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Installation
Avoid mounting this device in the following locations:
• Locations whose ambient temperature falls below −15˚C and rises above +60˚C
• Locations whose ambient humidity exceeds 90 %RH
• Locations subject to sudden changes in temperature and condensation
• Locations be filled with corrosive gases and flammable gases
• Locations where there are lots of conductive substances (e.g. dust, salt or iron
dust), or organic solvents
• Locations subject to vibration or shock
• Locations subject to splashing by fluids (e.g. oil, chemicals.)
• Locations where strong magnetic or electrical fields are generated
Handling precautions
•
Although this device can be installed outdoors, if it is installed at the locations
subject to direct sunlight, be sure to provide a sunshade.
Doing so might cause faulty operation.
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Behavior when the flowrate greatly exceeds the upper limit of flowrate
If the actual velocity exceeds the maximum measurable velocity of 36 m/s, the flow-
rate display will stop increasing in proportion to the flowrate. Be sure to use this
device within the maximum measurable velocity.
If the velocity exceeds 50 m/s, the flowrate display will begin to decrease, giving the
appearance that the flowrate is within the flowrate range limits.
Also, if there is a sudden greatly excessive velocity (50 m/s or more) for a very short
period, the flowrate display will continue to indicate flow within the flowrate range,
without indicating the spike.
Especially when this device is used for flow control, make sure to take appropriate
measures, such as controlling the supply pressure or using a throttle valve, so that
even at maximum control output, the flowrate does not exceed 36 m/s.
Actual velocity
50 m/s
Measurable
velocity range
36 m/s
Upper limit
Fl
ow
ra
te d
is
pl
ay
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Precautions for piping installation
• When this device is installed, be sure to provide the bypass piping as shown below.
Also, for the valves before and after this device, use a ball valve like as having the
structure which does not disturb the gas flow.
Bypass piping valve
Upstream side valve
Downstream side valve
MVF
Chapter 3. INSTALLATION, MOUNTING, WIRING
7
