Emerson Level-Trol 2500, Инструкция по эксплуатации

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Type 2500
Instruction Manual
Form 1013
December 2005
12
NOTE:
EACH CURVE MARKED WITH PERCENTAGE OF DISPLACER USED.
1C9259 − G
A3891 − 1/IL
Figure 11. Proportional Band and Specific Gravity
Setting Chart (chart assumes standard wall torque tube and
displacer volume in table 2)
1367 High Pressure Instrument Supply System. For
Type 1367 system installation, adjustment, and
maintenance information, see the separate
instruction manual.
Controller/Transmitter Output
Connection
As shown in figure 9, the output pressure connection
is on the back of the controller/transmitter case. After
connecting the output pressure line, turn on the
supply pressure, adjust the filter/regulator to the
appropriate supply pressure required for the
controller/transmitter and check all connections for
leaks.
Prestartup Checks
Adjustments are shown in figure 10 unless otherwise
indicated. Open-loop conditions must exist when
performing the prestartup checks. To obtain
open-loop conditions:
D make sure there is no process flow through the
final control element, or
D disconnect the controller/transmitter output
signal line and connect it to a pressure gauge.
During prestartup, the displacer must be positioned
from its maximum to its minimum range of operation.
Provide a means to change the process variable (the
process level or interface). If the process variable
cannot be varied sufficiently, use the precalibration
procedures in the Calibration section to simulate the
process variable changes required for these checks.
Make sure the RAISE LEVEL dial on the controller is
mounted with the correct side facing out. The dial is
marked on both sides with an arrow. The arrow
points to the left on one side and to the right on the
other. When the sensor is mounted to the left of the
controller/transmitter, the arrow on the raise level
dial should point to the left, as shown in figure 10. If
the sensor is to the right, the arrow should point to
the right. If necessary, remove the two mounting
screws, turn the dial over so the arrow points
correctly, and reinstall the mounting screws. The
level directions shown on the dial will be correct for
both direct-acting and reverse-acting controllers. For
a transmitter, use the same side of the ZERO
ADJUSTMENT dial for both right- and left-hand
sensor mountings.
On a controller or transmitter with an optional
mechanical indicator assembly, the travel indicator
plate is also marked with an arrow on both sides. If
the sensor is to the left of the controller/transmitter,
the arrow on the plate should point to the left. If the
sensor is to the right, the arrow should point to the
right. If necessary, reinstall the plate so that the
arrow points in the correct direction.
Set the PROPORTIONAL BAND control on a Type
2500 or 2500S controller, or the SPECIFIC
GRAVITY control on a Type 2500T transmitter, as
follows:
D Sensor with Both Standard Torque Tube
and Standard Volume Displacer —If the torque
tube is standard and the displacer volume is close to
that listed in table 2, use figure 11 to find the
PROPORTIONAL BAND or SPECIFIC GRAVITY
setting. Locate the specific gravity of the process
fluid on fluid level applications, or the difference
between minimum and maximum specific gravity on
interface level or density applications, on the vertical
axis of the chart. From this location, trace
horizontally to the curve with the desired percentage
of displacer used, then trace vertically up or down to