SMC Networks PF2D5 Series, Руководство по эксплуатации

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No.PF
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-OMG0006-F
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Definition and terminology
Terms Meaning
A
Analogue output
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
C
Cavitation
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.
F Fluid temperature Range of fluid temperature that can be measured by the product.
F.S.
(Full span, Full scale)
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.
K
Karman vortex
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.
O
Operating humidity
range The ambient humidity range within which the product will meet all published
specifications.
Operating
temperature range The ambient temperature range within which the product will meet all published
specifications.
P
Part in contact with
fluid
A part that comes into physical contact with the fluid.
Pressure
characteristics The amount of variation in the analogue output or display value when the supply
pressure is changed.
Proof pressure The pressure beyond which the flow switch will be damaged.
R Rated flow range The flow range within which the product will meet all published specifications.
Rated pressure range The pressure range within which the product will meet all published specifications.
Repeatability
Reproducibility of the display or analogue output value, when the flow is repeatedly
changing.
Response time Time from when the target flow is applied until the flow reaches 90% of the set value.
T
Temperature
characteristics The amount of variation in the analogue output or display value when the ambient
temperature is changed.
W
Water hammer
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.