Azbil KFPA, Руководство пользователя

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Azbil Corporation
22 Model
KFPA
,
KFTA
- Field Mount type Pressure Indicating Controllers
5-2-2: Calibration of reset and rate units
Be extremely careful when handling the reset (rate) restriction. Even a minor damage
to the needle or valve seat can cause a great change in the characteristics. So, the reset
restriction and the dial base are firmly fixed. When the unit has been disassembled for
servicing, calibrate it observing the following procedures:
Reset unit
(1) Set the set point pointer (SP) at 50% F.S.
(2) Set the proportional band dial at 100 (% P.B.) of direct action. In this case, fully
open (0.05 min. or less) the reset restriction and, if the rate unit is provided, fully
open (0.05 min. or less) the rate restriction also.
(3) By adjusting the PV value, balance the controller output (control output pressure)
at 46.7 kPa {350 mmHg}.
(4) Fully close the reset restriction (30 min. or more).
(5) By adjusting the PV value, set the controller output at 53.3 kPa {400 mmHg}.
(6) See the reset dial at 2 min.
(7) Measure the time required by the controller output to change from 53.3 to 60 kPa
{400 to 450 mmHg}.
(8) Make sure that the measured time is not longer than 120 + 60 sec.
(9) Adjust the position of the reset unit dial after loosening its two set-screws, as
required.
Rate unit
(1) Set the set point pointer (SP) at 50% F.S.
(2) Set the proportional band dial scale at 100 (% P.B.) of direct action. In this case,
fully open (0.05 min. or less) the rate restriction and, if the reset unit is provided,
fully open (0.05 min. or less) the reset restriction also.
(3) By adjusting the PV value, set the controller output at 40 kPa {300 mmHg}.
(4) Fully close the reset and rate dials (30 min. or more).
(5) By adjusting the PV value, set the controller output at 80 kPa {600 mmHg}.
(Denote this value by n
1
.)
(6) Fully open the rate dial (0.05 mm or less), measure the residual pressure (denote
this value by n
2
) and calculate the rate amplitude.
Rate amplitude
(7) Repeating the procedure of (2) to (5) so that the controller output becomes 80 kPa
{600 mmHg}.
(8) Rapidly change the rate dial to 2 min. and measure the time t in which the output
change to 63.2% of the value of n
1
- n
2
.
(9) Make sure that t
×
W is not longer than 120 + 60 sec.
W
n
1
n
2
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