8.0 Calibration Checking
Check the Moisture meter Measure mode by holding the pins of the Moisture Probe
across the exposed wires of the calibration check device (Calcheck). The WME value
of correctly calibrated instruments is between 17 - 19. Instruments that register values
outside this range should be returned to Protimeter (or an official Protimeter distributor)
for servicing. There is no facility to check the calibration of the Search mode.
Working Hygrostick probes can be checked against reference Hygrostick probes, or
against known humidities. Protimeter plc recommend those Hygrostick probes that
have drifted by more than ±5 %RH are discarded and replaced. New Hygrostick
probes are available from Protimeter plc or official Protimeter distributors.
9. Care and Maintenance
The Protimeter MMS is a precision built piece of electronic equipment that will provide
many years of reliable service if the following points are observed:
i. When not in use, keep the MMS instrument in its pouch together with its accessories.
Store the kit in a stable, dust-free environment and out of direct sunlight.
ii. Remove the batteries from the instrument if it is to be stored for periods of more than
four weeks, or when the low battery power symbol appears on the display.
iii.When using the MMS in Search mode, do not slide the bulge across surfaces as this
may lead to rapid instrument case wear. The instrument should be lifted and placed
in position to prevent erosion of the instrument case.
iv. Check the condition of accessories used with the MMS instrument on a regular basis
and replace them if they become worn or damaged.
v. To preserve calibration characteristics, Hygrostick probes should not be exposed to
saturated environments. If this is unavoidable, Hygrostick probes should be replaced
on a regular basis and their calibration should be checked at frequent intervals.
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