Babbitt LS2100 Loop-Powered Sensor - Manual (Page 2)

General Description
The LS2100 is a 2 –wire point level switch that detects the presence or absence of material in a bin silo, tank or
other container. The basic unit is made up of a solid stainless steel probe attached to an explosion proof
housing. Inside the explosion proof housing are all calibration adjustments and sensing electronics.
The unit is calibrated in the absence of material touching the probe and the milliamp signal on the 24VDC circuit
changes when material is detected.
THEORY OF OPERATION
The LS2100 employs a radio frequency (RF) balanced impedence bridge circuit to detect if the
probe is in contact with the material that is to be sensed. When material is not in contact with the probe, the
bridge is balanced by turning the adjustment pot to find the threshold where the red L.E.D. goes out. When
material is in contact with the probe, the bridge comes unbalanced and the comparing circuit realizes the
change. This causes a change in the milliamp load on the 24VDC circuit.
INSTALLATION
*CAUTION: ALL INSTALLATION AND WIRING MUST CONFORM TO NEC AND ALL
OTHER LOCAL ELECTRICAL CODES. TAKE SPECIAL CARE IN OBSERVING
HAZARDOUS AREA SAFETY PROCEDURES. WE ASSUME NO LIABILITY FOR
IMPROPERLY INSTALLED OR WIRED UNITS.
Inspection and Operation
After unpacking the LS2100 visually inspect the unit for any damages. Please advise the factory or your local
distributor of any damage.
Before installing the unit, a simple operational check can be performed.
On the bench, hook up the appropriate power to the Positive and Negative terminals. The operating voltage of
the LS2100 is 24VDC +/- 8 volts. The green LED should be lit when power is applied to LS2100 (green LED
should always be on when there is power to LS2100). Hold the unit so that the probe is not in contact with any surface
and touch the probe. The red LED should change state.
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