Emerson Fisher 2500, Инструкция по эксплуатации

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Instruction Manual
D200124X012
2500 and 2503 Controllers/Transmitters
June 2017
25
13. If the flexure strip base has been moved as far as possible and the output pressure span is still too large or too small,
slightly adjust the PROPORTIONAL BAND or SPECIFIC GRAVITY adjustment as follows:
D
If the output pressure span is too large, slightly increase the PROPORTIONAL BAND or SPECIFIC GRAVITY setting.
D
If the output pressure span is too small, slightly decrease the PROPORTIONAL BAND or SPECIFIC GRAVITY setting.
14. Repeat the procedure from step 4 until the required calibration points are obtained.
Note
If you cannot calibrate the controller or transmitter, look for other problems as described in the Troubleshooting procedures, such
as leaking connections, or a binding displacer rod. If none of these troubles are apparent, ensure that the displacer is sized
correctly for the application.
2500S and 2503 Controllers
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 adjustment (2500S only) is at the setting determined according to the
appropriate prestartup check procedure.
3. Perform one or the other of the following:
D
For direct acting controllers , set the RAISE LEVEL adjustment between 1.0 and 1.5.
D
For reverse acting controllers, set the RAISE LEVEL adjustment between 3.5 and 4.0.
4. Set the process variable at 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. Be sure the flapper is centered over the nozzle. If not, loosen the hex nut (key 40, figure 16) and reposition the
flapper, tighten the hex nut.
6. Adjust the flapper (key 32, figure 16) as described 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).
D
For Direct Acting Controllers, move the flapper toward the nozzle until the output pressure switches to full supply
pressure, then carefully adjust the flapper away from the nozzle until the output pressure switches to 0 bar (0 psig).
D
For Reverse Acting Controllers , move the flapper away from the nozzle until the output pressure switches to 0 bar (0
psig), then carefully adjust the flapper toward the nozzle until the output pressure switches to full supply pressure.