Fluke 5700A Series Service Manual page 56

5700A/5720A Series II Calibrator
Service Manual
Nominal Value
(Ω)
SHORT
1
1.9
10
19
100
190
1 k
1.9 k
10 k
19 k
100 k
190 k
1 M
1.9 M
10 M
19 M
100 M
Notes:
1. For I < I
and add this error to the corresponding uncertainty or stability specification.
Error = K(I
Where: Error is in mΩ for all two-wire comp values and four-wire short, and in ppm for the remaining four-wire values.
K is the constant from the above table;
I and I
I and I
2. For I
U
error in ppm and add this error to the corresponding uncertainty or stability specification.
Error in ppm = K(I
Where: K is the constant from the above table;
I and I
I and I
1-32
Two-Wire Comp
I < I
, errors occur due to thermally generated voltages within the 5720A. Use the following equation to determine the error,
L
- I)/( I x I)
L L
are expressed in mA for short to 1.9 kΩ;
L
are expressed in µ A for 10 kΩ to 100 MΩ
L
< I < I errors occur due to self-heating of the resistors in the calibrator. Use the following equation to determine the
MAX
2 2
-I )
U
are expressed in mA for short to 19 kΩ;
U
are expressed in µA for 100 kΩ to 100 MΩ
U
Current Derating Factors
Value of Derating Factor K for Over or Under Current
Four-Wire
[1]
L
4.4
4.4
4.4
4.4
4.4
4.4
4.4
4.4
4.4
5000
5000






Four-Wire
[1]
I < I I
L U
0.3
300
160
30
16
3.5
2.5
0.4
0.4
50
50
7.5
4.0
1.0
0.53
0.2
0.53
0.1
[2]
< I < I
MAX

-5
4 x10
-4
1.5 x 10
-3
1.6 x 10
-3
3 x 10
-2
1 x 10
-2
1.9 x 10
0.1
0.19
2.0
3.8
-5
2 x 10
-5
3.8 x 10
-4
1.5 x 10
-4
2.9 x 10
-3
1 x 10
-3
1.9 x 10
