NI PXI-4110 Calibration Procedure
|
© National Instruments
|
17
Current Load Regulation
To verify current load regulation, use the NI 4110 in Constant Current mode and confirm that
the output current change falls within calculated limits while varying the load voltage using
different resistors. Table 12 lists the resistance values and measurements needed to complete
verification. Refer to Figure 5 for the necessary connections.
Figure 5.
Current Load Regulation Verification Connection Diagram
Complete the following steps to verify current load regulation:
1.
For each test, connect the first specified resistance (
R
1
) to the specified channel of the
NI 4110.
2.
While taking a voltage measurement with the NI 4110 (
V
1
), use the DMM in series to
measure the output current (
I
1
).
3.
Change the load from
R
1
to
R
2
and repeat the previous step.
4.
For each test, the units for all current measurements and calculations should be the same as
the
I Range
unit. Record the current and voltage measurements for both resistances.
5.
Calculate the
Current Change Limit
using the formulas shown in the following tables:
6.
Subtract the two current measurements
I
1
-
I
2
to calculate the
Current Change
. The test
passes if the
Current Change
falls within the calculated
Current Change Limit
.
Table 11.
NI 4110 Current Load Regulation Current Change Limit Formulas
Channels
Current Range
Current Change Limit
0
1 A
±2.00 × 10
-4
× (
V
1
-
V
2
)
1 and 2
20 mA
±6.00 × 10
-7
× (
V
1
-
V
2
)
1 and 2
1 A
±7.00 × 10
-5
× (
V
1
-
V
2
)
Lo
a
d
+
–
NI PXI-4110
HI
LO
DMM
C
u
rrent
Mode
+
–
A
u
xili
a
ry Power
Su
pply
NI AP
S
-4100
+
–
AUX IN +
AUX IN –
