Jenquip EC10, Руководство пользователя

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5
Zero Calibration
To ensure that the platemeter accurately measures the compressed height of the
pasture the platemeter must be calibrated. This requires setting a base level of
zero so that measurements can be benchmarked against this. If the counter does
not return to zero after each “plonk” it will not record the measurement – hence
the counter will not beep.
If the counter is removed from the grooved rod or receives a severe knock it may
jump a groove on the steel shaft which will put the counter out of calibration.
It will need to be recalibrated.
To do this, work through the following steps:
1. Ensure the plate is fully down (place on a firm flat surface) and the unit is
switched off.
2. Hold the “Count” button while switching the unit on. The display will
change to “CAL” briefly and display a colon (:) followed by a number. Let’s
assume you see “.5” when you switch on. Proceed as follows:
3. The colon signifies that it is in fine calibration mode. Remove the
protective rubber bung by levering it out gently using a flat-bladed
screwdriver. Use a flat bladed screwdriver and
turn the plastic or steel shaft within the cog
anti clockwise, until the display reads “0”.
NB: the cog and steel shaft must remain
stationary. DO NOT TURN THE SHAFT BEYOND
THIS POINT OR YOU MAY DAMAGE THE
POTENTIOMETER. Once the counter reads
zero, move the counter up the full length of
the shaft. The colon will disappear once it
passes 9 and enter “clicks” mode. At the full height the display should
read approximately “50” which is 50 half centimetres. The counter has
now been calibrated successfully.
4. Switch off when you have finished, and then back on again without
pressing any buttons.
5. Test the zero calibration by raising and lowering the plate several times.
A beep should sound and the kgDM/ha displayed as the plate falls. If it
does not, repeat the steps above and retest.
If calibration fails to hold, then the potentiometer, which the cog drives, may
be damaged and will need replacing. This can occur with excessive wear, often
compounded by dust and dirt entering the dry bearing of the potentiometer.