Example:
min. fail-safe mode,
relays 1a, 1b:
switch point 10%,
hysteresis 40%
relay de-energises on
alarm
#
Matrix Entry
Remarks
1
V1H0
e.g. 10
Switch point
2
-
»E«
Register entry
3
V1H1
0
Min. fail-safe mode
4
-
»E«
Register entry
5
V1H2
e.g. 40
Hysteresis —
relay energises at 50
6
-
»E«
Register entry
7
V1H3
0
De-energise on alarm
8
-
»E«
Register entry
9
V1H4
1
Assign to channel 1
10 -
»E«
Register entry
Example:
max. fail-safe mode,
relay 2a, 2b
switch point 90%
hysteresis 40%
relay follows analogue
output
assigned to channel 1
#
Matrix Entry
Remarks
1
V1H5
e.g. 90
Switch point
2
-
»E«
Register entry
3
V1H6
1
Max. fail-safe mode
4
-
»E«
Register entry
5
V1H7
e.g. 40
Hysteresis ——
relay energises at 50
6
-
»E«
Register entry
7
V1H8
1
Follow outputs
8
-
»E«
Register entry
9
V1H9
1
Assign to channel 2
10 -
»E«
Register entry
Note!
•
The switch point and hysteresis are always entered in the units of calibration or
linearisation
•
A small hysteresis prevents faulty switching due to turbulence
•
A large hysteresis allows two-point control of a pump with one relay
•
For two pairs of relays on channel 1, the hystereses can set such that one pair of
relays de-energises just as the other energises.
11 12 13
21 22 23
r
u a
11 12 13
21 22 23
r
u a
rising
falling
de-energises
h
yst
eresi
s
.
e
.g.
40%
V1H2
relay
energises
switch
point
V1H0
BA1
4
2
_
4
1
e.g. 50%
e.g. 10%
Fig. 4.15:
Limit value relay: example for minimum fail-safe
mode
31 32 33
41 42 43
r
u a
31 32 33
41 42 43
r
u a
rising
falling
relay
de-energises
h
yst
eresi
s
.
e
.g.
40%
V1H7
energises
switch
point
V1H5
BA1
4
2
_
4
2
e.g. 50%
e.g. 90%
Fig. 4.16:
Limit value relay: example for maximum fail-safe
mode
Note!
Prolevel FMC 661
Chapter 4: Level Measurement
Hauser
33
Summary of Contents for prolevel FMC 661
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