Emerson Fisher 2500, Instruction Manual

Page: 23 / 40

Instruction Manual
D200124X012
2500 and 2503 Controllers/Transmitters
June 2017
23
Figure 10 shows adjustment locations, except as otherwise indicated. In order to calibrate, open‐loop conditions must
exist. One way to obtain an open loop is to ensure that there is no flow through the final control element. Another way
to obtain an open loop is to disconnect the controller/transmitter output signal line and plug the output connection
with a test pressure gauge.
Several steps in these calibrating procedures require setting the process variable at its minimum and maximum limits,
according to table 6.
Note
If the process cannot be varied readily or the Wet Calibration method cannot be used in the following steps, be sure to use the
proper sequence of correct weights as found in the Determining Amount of Suspended Weight procedure. Whenever the
following steps require particular prestartup checks, refer to the appropriate procedures for: 2500 Controller or 2500T
Transmitter, 2500S Controller, or 2503 Controller.
2500 Controller and 2500T Transmitter
1. Turn on the supply pressure and check that it is set according to the appropriate prestartup checks procedure.
2. Make sure that the PROPORTIONAL BAND or SPECIFIC GRAVITY adjustment is at the setting determined according
to the appropriate prestartup check procedure.
3. Adjust the RAISE LEVEL (2500) or ZERO ADJUSTMENT (2500T) to the appropriate value per table 5. This table gives
recommended settings based on maximum and minimum possible PROPORTIONAL BAND (2500) or SPECIFIC
GRAVITY (2500T) settings. If an intermediate PROPORTIONAL BAND or SPECIFIC GRAVITY setting is necessary,
extrapolation may be used to determine a new RAISE LEVEL or SPECIFIC GRAVITY setting.
Table 5. Recommended Settings For Pre‐Startup Checks
MOUNTING ACTION
RECOMMENDED RAISE LEVEL SETTING
FOR 2500 CONTROLLER
RECOMMENDED ZERO ADJUSTMENT SETTING FOR 2500T
TRANSMITTER
For Predetermined
PROPORTIONAL BAND Dial
Setting of 10
(1)
For Predetermined
PROPORTIONAL BAND Dial
Setting of 0
(1)
For Predetermined
SPECIFIC GRAVITY Dial
Setting of 1.0
(1)
For Predetermined
SPECIFIC GRAVITY Dial
Setting of 0
(1)
Right‐hand
Direct 3.0 to 3.5 4.0 to 4.5 1.5 to 2.0 to right 0.5 to 1.0 to right
Reverse 6.5 to 7.0 0.5 to 1.0 1.5 to 2.0 to left 4.0 to 4.5 to right
Left‐hand
Direct 3.0 to 3.5 4.0 to 4.5 1.5 to 2.0 to left 0.5 to 1.0 to left
Reverse 6.5 to 7.0 0.5 to 1.0 1.5 to 2.0 to right 4.0 to 4.5 to left
1. For proportional band dial settings between 10 and 0 or for specific gravity dial settings between 1.0 and 0, interpolate the value.
4. Set the process variable to the minimum value of the input range as shown in table 6. For constructions with an
indicator assembly, make sure that the pointer is over the LOW mark.
Note
In the following step, the alignment screw (key 33, figure 16) must always remain screwed in far enough to provide spring tension
on the underside of the alignment screw head.
5. Adjust the flapper (key 32, figure 16) to obtain the appropriate pressure listed below. For coarse flapper
adjustment, loosen the hex nut (key 40, figure 16) and rotate the flapper assembly about the torque tube shaft. For
fine flapper adjustment, turn the flapper alignment screw (key 33, figure 16).