KYORITSU KEW 6016, Инструкция по эксплуатации

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11. EARTH TESTS
11.1 Principles of Earth Measurement
This Earth function is to test power distribution lines, in-house wiring system, electrical
appliances etc
.
This instrument makes earth resistance measurement with fall-of-potential method, which is
a method to obtain earth resistance value Rx
by applying AC constant current I between
the measurement object E (earth electrode)
and H(C) (current electrode), and finding
out the potential difference V between E
and S(P) (potential electrode).
Rx = V / I
11.2 Earth resistance Measurement
WARNING
●The instrument will produce a maximum voltage of about 50V between terminals E-H(C)
in earth resistance function. Take enough caution to avoid electric shock hazard.
CAUTION
●When measuring earth resistance, do not apply voltage between measuring terminals.
1.Select Earth function with the Rotary Switch
2.Insert the Test Leads (MODEL7228) into the instrument. (Fig.41)
3.Test Lead connection
Stick the auxiliary earth spikes S(P) and H(C) into the ground deeply. They should be
aligned at an interval of 5-10m from the earthed equipment under test. Connect the green
wire to the earthed equipment under test, the yellow wire to the auxiliary earth spike S(P)
and the red wire to the auxiliary earth spike H(C) from terminals E, S(P) and H(C) of the
instrument in order.
Fig.40
Fig.41
Red Green
Yellow
Constant Current Generator
H(C)Current S(P)Potential
E(Earth)
Voltmeter