Fluke 1625 User Manual page 46

1625
Users Manual
The ratio that is preset from factory is correct for the EI162X sensing
clamp
Press "START TEST" button.
Now a fully automated test sequence of all relevant parameters like auxiliary
earth electrode, probe- and earth electrode resistance, is implemented and fin-
ished with the display of the result R
1. Read out measured value R
2. Call R and R
S
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 >20 m between the earth electrode and the earth
spikes as well as to the earth spikes to each other. An accuracy test of the re-
sults 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 repo-
sitioned until the measured value RE stays constant.
Spikes wires should not run too close.
3-pole Measurement with Longer Earth Electrode Connect-
ing Leads
1. Use one of the accessory cable drums as earth electrode connecting
lead.
2. Spool off cable completely and compensate line resistance as de-
scribed in "Compensation of Earth Electrode Connecting Lead".
Time Average Measurement
If there is a warning "measured value unstable" (see "Description of Displays",
Procedure of Measurements) after a test sequence, most likely it is caused by
strong interference signals (e.g. unsteady noise voltage). Nevertheless, to get
38
Note
.
E
E
with "DISPLAY MENU".
H