Amm Limit Switch Maintenance; Apr Limit Switch Maintenance; Aar Limit Switch Maintenance - Tecfluid Series LT Instruction Manual

With the potentiometer the current through the NAMUR amplifier can be modified. The
switching point must be between 1.2 mA and 2.1 mA. That is, with the current below 1.2
mA the output relay must have a state and above 2.1 mA the output relay must have the
other state.
16.3

AMM limit switch maintenance

The micro-switch (1) has a roller that runs on the cam (2).
To check the operation and correct possible misalignments, do the following steps:
Open the limit switch housing by removing the four M4 x 25 DIN 7985 screws.
Check that the magnet assembly (5) is firmly fixed to the shaft by the screw M3 x 10 DIN
913 (4).
Position the screw (4) as in the drawing (against the stop in a clockwise direction). Position
the cam (2) as in the drawing and tighten the screw (3).
If a multimeter with resistance measurement is available, connect it to terminals 1 & 2 of the
connector. Move the cam (2) slowly in both directions over the whole of its travel. The
multimeter must change from open circuit to short circuit in one direction and vice versa in
the other, when the roller is half way up the eccentric zone of the cam.
When a multimeter is not available, the above can be done by hearing the "click" when the
micro-switch (1) changes over.
NOTE: If due to bad handling of the micro-switch lever, the operation is not correct, the
micro-switch lever (1) should be bent slightly until correct operation is obtained.
16.4

APR limit switch maintenance

No special maintenance is required.
16.5

AAR limit switch maintenance

No special maintenance is required.
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