Rosemount 8712, Справочное руководство

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Reference Manual
00809-0100-4664, Rev BA
January 2010
A-3
Rosemount 8712
Humidity Limits
0–100% RH to 120 °F (49 °C), decreases linearly to 10% RH at 130 °F (54
°C)
Enclosure Rating
Type 4X, IP66
Output Signals
Analog Output Adjustment
(1)
4–20 mA, switch-selectable as internally or externally powered 5 to 24 V
DC; 0 to 1000

load.
Engineering units—lower and upper range values are user-selectable.
Output automatically scaled to provide 4 mA at lower range value and 20
mA at upper range value. Full scale continuously adjustable between -39
and 39 ft/s (-12 to 12 m/sec), 1 ft/s (0.3 m/s) minimum span.
Field Communications, digital flow signal, superimposed on 4–20 mA
signal, available for control system interface. 250

required for Field
Communications.
Scalable Frequency Adjustment
(1)
0-10,000 Hz, switch-selectable as internally or externally powered 5 to 24
V DC, transistor switch closure up to 2 W for frequencies up to 4,000 Hz
and 5 V DC at 0.1 W at maximum frequency of 10,000 Hz. Pulse value can
be set to equal desired volume in selected engineering units. Pulse width
adjustable from 1.5 to 500 msec, below 1.5 msec pulse width
automatically switches to 50% duty cycle. Local operator interface
automatically calculates and displays maximum allowable
output frequency.
Totalizer
Non-volatile totalizer for net, gross, forward and reverse totals.
Optional Digital Output Function (AX option)
Externally powered at 5 to 24 V DC, transistor switch closure up to 3 W to
indicate either:
Reverse Flow:
Activates switch closure output when reverse flow is detected. The reverse
flow rate is displayed.
Zero Flow:
Activates switch closure output when flow goes to 0 ft/s.
Empty Pipe:
Activates switch closure output when an empty pipe condition is detected.
Transmitter Faults:
Activates switch closure output when a transmitter fault is detected.
(1) For transmitters with intrinsically safe outputs, power must be supplied externally.