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3.4 Measuring Resistance
Model TH1942 Resistance measurement range: 500
Ω,
5
kΩ,
5
0kΩ,
5
00kΩ,
5
MΩ,
5
0MΩ
; Maximum
resolution: 10
mΩ (on
5
00Ω range)
3.4.1 Connections
Assuming Model TH1942 is under factory default conditions, the basic procedure is as follows:
1. Connect the test leads to
and COM.
2. Select resistance measurement function by pressing
3. Press
toggles auto ranging. Notice the
AUTO
annunciator is displayed with auto ranging. If
you want manual ranging, use the RANGE
and
keys to select a measurement range
consistent with expected resistance.
4. Connect test leads to the resistance as shown in Figure 3-3:
CAUTION: Do not apply more than 1000V peak
between
and COM or instrument damage
may occur.
5.
If the ―
OVL.D
‖
message is displayed, press up
key to select a higher range until a normal
reading is displayed (or press
key for auto ranging). Use the lowest possible range for the
best resolution.
6. Take readings from the display.
！
CAT
Ⅰ
(
1000V
)
CAT
Ⅱ(
300V
)
Ω
COM
20A
T1AL 250V
ALL INPUT
1KV MAX
500mA
MAX
V
1000V
MAX
DC I
AC I
Period
dB
dBm
%
Comp
Hold
Menu
Local
2nd
DC V
AC V
Ω
Freq
AC+DC
Rel
Rate
Esc
Shift
Trig
Auto
mA
POWER
ON
OFF
RESISTANCE
MED
AUTO
TH1942
50000 Count Multimeter
Note:
Source current flows from the
to COM terminals
Figure 3-3
Resistance Measurements
3.4.2 Shielding
To achieve a stable reading, it helps to shield resista
nces greater than 100kΩ. Place the resistance in a
shielded enclosure and connect the shield to the COM terminal of the instrument electrically.
