Kyoritsu Electrical Instruments Works KEW MEG 3161A, Инструкция по эксплуатации

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< Simplified measurement of DC voltage >
This instrument also provides simplified measurement of DC
voltage. Multiplying 0.9 by the indicated value at AC voltage scale
provides the DC voltage value. However, the polarity isn't
indicated.
DC voltage (V) = Indicated value at AC voltage scale x 0.9 (V)
6-2 Insulation resistance measurement
Before performing any insulation test, check the maximum
voltage that may be applied to the circuit under test.
Note:
¡
Some circuits have an unstable insulation resistance, which
causes the reading to vary during measurement.
¡
The instrument may generate a high pitch tone during
measurement. This is not a failure.
¡
If the circuit under test has a large capacitive load, it may take
some time before the final reading can be obtained.
¡
On insulation resistance range, DC voltage is supplied through
Earth and Line probes, with Earth probe having positive polarity.
Earth probe should be connected to the earth conductor in the
circuit under test. Such connection is known to be more suitable
for insulation tests since an insulation resistance value
measured with the positive side connected to earth is typically
less than that taken through the reversed connection.
DANGER
¡
When the Test button or Remote control switch is pressed with
the Range switch set to an insulation resistance range position,
take care not to touch the tip of the test probe or the circuit
under test where a high voltage is present in order to avoid
possible shock hazard.
¡
Do not make measurement with the Battery cover removed.
CAUTION
Ensure that the circuit under test is de-energized prior to any
insulation testing.
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(1) Check the maximum voltage that may be applied to the circuit
under test. Set the Range switch to a desired insulation
resistance range.
(2) Connect Earth probe to the earth terminal of the circuit under
test. If the circuit is not earthed, connect Earth probe to any
appropriate conductor.
(3) Connect Line probe to the circuit under test and press the
Test button or Remote control switch.
(4) Take the reading on the scale for the selected insulation
resistance range.
(5) Release the Test button or Remote control switch and leave
the probes connected to the circuit under test to discharge
charges stored in the capacitance of the circuit.
DANGER
¡
Do not touch the circuit under test immediately after testing.
Charges stored in the capacitance of the circuit may cause
electrical shock.
¡
Leave the probes connected to the circuit under test
until the pointer returns to the left end of the scale. Never touch
the circuit before the discharging completes.
Connect side Earth terminal
source side
Load side
Circuit breaker
Remote control switch
Press the test button or remote control switch.
Select range
Test button
CAUTION
Make sure to turn
off the circuit
breaker.