M-142 Multifunction Calibrator
MEATEST, s.r.o.
76
User Manual v54
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Replace the fuse holder, reconnect the power cord and switch on the calibrator. If the problem persists,
contact the manufacturer.
If an obvious fault is evidenced, e.g. a measurement range or an operating mode is not functional, the user cannot
correct the fault. Contact the manufacturer.
Hidden faults
can cause different symptoms and be caused by different causes. Usually, they cause instability of
some parameter. Hidden defects can be caused by unacceptable distortion, degraded insulation etc. In this case
contact the manufacturer.
Sometimes it seems that the calibrator has hidden defect, when the rules for correct operation are not adhered to.
In this case, the fault is caused by the operator. Most frequent cases of false “hidden defects”:
•
mains voltage out of tolerance limits or unstable
•
wrong grounding of the measurement circuit (bad connection of the ground terminal of the mains outlet, or
several ground connection when grounding loops are formed)
•
proximity to sources of intensive influence, whose products are spread through the mains or propagated by
the electromagnetic field
•
strong electrostatic or electromagnetic field which can cause major instability during calibration using higher
impedance.
