TENTECH MTD 20KWe Manual De Uso página 18

Press the Start Pushbutton . After 5 seconds, the display should
•
indicate a stable value, close to the nominal value of the standard
resistance.
If this were not the case, the accuracy of the instrument would be out
•
of its specification and it would be necessary to adjust by a qualified
laboratory.
If you want to calibrate the earth meter in other points of the present
•
range or of other ranges, adequate standard resistances must be
used. In order to avoid errors by the test leads resistances and their
connections, the 4-wire connection is used (fig 06), with the earth
meter in its measurement function of ρ (4 pole). According to the
scale, the highest acceptable error is:
Range
0 – 20.00 kΩ
0 – 2000 Ω
0 – 200 Ω
0 – 20 Ω
When using a test resistance higher than 100 Ω, the leads and contacts
resistances are not significant, thus figure 07 configuration can be used,
with the Function Selector Switch  in the R position (3 pole).
Maximum error allowed
±(2% of the measured value + 0.2 kΩ)
±(2% of the measured value + 20 Ω)
±(2% of the measured value + 2 Ω)
±(2% of the measured value + 0.2 Ω)
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