ABB Platinum standard Series, Инструкция по эксплуатации

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DESCRIPTION AND OPERATION
FUNCTIONAL OPERATION
WBPEEUI110504A0 2 - 7
Diagnostics
Continuous self-diagnostics are accessible on demand through
the Type STT terminal. Areas monitored include: cell; cell tem-
perature; electronics temperature; dynamic temperature; cali-
bration; configured pressure limits; input circuits; analog to
digital converter; microcontroller ROM, SEEPROM, and
EEPROM; and reference voltages. Diagnostics identify the mal-
functioning section of the transmitter. The diagnostics may
indicate if a calibration error occurs.
Software Functions
Configuration and operational commands allow the input of an
ID tag for the transmitter configuration, selection of engineer-
ing units (primary and secondary), and definition of the out-
put. The output can be a linear, square root,
-power or
-
power representation of the input.
-power and -power apply to open channel measurements
to find flow rates through flumes and weirs in processes such
as water delivery and treatment.
-power is used for flumes,
while -power is used for weirs. Take the measurements in
these situations using a bubbler system or a stilling chamber.
Other calculated outputs include volume of a spherical or hor-
izontal flat end cylindrical tank or a function generator that
follows a curve consisting of six straight line segments. The
output can be set for normal or reverse acting and fixed to a
specific value for plant startup and troubleshooting purposes.
Other commands allow the output to be set to default values
upon transmitter power up and failure. The Type STT terminal
also supports configuration, input, output, and transmitter
status monitoring. A damping adjustment command is also
available.
SPHERICAL TANK VOLUME CALCULATION
Figure 2-7 shows a spherical tank setup. This is a common
industrial tank. This procedure shows how to calculate the
values entered into the transmitter (via the Type STT terminal)
during configuration if
VOL./SPHERE is chosen from the OUT-
PUT TYPE menu.
1. The empty tank pressure is the primary lower range value.
a. If the location of the cell is at the bottom of the sphere,
then the primary lower range value is 0.00 kilopascals
(0.00 inches of water).
b. If the location of the cell is below the bottom of the
sphere, as shown in Figure
2-7 , then offset the zero by set-
ting the primary lower range value to the pressure
3
2
⁄
5
2
⁄
3
2
⁄
5
2
⁄
3
2
⁄
5
2
⁄