T R O U B L E S H O O T I N G
PROBLEM: Sensor will not sense material
CAUSE/SOLUTION:
1)Verify power is applied to the sensor.
2)Verify "Sense Adjust." Reposition adjustment clockwise therefore making the probe more sensitive to "difficult to sense" materials.
3)Verify probe coverage when sensing is expected. The sen- sor is not designed to be "tip sensitive." Permit significant probe coverage before expecting material sensing.
4)Verify electrical continuity between sensor housing and ves- sel wall.
5)Verify connection of the electronic module to the probe.
PROBLEM: Sensor remains in the "SENSE" mode even when material is absent
CAUSE/SOLUTION:
1)Verify the active probe is not in direct contact with any inter- nal vessel structure. If so, reposition sensor.
2)Verify "Sense Adjust" setting. Reposition adjustment
3)Verify there is not a large buildup of material between the active probe and the probe housing. See "Cleaning" in the "Maintenance" section of this bulletin.
PROBLEM: Sensor does not seem to hold its calibration
CAUSE/SOLUTION:
1)Verify that the "sense adjust" is positioned at ideal point as described in
2)Maximize probe coverage of material being sensed. "Difficult to detect" materials (i.e. low dielectric or light mate- rials) are more easily detected when more probe is covered. Avoid setups where "probe tip sensitivity" is required.
3)Insure electrical continuity between the probe's mounting point (3/4" NPT or 1
4)Assess the temperature swing that the electronics sees in application. Applications with "difficult to detect" materials and that experience a wide temperature swing are the most vulnerable. Consult factory for support.
PROBLEM: Output contacts perform opposite of designations (N/O, N/C)
CAUSE/SOLUTION:
1)Designations on PCB relate to relay status when in "Fail- Safe Low" mode and when no material is sensed. If "Fail- safe High" mode is used, the designations are reversed.
Swap wire terminations of N/O and N/C if necessary. Changing the
M A I N T E N A N C E
Fuse Replacement:
The fuse incorporated into the LV800 PCB is not intended for operator replacement. A qualified technician can replace the applicable fuse according to the following specifications. If nec- essary, consult the factory for additional technical assistance or for return of the LV800.
115VAC
F1: 5x20mm, 0.63A Time Lag
Littelfuse: #218.063
Bussman:
F1: 5x20mm, 0.32A Time Lag
Littelfuse: #218.032
Bussman:
Preventive Maintenance:
The LV800 design is virtually maintenance free. In typical applications, once the sensor is properly calibrated, it will oper- ate without any further attention. In abrasive applications, probe condition should be periodically observed. Although the probe's construction is made with high quality engineering plas- tics, heavy abrasion can wear away the probe's insulators. This can influence the calibration and eventually lead to sensor fail- ure. The electronics are housed in a weatherproof enclosure. In addition the PCBs are conformal coated with a silicone- based material to further prevent electrical influence by con- densation. The sensor electronics should periodically be observed for any signs of contamination caused by improper enclosure protection (i.e. insure cover is fully engaged, and that wire entries are properly sealed.)
Cleaning Requirements:
Environmental and hazardous location protection is highly dependent on the proper installation of the cover to the hous- ing. A lubricant is applied to the housing/cover threads to enhance ability to
The driven shield feature of the LV800 is designed to minimize the need for cleaning the probe portion of the sensor. In appli- cations where material
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