Electromagnetic flowmeter M910
Operation manual
51
9.3 Flowrate versus diameter
The choice of flowrate for an electromagnetic flowmeter depends on the diameter of the sensor. The higher pipe
diameter, the higher flowrate can be measured. A determining parameter for flowrates is maximum velocity of the
liquid. Maximum velocity is the speed, where the flow of liquid inside pipe is still laminar. In MAG-910 it is
limited to 10m/s (with 125% overload). Speed over 10 m/s is usually too high for industrial applications. Such
diameter of pipe is usually selected, where expected flowrate is between Q
5%
and Q
50%
.
In the table bellow applicable flowrates for various diameters is displayed in units l/s and m
3
/hr.
Flowrates [ l/s ]
Flowrates [ m3/h ]
DN
Q
1%
Q
5%
Q
N
Q
50%
Q
100%
Q
MAX
Q
1%
Q
5%
Q
N
Q
50%
Q
100%
Q
MAX
10
0,01 0,04
0,20
0,39 0,79
0,98
0,03 0,14
0,80 1,41 2,83
3,53
15
0,02 0,09
0,50
0,88 1,77
2,21
0,06 0,32
2,00 3,18 6,36
7,95
20
0,03 0,16
0,90
1,57 3,14
3,93
0,11 0,57
3,20 5,65 11,31 14,14
25
0,05 0,25
1,40
2,45 4,91
6,14
0,18 0,88
5,00 8,84 17,67 22,09
32
0,08 0,40
2,20
4,02 8,04 10,05 0,3
1,5
8,00 14,5 29,0
36,2
40
0,1
0,6
4,0
6,3
12,6
15,7
0,5
2,3
13,0 22,6 45,2
56,6
50
0,2
1,0
6,0
9,8
19,6
24,5
0,7
3,5
20,0 35,3 70,7
88,4
65
0,3
1,7
9,0
16,6 33,2
41,5
1,2
6,0
35,0 59,7 119,5 149,3
80
0,5
2,5
14,0
25,1 50,3
62,8
1,8
9,0
50,0 90,5 181,0 226,2
100
0,8
3,9
20,0
39,3 78,5
98,2
3
14
80
141
283
353
125
1
6
30,0
61
123
153
4
22
150
221
442
552
150
2
9
50,0
88
177
221
6
32
200
318
636
795
200
3
16
100
157
314
393
11
57
300
565
1131 1414
250
5
25
150
245
491
614
18
88
500
884
1767 2209
300
7
35
200
353
707
884
25
127
800
1272 2545 3181
350
10
48
300
481
962
1203
35
173
1000 1732 3464 4330
400
13
63
400
628 1257 1571
45
226
1300 2262 4524 5655
500
20
98
600
982 1963 2454
71
353
2000 3534 7069 8836
600
28
141
800 1414 2827 3534 102
509
3000 5089 10179 12723
700
38
192
1000 1924 3848 4811 139
693
4000 6927 13854 17318
800
50
251
1200 2513 5027 6283 181
905
5000 9048 18096 22620
900
64
318
1500 3181 6362 7952 229 1145 6000 11451 22902 28630
1000
79
393
2000 3927 7854 9817 283 1414 8000 14137 28274 35340
Q
1%
- minimum applicable flowrate (minimum flowrate with guaranteed accuracy)
Q
5%
- recommended minimum flowrate (minimum flowrate with best accuracy)
Q
N%
- recommended nominal flowrate (expected working flowrate)
Q
50%
- recommended maximum flowrate (maximum flowrate for industrial use)
Q
100%
- maximum applicable flowrate (maximum flowrate with guaranteed accuracy)
Q
MAX
- maximum applicable overload (
Q
125%
) (flowmeter is still measuring)
Table 2: M910 flowrates
A sensor diameter should be chosen to keep real flowrate between Q
5%
and Q
50%
, because in this range the
flowmeter has the best accuracy.