Azbil MVC10A, User Manual

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Azbil Corporation Setting parameters and operating the local data setting device
Model: MVC10A/10F - Multivariable Air Flow Meter 4-19
Leak checking function
This device can determine the air leak rate by measuring the pressure in the piping.
t2
t1
100%
Normal operation
Pressure
Time
Pipe and valve shut.
Compressor stopped.
Setting pressure
of compressor
70%
Compressor start.
80%
To measure the pressure, first start up the compressor as indicated in the above
diagram and measure the time (t
1
) required for the pressure in the piping to reach 80%
of the set value of compressor pressure starting at 70% of the set value. Then, close
the piping system, stop the compressor, and measure the time (t
2
) that elapses from
the time when the piping pressure is at 80% of the set value until it reaches 70% of
the set value, and allow the system to calculate the leak rate by the following:
Leak rate =
Thus, the lower the value, the smaller the leak amount.
(1)
A leak rate is indicated in the operation “Leak Check” - “1 <Leak Rate>.”
< L 1
4
e
3 a k
. 2 5
R a t e >
%
(2) When the measured values (t1, t2, and leak rate) need to be reset, use the process
“Leak Check” - “2 <Reset OK?>.”
(3) Setting of the above-mentioned compressor pressure can be conducted by using
the process “Leak Check” - “3 <Set Press>.” The allowable pressure setting range
is 0.30 to 0.98 MPa.