ABB Platinum standard Series, Инструкция по эксплуатации

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OPERATING PROCEDURES
CONFIGURATION PROCEDURE
WBPEEUI110504A0 5 - 3
Primary Engineering Units
Primary engineering units are programmable. The selections
appearing on the Type STT terminal display are:
•
iH20 — inches of water.
•
mmHG — millimeters of mercury.
•
cmH20 — centimeters of water.
•
PSI — pounds per square inch.
•
MPA — megapascals.
•
kPA — kilopascals.
•
BARS — bars.
•
mBARS — millibars.
•
Kgcm2 — kilograms per square centimeter.
Primary Upper and Lower Range Values
The range of the transmitter may be set electronically to any
value within ±100 percent of the upper range limit to suit a
specific application, provided the values are acceptable to the
transmitter (refer to Table
1-2 for the nominal and minimum
ranges of the transmitters).
Startup and Failure Conditions
On power up, there is a four-second initialization period dur-
ing which the output of the transmitter is in transition from
nonpowered (no current output) and an output of either above
100 percent or below zero percent as defined during
configuration.
If in the analog mode, INITIALIZE LOW sets the output to below
zero percent (approximately 3.7 milliamperes) while INITIALIZE
HIGH sets the output to above 100 percent (approximately
22 milliamperes).
If in the digital mode, INITIALIZE LOW sets the output to below
zero percent (approximately 3.7 milliamperes) while INITIALIZE
HIGH sets the output to above 100 percent. However, the cur-
rent stays at approximately 3.7 milliamperes. The default ini-
tialization value is low (below zero percent). After initialization,
the output ramps up or down to the correct value.
If during its continual diagnostics the microcomputer detects
an error that is fatal to the transmitter or system, the trans-
mitter output goes to a predetermined fail level. This level
must be selected during configuration. The default value is low
WARNING
The outputs of smart devices change to a fixed value during
initialization and detected failure conditions. These values
must be selected by the user to ensure safe operation.