Array Measuring Option Vn - Ahlborn ALMEMO 2590-2 Operating Instructions Manual

11. Function menus

11.2.7 Array measuring Option VN

Average velocity in a flow channel is calculated
as per VDI 2080, namely by performing measur-
ing operations at particular array points in a
cross-section vertical to the pipe axis (see Man-
ual 3.5.5). To ensure that all individual values
are logged in standardized form a menu combi-
nation Array measuring specially conceived
for flow sensors is provided.
In the 1st menu the channel data and a mea-
suring point designation are entered. If a memo-
ry connector with MMC is available, channel
data already acquired can be loaded from an
existing file by means of
Channel type with k-factor, dimensions, and
number of holes are all prescribed by the
channel; the number of measuring depths
and gravity lines are used to calculate the actual measuring depths ( 11.2.6).
Entering the averaging duration in seconds ensures uniform data acquisition
per point by averaging over a fixed time. If the averaging duration is deleted, its
start and stop are prescribed by the measuring duration.
To select the 2nd menu press key(s)
It is thus possible to acquire all measuring points
from the 1st hole right through to the last hole at
all precalculated depths. The measuring opera-
tion is initiated by pressing the
then each point is acquired one after the other.
Any point can subsequently be reselected for
correction by means of the cursor keys.
To clear all measured values, if necessary, press key
The average value of the array is displayed continuously:
To cancel the measuring operation press key :
To proceed to the 3rd menu press key :
Display of volume flow in m
= Average value of flow [m/s] x cross-section [cm
It is possible to display the standardized vol-
ume referred to 20°C and 1013mbar if the tem-
perature and atmospheric pressure are mea-
sured at the measuring point in question; (see
temperature compensation 10.2.4 and atmo-
spheric pressure compensation 10.2.5).
Select the function standardized and activate :
Save data
If a memory connector with MMC is connected, all data can be saved to a special
volume flow file by pressing key :
36 ALMEMO
.
LOAD
<START>
3 /h
® 2590
AVERAGING
Sliding average, smoothing
over measuring operations
over time
over cycle
over measuring points
Array measuring
Mªª
Load file :
Meas point :
Channel type :
Width : 150
Number of holes :
Number of meas depths : 13
Averaging duration :
LOAD Mªª
< ►F >
Tmm B1
0028: --.-- --.-- --.-- --.--
0022: --.-- --.-- --.-- --.--
0015: --.-- --.-- --.-- --.--
key;
0009: --.-- --.-- --.-- --.--
0003: --.-- --.-- --.-- --.--
Average value
START Fª
< CLRA >
average val : 15.11 m¡
< ESC >
< VOL ►>
1934. m
2 ]
Volume flow standardized: Ø
Meas point :
Average value :
Save file :
STORE Fª
standardized : Ø
<STORE>
©
F © CLR
HALLE7.V01
Exhaust _V1
Rectangular
Depth : 175 mm
12
005
©F FCT
B2 B3 B4
-----mls
P VOL© CLRA
3 /h
Exhaust _V1
15.11 mls
HALLE7.V02
FCT