<2. General>
2-1
IM 02C01B04-01EN
2. General
2.1 Outline
Model Y/11GM Pressure Transmitter is a force-
balance instrument that measures pressure and
transmits it as a proportional 0.2 to 1.0 kgf/cm
2
or
bar, 20 to 100 kPa, or 3 to 15 psi pneumatic signal.
F0201.ai
Figure 2.1
Outline
2.2 Principle of Operation
The pressure being measured is applied to a
bellows capsule. The force on the capsule is
transmitted through a flexure to the lower end of
the force bar. The metal diaphragm seal serves as
both a fulcrum for the force bar and as a seal for the
pressure chamber. The force is transmitted through
the flexure connector to the range bar which pivots
on the range wheel.
Any movement of the range bar causes a minute
change in the clearance between the flapper and
nozzle. This produces a change in the output
pressure from the amplifier to the feedback bellows
until the force on the feedback bellows balances the
force on the bellows capsule.
The output pressure which is established by this
force balance is the transmitted signal and is
proportional to the pressure applied to the bellows
capsule. This signal is transmitted to a pneumatic
receiver to record, indicate and/or control.
F0202.ai
Reducing tube
Air supply
Pneumatic
Amplifier
Range wheel
Output
Range bar
Feedback
bellows
Zero
adjustment
screw
Flexure
Bellows
capsule
Pressure
connection
Diaphragm seal
Force bar
Flexure connector
Flapper nozzle
assembly
Figure 2.2 Principle of Operation
