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OM2-6220-0000 Field Mounted Indicating Controller Model KFDB/KFKB/KFLB User’s Manual...
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In no event shall Azbil Corporation be liable to anyone for any indirect, special or consequential damages. This information and specifications in this document are subject to change without notice.
Chapter 1. GENERAL 1-1. Description The KF Series Field Mounted Indicating Controller detects and indicates a process variable (flow, pressure, liquid level, etc.), and transmits and indicates a pneumatic control signal (20 to 100 kPa {0.2 to 1.0 kgf/cm }) by comparing the detected value with the setpoint value. The setpoint is adjustable locally (manually) with the setting control on the front panel or inside of the instrument or remotely (in a cascade system) with an external pneumatic signal.
1-3. Detectors (Meter Bodies) Process Operator’s Range or Type Model No. Variable Manual Differential High or medium differential pressure KFDB11/22 OM2-5220-1100 pressure Low differential pressure KFDB33 Very low differential pressure KFDB44 Flange type KFDB61/62 Remote sealed type KFDB71/72 High working pressure type KFDB81/82 Pressure High pressure...
1-4. Specifications Specifications of Controller (Main Unit) (1) Performance Accuracy: ±1 %FS Repeatability: 0.3 %FS or better Dead Band: 0.2 %FS or less (2) Indicator Section Indicating Angle: 44 deg Scale Length: 150 mm Pointers: PV (red), SP (green) Output Pressure Gauge: Scale 0 to 200 kPa {0 to 2 kgf/cm (3) Setting Section Local Setting: With setting control on front panel or inside of case.
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Color: Dark beige (Munsell 10YR4.7/0.5) Installation: Pressure Model (KFKB): 2-inch pipe stanchion or panel flush mount Differential Pressure Model (KFDB): 2-inch pipe stanchion, panel flush mount, or direct mount on process Liquid Level Model (KFLB): Direct mount on process...
1-5. Transmitter Section The mechanical displacement detected by the detector section is converted into torque which is conveyed via the seal tube (torque rod) to the input beam to drive the flapper which dictates the nozzle back pressure which is amplified by the pilot relay in order to be delivered as pneumatic output signal.
Fig. 1-4 (a). Involute Curve Section Fig. 1-4. Fig. 1-4 (b). Dash pot Assembly Condition (Torque Tube Type KFLB) 1-6. Indicating Controller Section 1-6-1. General The pneumatic output pressure of the transmitter section, which represents the process being measured, is applied to the pneumatic pressure signal receiver unit, thereby causing displacement of the end of the element.
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Fig. 1-5. Deviation Generating Mechanism 1-6-3. Controller Mechanism The controller mechanism is comprised of a proportional unit, an integral unit and/ or a derivative unit. The various combinations of these controller units are possible and interchangeable to best suit the characteristics of the process to be controlled. (1) Proportional (P) Unit This unit is comprised of a nozzle-flapper mechanism and a feedback mechanism (a feedback chamber and a reset chamber).
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Fig. 1-6. Controller Mechanism (2) Integral Unit and Derivative Unit The pressure of the feedback chamber of the proportional unit is fed to the integral (reset) chamber of the proportional unit via the restriction and capacity chamber of the integral unit in order to provide an integral (I) action.
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(3) Other Controller Units a) ON/OFF Unit This unit is used for control of process whose time constant is large but dead time is small. This unit is structured by eliminating the feedback mechanism from the proportional control unit so that the nozzle back pressure is directly applied to the pilot relay.
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(a) Proportional + Manual Reset (b) ON/OFF Action (c) Differential Gap Action Fig. 1-9. Operating Principles 1-6-4. Manual Loader Unit This unit is comprised of a pressure regulator for manual loading pressure setting, an AUTO/ MAN transfer lever, a check switch, etc. When in the AUTO mode (the transfer lever set in the A position), the controller output gauge indicates the automatic control output pressure of the controller.
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1-6-5. Pneumatic Pressure Signal Receiver Unit This unit operates either in a direct (local) made or in a remote (cascade) mode. In the former case, this unit receives the pneumatic output signal (20 to 100 kPa {0.2 to 1.0 kgf/cm }) of the transmitter section and converts it into mechanical displacement which is fed via the overtravel link to the deviation generating mechanism in order to be magnified to drive the...
Chapter 2. INSTALLATION The installation method differs as the controllers are used in conjunction with the various types of detectors. For the installation and process connection methods, refer to the operator’s manuals of respective detectors. This section describes primarily the pneumatic piping method for the controller.
Chapter 3. OPERATION METHOD This section covers the operation method of the controller. For the detector which is used in conjunction with the controller, refer to the operator’s manual of the detector itself. 3-1. Preparation Check the air piping for that they are correctly connected and there is no leak. 3-2.
(6) In the AUTO mode of operation, select appropriate PID values to suit the process. (7) To transfer from the AUTO mode to the MAN mode, press the check button with the switch set in the A position in order to read the manual output. Adjust the MAN output to the AUTO output by means of the pressure regulator and confirm that the output pressure gauge does not change even when the check button is pressed, and then change the lever from the A position to the M position.
Chapter 4. CALIBRATION AND ADJUSTMENT OF TRANSMITTER SECTION 4-1. General The detector section (meter body section) generates with its torque tube a torque which is proportional to the measured process variable. The generated torque is conveyed to the transmitting mechanism of the transmitter. Therefore, regardless of the type of the detector used in conjunction, the transmitter section should be adjusted so that it transmits a linear output of 20 to 100 kPa {0.2 to 1.0 kgf/cm } for 1 to 100 % of the measuring range.
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Fig. 4-1. Transmitter Section (7) Apply to the high pressure connection port a pressure corresponding to 100 % of the measuring range. (8) If the output pressure is shifted from 100 %, adjust the SPAN ADJ boss at the bottom of the feedback bellows as follows: If the output is higher than 100 %, turn the boss so that the output becomes lower than 100 % by an amount of 1/4 of the shift.
4-3. Calibration of Gauge Pressure Transmitter (1) Connect to the process pressure connection port of the meter body a variable pressure source (such as the air supply via a regulator) corresponding to the measuring range and a precision pressure gauge covering the measuring range. (For a flange type meter body, prepare a piping adaptor.) (2) Apply to the process pressure connection port a pressure corresponding to 100 % of the measuring range by adjusting the variable pressure source.
4-5. Calibration of Liquid Level Transmitter (KFLB _ _ -61/62) (1) Fix the torque tube assembly together with the transmitter to a bench by using, for example, a vice as shown in Fig. 4-2. Note: Exercise care so that no unreasonably large torque is applied to the torque tube. Fig.
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(2) Adjust so that the total weight (W) becomes the same with the weight of the float (3 kg for medium specific-gravity measurement or 4.5 kg for low specific-gravity measurement). (W = Calibration weight + Pan weight + Dummy weight) (3) Apply to the pan a weight corresponding to 100 % of the measuring range.
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4-5-3. Calibration procedure for Specific-gravity Transmission (1) This procedure is identical with that for liquid level transmission, except that the following formulas should be used. (a) Total weight W including the two weights, pan and others: W = (Weight of float) − π ·D ·L·ρ...
Chapter 5. CALIBRATION AND ADJUSTMENT OF DEVIATION GENERATING MECHANISM Align together the PV pointer and SP pointer as described in the following: Fig. 5-1. Deviation Generating Mechanism (1) Set the PV pointer of approximately 50 % on the scale either by removing the link which runs from the receiver unit or by making the PV input approximately 50 %.
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(c) Set the integral mechanism to the full open state (the minimum integral time). Move the SP pointer so that the output air pressure becomes 50 %FS (59.1 kPa {443 mmHg}). (d) After the output air pressure is stabilized, set the reset mechanism to the fully closed state (the maximum integral time) and align the two pointers together at 50 %FS.
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(f) Set the integral dial (reset dial) scale at 2 minutes. (g) Count the time the controller output takes to change from 53.3 kPa {400 mmHg} to 60 kPa {450 mmHg}. (h) Check that the counted time is within 120±60 seconds. (i) As required, shift the position of the dial of the integral unit and fix it in the new position.
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5-1-3. Other Calibration and Adjustment (A) ON/OFF Controller Before starting adjustment, check zero deviation as follows: (a) Set the setpoint at 50 %. (b) Remove the travel link (PV) of the indicating mechanism side and insert the adjustment pin. (c) Check that the PV pointer and the SP pointer are accurately aligned together. If there is any shift, correct is by means of the SP pointer adjustment pin.
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(B) Differential Gap Controller Before starting adjustment, check zero deviation as follows: (a) Set the setpoint at 50 %. (b) Remove the travel link (PV) on the indicating mechanism side and insert the adjustment pin. (c) Check that the PV pointer and the SP pointer are accurately aligned together without any shift.
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Set the differential gap (DIFF GAP) dial to the clockwise or counterclockwise 100 % position. Adjust the feedback link adjustment pin so that the output increases at the setpoint position. (To lower the output once, open slightly the flapper with the tip of a screwdriver.) Repeat the procedure of (4), (5) and (6) so that the output rise position is within setpoint (SP) ±1.5 %FS at any point within the total range of the differential gap...
Chapter 6. ADJUSTMENT OF INDICATING SECTION Adjustment of the indicating section should be made after that for the deviation generating mechanism and controller mechanism is complete. The structure of the PV indicating mechanism and that of the SP indicating mechanism for the cascade mode of operation are identical.
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(3) Linearity Adjustment (a) For linearity adjustment, use the 50 % point of the scale. (b) If an error greater than 1 %FS is found, vary the travel link length by turning the adjustment knob. If the error is in the positive side of the scale, shorten the travel link (turn the knob counterclockwise as viewed from the instrument bottom).
Chapter 7. MAINTENANCE Fig. 7-1. Points To Be Serviced For Maintenance 7-1. Periodical Inspection (1) Check the air pipes and joints for leak. (2) Check the air supply line drain, filter, compressor, air cleaner/drier, and tanks. (3) Check the instrument filters and restrictions for stains. Replace the stained filters. Clean the dirty restrictions using a needle wire of 0.12 mm diameter.
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Fig. 7-2. Maintenance of Controller Unit...
7-3. Pilot Relay Name Quantity SCREW VALVE STEM HOUSING GUIDE PIN CONICAL SPRING WASHER SPRING NOZZLE WASHER SEAL DIAPHRAGM (LOWER) EXHAUST RING (OUTER) EXHAUST RING (INNER) AREA PLATE WASHER DIAPHRAGM (UPPER) COVER Fig. 7-3. Pilot Relay Assembly...
Remove the pilot relay as described in 1 above, service it as described below, and then install it in the original position. (a) Remove the three assembly screws (1) and nuts (19). (See Figure 5.) (b) Parts (3) to (17) will separate in order. It is not necessary to separate parts (2) to (6) unless they are to be replaced.
7-6. Troubleshooting Symptoms of troubles, probable causes, and remedies are shown in the following table. For adjustments, refer to the preceding section. Symptom Probable cause Remedy Pilot relay whines. Stained valve stem (section hitting the port) Take out pilot relay and clean the valve stem (section hitting the port) No or only very low No air supply is provided or air supply...
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Warranty period and warranty scope 1.1 Warranty period Azbil Corporation’s products shall be warranted for one (1) year from the date of your purchase of the said products or the delivery of the said products to a place designated by you.
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Although acceleration of the above situation varies depending on the conditions or environment of use of the products, you are required not to use any Azbil Corporation’s products for a period exceeding ten (10) years unless otherwise stated in specifications or instruction manuals.
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