LEM A188506510, Руководство по эксплуатации

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Remarks for the setting of earth spikes:
Before setting the earth spikes for probe and auxiliary earth electrode make sure that
the probe is set outside the potential gradient of earth electrode and auxiliary earth
electrode (see also 12.5).Such a condition is normally reached by allowing a distance
of >20m between the earth electrode and the earth spikes as well as to the earth
spikes to each other. An accuracy test of the results is made by another
measurement following repositioning of the auxiliary earth electrode or probe. If the
value stays the same, the distance is sufficient. If the measured value changes,
probe or auxiliary earth electrode must be repositioned until the measured value RE
stays constant.
Spikes wires should not run too close.
3-pole measurement with longer earth electrode connecting leads
Use one of the supplied cable drums as earth electrode connecting lead.
Spool off cable completely and compensate line resistance as described in 8.4.4,
Time average measurement:
If there is a warning "measured value unstable" (see 8. description of displays) after a
test sequence, most likely it is caused by strong interference signals (e.g. unsteady
noise voltage). Nevertheless, to get reliable values, the instrument offers the
possibility of averaging over a longer period.
Select a fixed frequency (see 8.1.2 "Control loop")
Keep the " START " button pressed until the warning " measured value unstable"
disappears. Max. averaging time is approx. 1 min.