Product Alert #57
Water Level Instrument with LCD (6541)
Alkaline battery short circuit
24 January 2001
Problem
The alkaline battery (if fitted) in the 6541 Water Level Instruments can under severe vibration short to the internal metal frame resulting in catastrophic instrument failure. A cardboard insert is shipped with the unit to prevent this, but can fall out during a battery change-over in the field.
Over time, and under severe vibration, the insulating wrapping of the battery pack, and internal D-cell battery is compromised such that the offending screw(s) become live. Prolonged vibration then results in the grounded internal metal chassis shorting the battery pack. This affects instruments shipped before February 2001.
Correction
To correct the above problem fit two rubber stoppers under the battery so that the screw heads do not contact the battery-pack (stoppers with double stick tape are ideal for field upgrading). Product shipped from the factory after February 2001 shall be fitted with 20mm rubber stoppers at each of the two mounting screws located behind, and under the battery.
PLEASE NOTE:
This upgrade is only required if the instrument is fitted with a battery, and is exposed to mechanical vibration.
|
