Megger AVO 830, Руководство пользователя

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www.megger.com AVO®830 and AVO®835 23
Measurements
The Primary display shows the resistance value and the instrument sounds an audible beep dependant on the
resistance:
Resistance Beep mode
≤5 Ω Continuous beep
<5 Ω to <50 Ω Intermittent beep
≥50 Ω No beep
The continuity function can detect intermittent open and short circuits, which last as little as 10 ms
Conductance Measurement
Conductance, the inverse of resistance, is the ability of a circuit to pass current. High values of conductance
correspond to low values of resistance.
The instrument’s 1 nS to 60 nS range measures conductance with resolution of 0.01 nS. Because such small
amounts of conductance correspond to extremely high resistance, the nS range can determine the resistance of
components up 1 GΩ.
A current flows through all possible paths between the test probes, the conductance reading represents the total
conductance of all paths between the test probes. Therefore to measure the conductance of:
„
A Resistor: Disconnect at least one connection (1)
„
A Variable resistor: Disconnect at least two connections (2)
Hz
CAT III 1000V
CAT IV 600V
COM
FUSED
100mA
V
10A
Ω
AVO835
RANGE
MODE
MIN MAX
AVG
REL %
REL
Low Z
HOLD/Auto
ac+dc
APO
Lo
Hz
Hz
°F
Hz
V
Hi
A
mA
OFF
OFF
Ω °C
n S
Ω
MODE
1
2
3
1
3 2
2.
1.
nS
Ω
Fig 5: Conductance Measurement Set-up
Caution: To avoid possible damage to the instrument or to the equipment under test, make sure that
the circuit power is disconnected and all high-voltage capacitors are discharged before conductance is
measured.