HP 3457A Service Manual page 70

Performance Tests
Rear Input Performance Tests (Standard Instrument) Cont'd
3457A
I n p u
t
S h o r t
S h o r t
S h o r t
S h o r t
S h o r t
2. Test the HP 3457A input offset on the 300 V, 30 V, 3 V, 300 mV and 30 mV ranges and record the
reading of each range on the Test Record provided at the end of this section. Begin with the 300 V
range t o allow any thermal voltages which might affect the readings on the lower ranges t o dissipate.
3. If any of the offset readings are beyond the limits specified in Table 4-11 and on the Test Record,
the instrument should be calibrated or repaired. Refer to Section V for calibration procedures.
3457A
Range
300
V
30
V
3
v
300 m V
30
m V
3457A
S e t
up
DCV
DCV
DCV
DCV
DCV
Table 4-1 1. DC Voltage Offset Test Limits (Rear Terminals)
4-43. DC Current Function
-
Rear Terminal Offset Test
4-44. Equipment Required. This procedure does not require any test equipment.
90
d a y l i m i t s
1. Set the H P 3457A to the DC Current function (DCI), 300 uA range, and the number of digits dis-
played (DIGITS DISP) t o six.
2. Use the Test Record t o record the current offset readings on the 300 uA, 3 niA, 30 mA. 300 mA
and 1 A ranges.
3. If any of the offset readings are beyond the limits specified in Table 4-12 and on the Test Record,
the instrument should be calibrated or repaired. Refer t o Section V for calibration procedures.
1
y e a r l i m i t s
H i g h
+000.0007
V
+
00.00020
v
+ 0.000007
V
+000.0040 m V
+
00.00385
m V
3457A
I n p u t
Open
H i g h
+000.0007
V
+
00.00020
v
+ 0.000007
V
+000.0040
m V
+ 00.00385
m V
Low
- 0 0 0 . 0 0 0 7
V
-
00.00020
v
-
0.000007
V
-000.0040
m V
-
00.00385
m V
3457A
Range
Low
- 0 0 0 . 0 0 0 7
V
-
00.00020
v
- 0 . 0 0 0 0 0 7
V
- 0 0 0 . 0 0 4 0
m V
-
00.00385 m V
Set Up
1
H i g h
I
L O W
I
H i g h
I
Low
3457A
DCI
DC I
DC I
DCI
DCI
Table 4-1 2. DC Current Offset Test Limits (Rear Terminals)
9 0
d a y l i m i t s
4-45. 2-Wire Ohms Function
-
Rear Terminal Offset Test
1
y e a r L i m i t s
4-46. Equipment Required. A low thermal short (copper wire) is required f o r this procedure.
1. Set the
HP 3457A to the 2-Wire Ohms Function, 30 Ohm range and the number of digits displayed
(DIGITS DISP) t o six.