4
ELECTRICAL CONNECTIONS
26
H250 M40
www.krohne.com
03/2020 - 4000640706 - MA H250-M40 R06 en
4.2 Electrical connection for indicator M40
4.2.1 Connection of the limit switches K1/K2
The M40 indicator can be fitted with a maximum of two limit switches.
The limit switch operates as a proximity switch which is activated inductively by the semicircular
metal vane of the pointer. The switching points are set using the contact pointers.
The position of the contact pointers is indicated on the scale.
The connection terminals have a pluggable design and can be removed to connect the cables.
The built-in limit switch types are shown on the nameplate of the indicator.
Figure 4-1: Design of limit switch module
1
MIN contact
2
MAX contact
3
Locking screw
4
Contact pointers
5
Connection terminal
Contact
MIN
MAX
Terminal number
1
2
3
4
5
6
Connection 2-wire NAMUR
-
+
-
+
Connection 3-wire
+
-
+
-
Connection Reed SPST
+
-
+
-
Table 4-1: Electrical connection of the limit switches