Emotron EMX-B, Instruction Manual

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CG Drives & Automation 01-6048-01r3
Built-in functions 25
In the case where UltraRotoSense™ cannot detect a load it performs a very short
ramp as a second stage check before activating rotation alarm. During this ramp
it senses the complete motor load coming e.g. from inertia of the rotor as well as
mechanical and brush friction, air flow though rotor etc. When/If a second
stage ramp up check is performed the controller will wait for 5 minutes before
activating the next belt test. The first belt test will be performed 1 minute after
power up if the motor current is below the considered no-load level.
3.3.2 External rotation monitor
Activated by setting DIP6 to On.
DIP switch 6 in position “ON” (upwards), means rotation monitor uses an
external rotation sensor.
The rotation monitor with external rotation sensor requires a magnet fitted on
the periphery of the rotor or anywhere on the rotor body. The magnet activates
the external rotation sensor once every revolution. Should, for example, a belt
break and the rotor stops, the pulses cease and an alarm is given. The time until
the alarm is given is speed dependent and is 16 seconds at max. speed and 20
minutes at min. speed.
It is recommended to place the sensor magnet close to the rotor axis for accurate
results.
The amplitude of output pulse from the external rotation sensor should have a
value of 8V to 12V.
3.3.2.1 LED indications
When the magnet passes the sensor, this is indicated with Green LED is Lit 1
second and Red LED is Off.
NOTE: In order to use internal UltraRotoSense
TM
the load on the motor
should not be too low with the smallest heat exchangers.
If the load is too low for detection, use external rotation monitor instead.