Fluke 8502A - Input Impedance; Input Bias Current

DC
Volts
(Continued)
High Resolution
(
HI RES
or
CAL
—
6 1/2
digits)
Range Full Scale Resolution
Accuracy ±
(%
of Input
+
Number of Digits)
24 Hours 90 Days 1 Year
1 V 2.5 V 1 uV
0.001
+
6 0.002
+
8
0.004
+
9
10 V 20 V lOuV
0.001
or
6*
0.001
+
8 0.002
+
9
100
V 160 V 100 uV 0.001
+6
0.002
+
8 0.004
+
9
1000 V 1200
V
1
mV 0.001
+6
0.002
+
8 0.004
+
9
*Whicheve is greater.
DC Ratio
Ext.
Ref. Voltage Accuracy
+20V
to+40V
+
(A
+
B
+
10
ppm)
+V
.
*to+2QV
4A+B+2f
—
min.
—
^
Txrefl
'
A
=WV
dc
Range Accuracy
B
-Input
Signal Function and
Range Accuracy
V.^!^
^Minimum Allowable
External
Reference Voltage
=>Ad50/tyfe Value
of Ex^rna!
Reference Voltage
*The
formula for determining
is included
in Instrument
Operating
Characteristics
Example Calculations for External Reference Accuracy;
1. Input
=
+ 90.000V, Ext. Ref.
Input
=
30.000V (+
15V to Ext.
Ref. HI. -15V
to
Ext. Ref.
LO)
A
=
.001%+ 1 Digit B
=
.001%
+
1 Digit
Ratio Accuracy
=
+ (A
+
B
+
10
ppm)
=
+
{.001%
+
1 Digit
+
.001%+1 Digit + .001%
-
+(.CK)3%
+2 Digits)
Reading may be between 3.0003 and 2.9997
2. Input
=
1.20000V, Ext. Ref. Input
=
.12000
(V^.^
for IV Range)
A
==
.001%
+
1 Diqit,
B
=
.001% +
1
Digit,
200pDm .02%
Vxref
-12
Ratio Accuracy
=+.001% +
1 Digit
+
.001%
+1
Digit
+
.1667%)
=
+{.1687%+
2
Digits)
Reading may be between .998313 and 1.001686.
INSTRUMENT OPERATING CHARACTERISTICS
DC Volts
TEMPERATURE COEFFICIENT
(0°C
to 18°C and
28°C to 50°C)
INPUT
IMPEDANCE
Range
Temperature
Coefficient
Range
input
Impedance
100
mV
±
(3
ppm/reading
+
0.5 digit)/°C 100
mV >10,000 MQ,
IV
±(3
ppm/reading +0.1 digit)/ °C IV
>10,000
mi
10 V ±
(2
ppm/reading +
0.05 digit)/'^C*
10 V
>10,000
100 V ±
(3
ppm/reading
+
0.1 digit)/'^C* 100 V
10
1000
V
±
{3
ppm/reading
+
0.05 digit)/°C* 1000 V
10 mH
'For
High
Resolution
Multiply
Digits
by 10.
Guard
to Chassis
CO
INPUT BIAS
CURRENT
Bias Current
<±5
pA
30
Days {23'^C
±
Tc)
<±50 pA
Temperature
Coefficient
±
3
pA/°C