KROHNE VA 40-VA 45 EN - Manual (Page 17)

ELECTRICAL CONNECTIONS
4
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VA40 - VA45
www.krohne.com 09/2013 - 4000424402 MA VA40 45 R04 en
4.2.3 Connection limit switch type TG21
The type TG21 is adapted to switch amplifiers for intrinsical safe circuits in accordance to EN
60947-5-6 NAMUR.
The TG21 includes an inductive slot sensor with bistable switching performance.
The slot sensor is actuated by the dipping action of an aluminium vane. The magnet on the
dipping vane is moved by the magnet in the float and follows its movement. A magnet float is
required.
4.3 Limit switch settings
4.3.1 Setting ring type limit switch
• Untighten plastic screw 1 and move limit switch to desired operating point 2.
• Only slightly tighten screw 1! (Risk of breaking the glass)
The operating point is, as shown, at approx. half height of the ring 2.
The exact operating point is also dependent on the size of the used float!
Figure 4-4: Connection limit switch type TG21
1 Terminal -
2 Terminal +
MA_VA40_45_R04_en_424402_PRT.book Page 17 Monday, September 16, 2013 8:50 AM