Low Ohm Resistance Measurement; Compensating Test Lead Resistance - BEHA UNITEST Telaris 0100 Mode D'emploi

Low-Ohm Measurement
Faulty measurement results can be caused
by mains bias and compensation procedures
caused by test loads. Therefore, several mea-
surements should be carried out and their re-
sults should be compared.
Measurement results can be saved by press-
ing key „Store" (26).
5.4 Low-Ohm Resistance Measurement
Prior to any Low-Ohm resistance measure-
ment, it must be guaranteed that no installation
parts to be tested are live. If an external voltage
is present, the instrument displays „Uext" after
the „Start" key has been pressed. The Low-Ohm
resistance measurement is then blocked. The
symbol „Uext" (5) appears if a second mea-
surement is started without foreign voltage pre-
sent.
Prior to any resistance measurement it is
possible to compensate test lead resistance
(please refer to chapter 5.4.1).
" Connect red test lead (equipped with individual
plugs) to the TELARIS 0100.
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" Plug test probes or crocodile clips onto the test
leads and connect the test leads to the
EUT.
" Set measurement range selection switch (24) to
„LOW-Ω" measurement range.
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" Now connect test leads to EUT:
" Press key „Start" (25).
" Read measurement value on display.
If „>19,99 Ω" appears on the display, the re-
sistance is higher than 19.99 Ohm.
The polarity of the test current applied may
influence the measurement result by means
of galvanic elements within the EUT. For this
reason always repeat the measurement with
reversed polarity to compare the measure-
ment results.
Possibility to store the measurement result
by pressing key „Store" (26).
5.4.1

Compensating Test Lead Resistance

TELARIS 0100 allows for compensation of test lead
resistance. The test lead resistance may amount up
to 1,99Ω. Proceed as follows:
" Short-circuit both test leads.
" Press key „COMP" (31).
If the test lead resistance has been properly
compensated for, the symbol „COMP" (15)
and the value 0.00 Ohm appears on the dis-
play. Furthermore, an acoustic signal isaudi-
ble. If the test lead resistance exceeds 1,99
Ohm, the symbol „COMP" (15) blinks twice
and the error signal is audible.
" To exit compensation mode, press key „COMP"
(31) again. If this is not carried out, compensa-
tion is maintained until the instrument is
switched off.
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