GB Intsruments GMT-18A, Руководство пользователя

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Use the following chart below as a guide to reading AC
voltage measurements:
ACV Read and
range following multiply
setting scale reading by:
10 0-10 1
50 0-50 1
250 0-250 1
1000 0-10 100
Common AC Voltage Measurements
6.1 Wall Receptacles
If the receptacle is controlled by a switch, make sure the
switch is ON. Set the function/range switch to 250 ACV.
Touch the test leads to the “hot” and “neutral” slots of the
receptacle (see fig. 5.) The needle indicator should read 120
VAC on the 0-250 scale. To test for proper grounding of the
receptacle, touch one test lead to the “hot” (narrow) side of the
receptacle, and the other test lead to the ground slot. The
tester should read 120 VAC as before. To test for proper
grounding of non- polarized receptacles (fig.6), alternately
touch the test leads between the receptacle slots and the wall
plate screw. The tester should indicate 120 VAC when one
test lead contacts the “hot” side of the receptacle. If ground
contact cannot be made on the wall plate screw, remove the
wall plate and touch the electrical box with the test lead in the
same manner as before. The tester should read 120 VAC with
one test lead touching the electrical box and the other
touching the live side of the receptacle. If not, the receptacle
is not properly grounded.
Common DC Milliamperage Measurements
It is important to point out that milliamps can also be
expressed as thousandths of an Ampere. Therefore 250
milliamps is 250 thousandths of one Amp or 1/4 of one Amp.
The milliamperage function of your multimeter is commonly
used by electronics repair technicians and hobbyists to
troubleshoot various low voltage circuits. Although not
normally used for electrical troubleshooting around the home,
this function can be used to measure the milliamperage draw
of household items such as flashlights, and other battery
operated devices that do not draw more than 250mA. In fig. 4,
the red (+) test lead is hooked up to the (+) terminal of the
lantern battery while the black (-) test lead is hooked up to the
bulb. The tester will indicate the milliamperage draw when the
flashlight switch is thrown in the ON position.
WARNING! Do not apply voltage to the test
leads while the tester is set in the milliamp
range. See #8 under For Your Safety.
1 ) Fully seat the test leads in the correct input jacks.
2) Set the function/range switch to the appropriate AC
voltage range. If the voltage is unknown, use the highest
range. If the voltage applied falls within the range of a
lower setting, reset the function/range switch to the
appropriate setting for greatest accuracy of reading.
3) Touch the test leads to the circuit under test. With AC
voltage, the polarity of the test leads is not a factor.
Figure 4
6.0 AC Voltage Measurement
Figure 5
5A
5B
Figure 6