12
COM
A
V
mA
uA
A
mA
uA
OFF
E
F
VO
LT
A
UT
O
S
CA
N
COM
A
V
mA
uA
A
mA
uA
OFF
EF
VO
LT
A
U
TO
S
CA
N
COM
A
V
mA
uA
A
mA
uA
OFF
EF
VO
LT
A
UT
O
SC
AN
3.2.2.
Non-contact electric field detector (EF mode)
It should be a long-distance In measuring high-voltage. Pay attention to safety
Electric field is a special substance exist in the charge and the variable ambient
magnetic field.
To detector Non-contact electric field (set up and connect the Meter as shown in
Figure 3-2):
1)
Set the rotary switch to the position of EF/VOLT.
2)
Press SELECT key to select non-contact electric field detector mode. When no or
less electric field is detected, the LCD shows “EF”
3)
Make the detector in the top of the meter approach to the wire. If the detector
senses electric field, the strength will be showed on LCD by “-“ not digits type.
And the buzzer will sound. Level 1 (weak) is “-“ and the level 4 (strong) is “----“.
The buzzer frequency depends on the strength of electric field also. The faster
beeper means the stronger electric field (ac voltage) is sensed.
Note:
Detection Sensibility: >36V ac rms
Detection distance: <10cm, It’s related to the source value.
Figure 3 - Non-contact electric field detector
3.2.3.
Resistance measurement
To avoid electrical shock and/or damage to the instrument, disconnect circuit power and
discharge all high-voltage capacitors before measuring resistance.
Resistance is an opposition to current flow. The unit of resistance is the ohm (
Ω
). The Meter
measures resistance by sending a small current through the circuit. Because this current flows
through all possible path between the probes, an in-circuit resistance reading represents the total
resistance of all paths between the probes.
To measure resistance ( set up the Meter as shown in figure 3-3):
1)
Set the rotary switch to
Ω
range
2)
Select auto scan or press SELECT key to select resistance measuring
mode.
3)
Connect the black and red leads to the COM and V
Ω
terminals
respectively
.
4)
Connect the test leads to the circuit being measured.
5)
Read the displayed value.
Figure 3-3
Measuring Resistance
Note:
In case of performing resistance test on circuit board, it is necessary firstly to turn off power of the
circuit board and then perform the measurement. As there may be other parallel circuits, so the
displayed value of test is not surely the actual value of the resistor.
Summary of Contents for AX-174
Page 1: ...AX 174 INSTRUCTION...