Testboy TV 450, Инструкция по эксплуатации

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TESTBOY TV 450
Resistance of earth connection
35
5.3.3 Compensation of test leads resistance
This chapter describes how to compensate the test leads resistance in both continuity
functions, R LOW
Ω and CONTINUITY (model TESTBOY TV 450 (TYPE B)).
Compensation is required to eliminate the influence of test leads resistance and the
internal resistances of the instrument on the measured resistance. The lead
compensation is therefore a very important feature to obtain correct result.
Each of R LOW
Ω and CONTINUITY (model TESTBOY TV 450 (TYPE B)) has own
compensation. symbol is displayed if the compensation was carried out
successfully.
Circuits for compensating the resistance of test leads
N/L2
L/L1 L/L1
PE/L3
N/L2
PE/L3
prolongation lead
Figure 5.13: Shorted test leads
Compensation of test leads resistance procedure
‰
Select R LOW Ω or CONTINUITY (model TESTBOY TV 450 (TYPE B)) function.
‰
Connect test cable to the instrument and short the test leads together (see figure
5.13 ).
‰
Press TEST to perform resistance measurement.
‰
Press the CAL key to compensate leads resistance.
Figure 5.14: Results with old calibration
values
Figure 5.15: Results with new calibration
values
Note:
‰
The highest value for lead compensation is 5
Ω
. If the resistance is higher the
compensation value is set back to default value.
is displayed if no calibration value is stored.