Azbil KFDB, Руководство пользователя

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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.
(c) Clean metal parts with approved solvent such as petroleum naphtha or Clorothene.
Depress the valve stem (2) against the conical spring (5) to allow the solvent to penetrate
through the seat which is hit by the port section of the valve stem.
(d) Examine the inner exhaust ring (3) and value stem (2). If dirty, clean them wit a cloth. Do
not use any solvent to clean them.
(e) Dry all parts thoroughly with clean compressed air.
(f) Replace diaphragms (16) and (11) if worn or damaged.
(g) Reassemble the pilot relay by rejoining all parts in order with assembly screws (1), and
nuts (19). Tighten the screws evenly.
7-4. Removal of AUTO Unit When in MAN Mode
(1) Balance the instrument and then transfer it to the MAN mode. (See Section 3-3.)
(2) Apply a deviation in the direction that the AUTO output is decreased. (Turn the SP knob
so that SP is smaller than PV when in the reverse action or SP is greater than PV when in
the direct action.)
(3) Set the proportional band of the controller to the minimum (PV not greater than 5 %).
(4) Press the CHECK button of the manual loader and check that the AUTO output is zero.
(5) Remove the automatic controller units (controller unit, integral unit, and derivative unit).
When this is done, the manual loading pressure will be decreased slightly (within 3 %FS).
Re-adjust the manual loading pressure as required.
(6) When the SP is of a remote setting type (cascade type) and cannot be varied, proceed as
follows instead of the procedure of (2) and (3).
(a) Remove the element of the link. Make the AUTO output zero by moving the PV
pointer.
(b) Make the nozzle back pressure zero by moving the flapper away from the nozzle of the
controller.
7-5. Maintenance of Batch Switch
Periodically clean the exhaust port with a needle wire of 0.8 mm diameter. The circuit board
of the batch unit can be removed by removing its two clamping-screws. The exhaust port is
located in the groove in the center on the back side of the batch switch unit.