4. Operation and Commissioning
4.1 Instrument Functions
With Promag 31, various instrument functions can be activated or deactivated using
miniature switches (see page 33). Explanations on individual instrument functions are
given on the following pages.
➤
Creep suppression
Works setting: Switched on
Switch No. 1: ON
Note!
With the fiscal measurement system
Promag 31 the creep suppression
is always activated.
Creep suppression prevents
“false flow” in the lower part of the
measuring range from being
detected (e.g. varying liquid head at
standstill). This enables flows to be
suppressed which should not be
measured or totalled.
Cut-in point
When the velocity of the medium
is less than 0.02 m/s creep sup-
pression is activated and all output
signals (pulse and analogue sig-
nals) are set to the fall back value
(0/4 mA, logical “0”).
Cut-off point
When the velocity of the medium
again exceeds v = 0.04 m/s, creep
suppression is deactivated.
Nominal diameter
Cut-in point
Cut-off point
DIN
[mm]
ANSI
[inch]
at v = 0.02 m/s
in [m
3
/h]
at v = 0.04 m/s
in [m
3
/h]
15
1
/
2
"
0.013
0.025
25
1"
0.035
0.071
32
1
1
/
4
"
0.058
0.116
40
1
1
/
2
"
0.090
0.181
50
2"
0.141
0.283
65
2
1
/
2
"
0.239
0.478
80
3"
0.362
0.724
100
4"
0.565
1.131
125
5"
0.884
1.767
150
6"
1.272
2.545
200
8"
2.262
4.524
250
10"
3.534
7.069
300
12"
5.089
10.179
350
14"
6.927
13.854
400
16"
9.048
18.096
450
18"
11.451
22.902
500
20"
14.137
28.274
600
24"
20.358
40.715
700
28"
27.709
55.418
750
30"
31.809
63.617
800
32"
36.191
72.382
900
36"
45.804
91.609
1000
40"
56.549
113.097
1200
48"
81.443
162.860
1350
54"
103.060
206.120
1400
56"
110.836
221.672
1500
60"
127.234
254.468
1600
64"
144.764
289.528
1700
66"
163.426
326.852
1800
72"
183.218
366.436
2000
78"
226.194
452.388
b
a028
y
3
2
Hysteresis = -50% of creep rate
1
Cut-in point for suppression
2
Cut-off point for suppression
v
Creep rate
suppression
active
suppression
active
Time
Fig. 35
Promag 31
4. Operation and Commissioning
Hauser
29
Summary of Contents for promag 31
Page 4: ...Promag 31 4 Endress Hauser ...
Page 22: ...2 Mounting and Installation Promag 31 22 Endress Hauser ...
Page 28: ...Promag 31 28 Endress Hauser ...
Page 44: ...5 Fault Location and Remedies Promag 31 44 Endress Hauser ...
Page 56: ...6 Technical Data Promag 31 56 Endress Hauser ...
Page 59: ......