22
EB 9520 EN
Version with limit contacts
7
Version with limit contacts
One or two proximity switches can be
installed as alarm contacts (A1 and A2) as
follows:
Contact and function
Contact
made with
Image
Min – A1 as main contact
Bottom
9.2
Min – A1 as main contact
Min – A2 as pre-alarm contact
Bottom
Top
9.2
Min – A1 as main contact
Max – A2 as main contact
Bottom
Top
9.3
The max. contact can also be used as a sec-
ond min. contact, i.e. as a pre-alarm con-
tact. However, its switching point can only be
at least 15 % away from the switching point
of the main contact A1.
7.1
Electrical connection
Connect the alarm contacts A1 and A2 of
the indicator to an isolating switch amplifier
or alarm unit for power supply connection as
illustrated in Fig. 8.
The listed maximum values in the table apply
concerning the connection of proximity
switches to certified intrinsically safe circuits
in the type of protection Ex ia IIC T6 (PTB 00
ATEX 2049 X):
Type 1
Type 2
Ui
16 V
16 V
Ii
25 mA
25 mA
Pi
34 mW
64 mW
Ci
30 nF
30 nF
Li
100 mH
100 mH
T
T6
T5
T4
T6
T5
T4
73 °C 88 °C 100 °C 66 °C 81 °C 100 °C
Switching amplifier
acc. to EN 60947-5-6
51
A2
+
–
+
–
A1
52 41 42
Fig. 8:
Terminal assignment of the alarm con
-
tacts
7.2
Adjusting the alarm
contacts
Both the min. contacts A1 and A2 as well as
the combination of a min. contact A1 and
max. contact A2 can be shifted within 0 to
100 % of the adjusted measuring span to
adjust them.
The min. contact and max. contact have dif-
ferent designs. Contact is made when the
metal tag moves approx. 6 mm into the
proximity switch.
Min. contact
Always adjust the switching points according
to the decreasing characteristic. The bottom
edge of the metal tag causes the contact to
be made.
0%
0%
0%
100%
100%
100%
»
»
»
»
»
»
Adjustment range A2
Max. contact
Adjustment range A1
Min. contact
Adjustment range A1
Min. contact
M3 clamping
screw (SW 5.5)
Min. contact A2
Max. contact A2
Max. contact A1
Min. contact A1
Fig. 9:
Adjusting the alarm contacts