8
Maintenance
FläktGroup
DC_9202GB 20180403_R0
Specifications are subject to alteration without notice
0
LQLF-11
p
Pa
Pa
Pa
AIR FLOW MEASUREMENT WITH Q-DYSA
®
AND ANALOGUE FLOW INDICATING INSTRUMENT
Filling screw
Level
Resetting screw
Flow indicating instrument
q-DYSA
®
flow sensor
CHECKS
The zero setting of the manometer should be checked at regular
intervals. To check the zero setting, remove the hoses connected
to the pressure connections of the manometer. Whenever the need
arises, use the resetting screw to adjust the zero setting. Top up with
manometer liquid, if required.
The measurement nozzle should be blown clean with compressed air
once or twice a year depending on the quality of the air. This can easily
be done by disconnecting the hoses from the instrument and blowing
them with compressed air to free the air passages from impurities.
Another type of pressure gauge may also be connected for use as an
alternative meter or for checking the performance of the flow indicating
instrument. In this case, fit T-nipples in the hoses to the indicating
instrument and connect them to the pressure gauge. The air flow can
be calculated by the expression:
q = 1 ·
Δ
p m
3
/s
k
where the value of k is stated on the unit rating plate and
Δ
p is the
measurement pressure in Pa.
AIR FLOW MEASUREMENT WITH Q-DYSA
®
AND ANALOGUE FLOW INDICATING INSTRUMENT
LQ-
size
1)
size 2
2)
size 1,
normal
2)
size 2,
normal
2)
size 3,
normal
2)
size 1,
reinforced
2)
size 2,
reinforced
2)
size 3,
reinforced
K-factor m
3
/s at
500 Pa K-factor
m
3
/s at
500 Pa K-factor
m
3
/s at
500 Pa K-factor
m
3
/s at
500 Pa K-factor
m
3
/s at
500 Pa K-factor
m
3
/s at
500 Pa K-factor
m
3
/s at
500 Pa
60
1,4
16,0
1,99
11,24
1,50
14,91
1,35
16,56
2,23
10,03
1,75
12,78
1,35
16,56
62
1,09
20,5
1,50
14,91
1,35
16,56
1,08
20,70
1,75
12,78
1,35
16,56
1,08
20,70
64
0,85
26,3
1,35
16,56
1,08
20,70
0,80
27,95
1,35
16,56
1,08
20,70
0,80
27,95
71
0,85
26,3
1,35
16,56
1,08
20,70
0,80
27,95
1,35
16,56
1,08
20,70
0,80
27,95
73
1,08
20,70
0,80
27,95
0,68
32,88
1,08
20,70
0,80
27,95
0,68
32,88
80
0,85
26,3
1,35
16,56
1,08
20,70
0,80
27,95
1,35
16,56
1,08
20,70
0,80
27,95
82
1,08
20,70
0,80
27,95
0,68
32,88
1,08
20,70
0,80
27,95
0,68
32,88
84
0,80
27,95
0,68
32,88
0,52
43,00
0,80
27,95
0,68
32,88
0,52
43,00
