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-13-
No.PF
※※
-OMO0012-D
■
Definition and terminology
Terms
Meaning
A
Accumulated flow
The total amount of fluid that has passed through the device. If an instantaneous flow of
10 L/min continues for 5 minutes, the accumulated flow will be 10 x 5 = 50 L.
Accumulated pulse
output
A type of output where a pulse is generated every time a predefined accumulated flow
passes. It is possible to calculate the total accumulated flow by counting the pulses.
Analogue output
Outputs a value proportional to the flow rate. When the analogue output is in the range
1 to 5 V, it will vary between 1 to 5 V according to the rate of flow. The same for
analogue output of 4 to 20 mA.
Attachment
A metal part at both sides of the product to connect piping.
Auto-preset
This function calculates and sets the pressure values automatically based on the
on-going operation.
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.
Chattering
The problem of the switch output turning ON and OFF repeatedly around the Set value
at high frequency due to the effect of pulsation.
D
Digit
Minimum unit for setting/display is 1 digit. When the minimum unit for setting/display is
5 L/min, 3 digits will be 3 x 5 = 15 L/min
Display flow range
The range which can be displayed by the product with a digital display.
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] x 1% = 0.04[V])
H
Hysteresis
The difference between ON and OFF points used to prevent chattering. Hysteresis can
be effective in avoiding the effects of pulsation.
Hysteresis mode
Mode where the switch output will turn ON when the flow is greater than the Set value,
and will turn OFF when the flow falls below the Set value by the amount of hysteresis or
more.
I
Instantaneous flow
The volume of flow per unit of time. If it is 10 L/min, there is a flow of 10 L passing
through the device in 1 minute.
Internal voltage drop
The voltage drop across the product (and therefore not applied to the load), when the
switch output is ON. The voltage drop will vary with load current, and ideally should be
0 V.
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.
M
Minimum
setting/display unit
The resolution of set and display values.
If the minimum setting unit is 1
L/min, the flow can be displayed in 1 L/min units, i.e. 10,
11, 12.
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.
Summary of Contents for PF2W7 Series
Page 11: ...10 No PF OMO0012 D Model indication and How to Order...
Page 40: ...39 No PF OMO0012 D Dimensions in mm PF2W704 720 Model A PF2W704 100 mm PF2W720 106 mm...
Page 41: ...40 No PF OMO0012 D PF2W740...
Page 42: ...41 No PF OMO0012 D PF2W711...