Ahlborn ALMEMO 2390-5, Руководство по эксплуатации

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Entering the cross-section
The cross-section area CS can be entered in the ´
Flow
´ channel either directly
in the ´
CS
´ function up to a maximum of 32000 cm2 or as diameter in the ´
DN
´
function up to a maximum of 2000 mm; (see Section 5.4). When the function
channel ´
Flow
´ is selected both these functions are activated automatically.
CROSS-SECTION AREA function ´
CS
´
Select the
FUNCTION
key .... Enter cm
2
(s 5.4)
DIAMETER function ´
DN
´
Select the
FUNCTION
key... Enter mm s. 5.4
With some cross-sections or arrangements (see Manual, Section 3.5.5) a cor-
rection factor K is necessary; this can be easily programmed as a factor in the
´
Flow
´ channel; (see Section 7.5).
Displaying the volume flow
The product obtained by multiplying average velocity ¯v by cross-section area
CS is the air volume. This volume flow is calculated automatically in the functi-
on channel ´
Flow
´ and displayed as the measured value in m
3
/h.
VOLUME FLOW in the function channel ´
Flow
´:
Select by
M
▲
key Display in m
3
/hour:
6.4.6 Cyclic averaging
If you require average values periodically always over the same periods of time
(hours or days), set the cycle to this time (see Section 6.3.2) and set the avera-
ging mode to ´
CYCL
´. In this mode average value AV is formed after the start of
a measuring operation at the measuring rate; it is deleted internally each time
cycle “Z” expires. However, average value MW for the last cycle completed re-
mains in the display for the duration of the whole current cycle.
Z1 Z2 Z3
AV(Z1)
AV(Z1) AV(Z2) AV(Z3)
AV(Z2) AV(Z3) start
display
cycle
You can, with the aid of the print cycle factor, extend the period for
particular measuring points; (see Section 6.10.6)
11: 0 1 7 5
.
CS
11: 0 1 5 0
.
DN
11: 0 8 3 4
.
mh
36 ALMEMO

2390-5
Measuring operations