S
witch
1
2
3
4
5
6
T
ime
za
ze
2
s
6
s
12
s
0
.
2
s
A
/
B
o
ff
o
ff
o
ff
o
ff
o
ff
0
.
5
s
A
/
B
1
)
o
ff
o
ff
o
ff
2
s
A
/
B
on
o
ff
o
ff
6
s
A
/
B
o
ff
on
o
ff
8
s
A
/
B
on
on
o
ff
12
s
A
/
B
o
ff
o
ff
on
14
s
A
/
B
on
o
ff
on
18
s
A
/
B
o
ff
on
on
20
s
A
/
B
on
on
on
T
he measuring system is continuously monitored
.
T
he
following criteria are checked
:
l
T
wo
-
wire cable on line break and shortcircuit
l
I
nterruption of the connection cable to the piezo elements
l
C
orrosion or damage of the tuning fork
(
vibrating rod
)
l
B
reak of the tuning fork
(
vibrating rod
)
l
no vibration
l
T
oo low vibrating frequency
l
M
edium penetrating from the vessel side into the sensor
I
n systems with
OPTISWITCH
level switches in conjunction
with a two
-
wire oscillator
,
a function test can be carried out
.
SU
501
E
x has an integrated test key
.
T
he test key is lowered in
the front plate of the signal conditioning instrument
.
P
ush the
test key with a suitable object
(
e
.
g
.
screwdriver
,
pen etc
.).
B
y pushing the key
,
the system is checked on the following
criteria
:
l
S
witching function of the switching outputs
l
P
otential separation of the outputs
l
T
he signal processing of the signal conditioning instrument
A
fter pushing the test key
,
the complete measuring system is
checked on correct function
.
T
he following operating condi
-
tions are simulated during the test
:
l
F
ault signal
l
E
mpty signal
1
)
S
et alternately switch
2
and
/
or
3
to
"
on
"
.
T
he times apply to the adjusted
delay mode
.
F
ault monitoring
T
est key
18
SU
501
E
x
-
S
ignal conditioning instrument
S
et up
27953
-
EN
-
050616
