Burkert Type 8642 - Manual (Page 8)

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english
Sensor inputs
NOTE If mechanical limit switches or feelers are employed instead
of the approved NAMUR sensors, line breakage or short
circuits will not be detected without an additional circuit. Ther
error messages generated via the bus are invalid and must
be ignored.
Monitoring the input conductor
The input conductor can be monitored by installing 2 resistors at the
mechanical switch.
Resistor Detection of
5.6 to 18 parallel to the switch Leitungsunterbrechnung
360 to 2.7 in series with the switch short circuit
Sensor input
360 to 2.7 k
5.6 to 18
k k
ATTENTION!
Select resistors of a design such that the maximum surface
temperature on occurrence of an error is lower than the
permissible maximum temperature (safety) (see EN 50014)
of the respective temperature class. The maximum output
power of the sensor inputs can be taken from the EC Design
Type Inspection Certificate.