Adam Equipment CFC SERIES, Руководство по обслуживанию

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Most load cells used in scales are not as simple as this example. They
have additional resistance elements added to compensate for
temperature variations and to set the outputs to correct voltages. The
circuit of a typical load cell is shown below.
35
0 o
hm
350
o
hm
35
0 o
hm
35
0
oh
m
A
B
C
D
lo
w
o
h
m
lo
w
o
h
m
temperature
correction
temperature
correction
+E
-S
-E
+S
BALANCED BRIDGE
10 VOLT POWER
SUPPLY
Vout = O VOLTS,
BS AND -s
A method to check the basic function and integrity of a load cell can be
done using an ohmmeter and voltmeter with up to a 10volt power supply.
Before the load cell is connected to the power supply use the ohmmeter
to measure the resistance between the wires. Typical resistance values
are:
+E to -E 410 ohms ±30 ohms
+S to -S 350 ohms ± 2 ohms
+E to +S or any other combination similar approximately 270 ohms.
If the load cell has Sense connections in addition they are connected to
the excitation internal to the load cell.
@Adam Equipment Company 2007
14