GDZX ZXHL-100P, Руководство пользователя

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Figure 1 panel layout
1
、
printer 2
、
Grounding 3
、
RS232 Interface
4
、
Power socket 5
、
Power switch 6
、
Reset
7
、
Rotating mouse 8
、
Contrast control 9
、
LCD screen
10
、
Current output I- 11
、
Current output V- 12
、
Measuring input V +
13
、
Measuring input I-
Ⅵ、
working principle
The instrument uses the current-voltage testing theory, also known as four-wire method testing
technology, schematic block diagram shown in Figure 2.
Figure 2 Test Schematic
Power source output constant current which flows through standard resistor R
0
and Rx to be
C
urr
en
tso
urc
e
Signal amplification
Signal amplification
AD CPU
LCD display
Printer
Mouse
Communicatio
Memory
Clock
R
O
I+ V+
R
X
I- V-