User`s manual

<7. Operation>
7-4
IM 01C25B01-01E
(2) WhenyoucannotobtaintheLowRange
Value from the actual measured value of
0%;
Adjust the transmitter output to the actual measured
value obtained by a digital manometer or a glass
gauge.
[Example]
The measuring range of 50 to 250 kPa; the actual
measured value of 130 kPa.
130–50
250–50
Actual measured value=
x100=40.0%
(=10.4mA)
Turn the screw to match the output signal to the
actual measured value.
7.3 Starting Operation
After completing the zero point adjustment, follow
the procedures below to start operation. Steps
1)and2)arespecictothedifferentialpressure
transmitters.
1) Closetheequalizingvalve.
2) Gradually open the low pressure stop valve.
This places the transmitter in an operational
condition.
3) Conrmtheoperatingstatus.Iftheoutput
signalexhibitswideuctuations(hunting)dueto
periodic variation in the process pressure, use
the communicator to dampen the transmitter
outputsignal.Conrmthehuntingusinga
receiving instrument or the integral indicator,
and set the optimum damping time constant.
4) Afterconrmingtheoperatingstatus,perform
the following.
IMPORTANT
• Removethecommunicatorfromtheterminal
box,andconrmthatnoneoftheterminal
screws are loose.
• Closetheterminalboxcoverandthe
ampliercover.Screweachcoverintightly
until it will not turn further.
• Therearetwocoversthatmustbelocked
on the ATEX Flameproof type transmitters.
An Allen head bolt (shrouding bolt) under
the edge of each cover is used to lock the
cover. When the shrouding bolt is driven
counterclockwise with an Allen wrench, the
bolt rotates upward and locks the cover. (See
section8.4.)Afterlockingthecovers,conrm
that they are secure and cannot be opened
by hand.
Tighten the zero-adjustment cover mounting
screw to secure the cover.
• Tightenthezero-adjustmentcovermounting
screw to secure the cover.
7.4 Shutting Down the
Transmitter
Shut down the transmitter as follows.
Steps2)and3)arespecictothedifferential
pressure transmitters.
1) Turn off the power.
2) Close the low pressure stop valve.
3)Opentheequalizingvalve.
4) Close the high pressure stop valve.
5) Close the high pressure and low pressure tap
valves.
NOTE
• Whenevershuttingdownthetransmitterfora
longperiod,removeanyprocessuidthatis
in the transmitter pressure-detector section.
• TheequalizingvalvemustbeleftOPEN.