Michell Instruments MDM50-HP, Руководство пользователя

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MDM50 HP Version User’s Manual
Michell Instruments 11
MAINTENANCE
5 MAINTENANCE
Routine maintenance of the MDM50-HP is confined to regular re-calibration of the
internal, removable SF72 transmitter and replacement of the filter cartridge.
5.1 Calibration
The calibration of the internal transmitter is traceable to national standards. For this
reason it should only be calibrated in an accredited, e.g. UK United Kingdom Accreditation
Service (UKAS) or US National Institute of Standards and Technology (NIST) standards
laboratory. If these facilities do not exist it is recommended that the transmitter is
returned to the manufacturer, Michell Instruments, or an approved agent. A calibration
certificate bearing a seven-point calibration is issued with each transmitter.
In most applications, annual re-calibration ensures that the stated accuracy of the SF72
transmitter is maintained.
5.2 Transmitter / Battery Replacement
To remove the transmitter, or battery pack:
1. Ensure instrument is switched off and that the battery charger, current
output and any sampling components are also disconnected.
2. Remove and retain the 10 cross-head screws from the top plate.
3. Lift the small battery pack cover in the top right corner of the instrument.
A small flat bladed screwdriver may be required to gently pry the edges
of the cover if it has become stuck to the waterproof seal underneath.
Removing this cover first will make it easier to lift the entire top panel out
of the instrument.
4. Lift the top plate of the instrument out of the case. Disconnect the battery
pack before removing the top plate completely to prevent it from straining
on the attached cable. If only replacing the battery pack, do not follow
the next two steps.
5. Undo the screw from the centre of the transmitter connecting plug and
pull off the connector.
6. Unscrew the transmitter from the block.
Fitting the replacement is simply a reversal of the above procedure. When fitting a new
transmitter it may be necessary to change the alignment of the GDSN connector (see
next page).