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To ensure the integrity of the source rod, Troxler recommends
that a qualified service person inspect the gauge and the source
rod periodically.
When the source rod is pulled out of the ground and into the
safe position, the scraper ring should clean the source rod. This
ring is located on the bottom plate at the base of the gauge. The
scraper ring will keep the source area free of material that could
damage the bearings. However, some material will collect in the
cavity above the bottom plate.
To assure a long working life, clean the cavity regularly. The
frequency of cleaning can vary from every day when in wet
sands or wet concrete to a maximum of two weeks in regular
soils.
Typical problems caused by insufficient maintenance may be
the following:
♦ Difficulty raising or lowering the source rod.
♦ No “click” sound heard when the gauge is brought into the
SAFE position.
♦ Erratic moisture or density counts.
To maintain this part of the gauge, follow these steps:
1. Position the gauge as described on B-12, Working with the
Radiation Sources.
2. Stand to the side of the gauge (to limit exposure).
3. Clean the heads of the four screws that hold the bottom
plate to the base of the gauge before removing them.
4. Remove the bottom plate.
5. Inspect the cavity for dirt buildup.