LEM A188506510, Руководство по эксплуатации

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An accuracy test of the results is made with 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.
Spike 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 display") 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 averanging 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.
Evaluation of measured value:
The diagram shows the maximum permissible value of the Earth resistance which will
not exceed a permissible limit value, taking into account the maximum usage error.