Definition And Terminology - SMC Networks PF2D5 Series Operation Manual

■Definition and terminology

Terms
A
Analogue output
C
Cavitation
F Fluid temperature
F.S.
(Full span, Full scale)
K
Karman vortex
O
Operating humidity
range
Operating
temperature range
P
Part in contact with
fluid
Pressure
characteristics
Proof pressure
Rated flow range
R
Rated pressure range
Repeatability
Response time
T
Temperature
characteristics
W
Water hammer
A type of variable output that has a value proportional to the measured quantity. When
the analogue output is in the range of 1 to 5 V or 4 to 20 mA, it will vary continuously,
following the change of flow
A phenomenon that may occur in a fluid moving at high speed. In the parts of the fluid
where the pressure is low, vapour bubbles form and then rapidly collapse. If cavitation
is present for a prolonged period, exposed surfaces will be damaged; this is called
cavitation damage or erosion.
Range of fluid temperature that can be measured by the product.
Stands for "full span" or "full scale", and indicates varied analogue output range at rated
value. For example, when analogue output is 1 to 5 V, F.S. = 5[V] - 1[V] = 4[V], (ref.
1%F.S. = 4[V]x1% = 0.04[V])
The maximum measuring range or change in analogue output over the maximum
measurement range.
When an object is placed in a fluid stream, a vortex will be created in the fluid on the
downstream side. This vortex is called a Karman vortex. The frequency at which the
vortices are generated is proportional to the fluid velocity, therefore it is possible to
calculate the fluid flow rate by measuring the Karman vortex frequency.
The ambient humidity range within which the product will meet all published
specifications.
The ambient temperature range within which the product will meet all published
specifications.
A part that comes into physical contact with the fluid.
The amount of variation in the analogue output or display value when the supply
pressure is changed.
The pressure beyond which the flow switch will be damaged.
The flow range within which the product will meet all published specifications.
The pressure range within which the product will meet all published specifications.
Reproducibility of the display or analogue output value, when the flow is repeatedly
changing.
Time from when the target flow is applied until the flow reaches 90% of the set value.
The amount of variation in the analogue output or display value when the ambient
temperature is changed.
A momentary steep pressure increase due the spread of pressure by closing a
contactor such as a valve for an extremely short time while there is a flow.
This pressure increase is known as water hammer or impact pressure.
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Meaning
No.PF※※-OMG0006-F