 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
Figure 13. Power Supply Current
Table 6. Overcurrent Ratings
Power System Fuse Rating Manufacturer
95-250 V AC 250 V; 2 Amp, Quick Acting Bussman AGCI or Equivalent
42 V DC 50 V, 3 Amp, Quick Acting Bussman AGCI or Equivalent
12 18 24 30 36 42
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
Power Supply (Volts)
I = 10/V
I = Supply current requirement (Amps)
V = Power supply voltage (Volts)
Supply Current (Amp
s
)
4662RevCBQIG.fm Page 16 Wednesday, July 6, 2011 3:41 PM