Fujimoto Fuji Differential Pressure Transmitter FKK 4 - Manual (Page 39)

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3.2 Span adjustment (Change Upper Range Value)
The measuring range for each transmitter is determined according to its type.
The span is changed by the external adj. screw when the mode setting switch is set at “1” or ”6"
position.
(1) Set the mode setting switch to “1” or ”6” position.
(2) Apply standard input pressure corresponding to new Upper Range Value.
(3) Adjust output to 20.00mA by turning the external adj. screw.
Decrease
Increase
(4) Then, apply input pressure corresponding to new Lower Range Value again and make sure
output is 4mA.
(5) After span adjustment according to above procedure from 3.2-(1) to (4), please set mode
setting switch to appropriate position
4. Damping adjustment
If a pulsation of the output current is caused due to flow noise etc., it can be attenuated by performing
damping adjustment.
Damping is adjustable in 8 steps. The damping constant becomes lager in the order of 0,1,2,3and 4.
These damping constant correspond to time constant 0, 0.3, 0.6, 1.2, 2.4, 4.8, 9.6, 19.2 seconds for the
transmission unit regardless of span.
The relationship between position of switch and time constant are indicated in table 2.
Note)
The damping constant above is a time constant applied to the transmission unit only. The
detecting unit has additional time constant
(Please see data sheet about details)
Important
After adjustment, the transmitter should be kept energized at about 10 seconds to write
the adjustment parameter into memory.
Important
When the transmitter respose speed is changed, the time constant of the control system
is also changed. Be sure to check the controllability again.
5. Fixed current output and its adjustment
Output of fixed current regardless of input is available.
Output of fixed current is convenient for loop check.
When the output(4 or 20mA)is in error, it can be adjusted by the external adjustment screw.