Keithley 2700, Service Manual

Page: 27 / 174

Performance Verification 1-11
Verifying DC current
Check DC current accuracy by applying accurate DC currents from the DC current calibra-
tor to the AMPS input of the Model 2700 and verifying that the displayed readings fall within
specified limits.
Follow these steps to verify DC current accuracy:
1. Connect the Model 2700 AMPS and INPUT LO jacks to the calibrator as shown in
Figure 1-3 . Be sure the INPUTS switch is in the FRONT position.
Figure 1-3
Connections for Model 2700 DC current verification
2. Select the DC current measurement function by pressing the DCI key.
3. Set the Model 2700 for the 20mA range.
4. Source positive and negative full-scale currents for each of the ranges listed in
Table 1-4 , and verify that the readings for each range are within stated limits.
Table 1-4
DCI limits
DCI range Applied DC current* Reading limits (1 year, 18°C to 28°C)
20mA
100mA
1A
3A 20.0000mA
100.0000mA
1.000000A
3.000000A** 19.89960 to 20.01040mA
99.9100 to 100.0900mA
0.999160 to 1.000840A
2.99628 to 3.00372A
* Source positive and negative currents with values shown.
** If the Fluke 5725 amplifier is not available, apply 2.2A from calibrator. Reading limits for 2.2A
input are: 2.197240 to 2.202760A.
Output HI
Output
LO
Input
LO
Note: Be sure calibrator is set for
Amps
Calibrator (Output DC Current)
normal current output.
Model 2700
Model 2700 Multimeter / Data Acquisition System
RANGE
!
F
500V
PEAK
FRONT/REAR
3A 250V
AMPS
HI
INPUT
LO
SENSE
Ω
4 WIRE
INPUTS
350V
PEAK
1000V
PEAK
AUTO
SHIFT
LOCAL
POWER
RANGE
R
EXIT ENTER DIGITS RATE
REL FILTER TRIG EX TRIG STORE RECALL
OPEN
DCV
DCI
MATH O U T P U T RATIO
ACV ACI
Ω
2
Ω
4 FREQ
TEMP
CH AVG CONT PERIOD SENSOR
LIMITS ON/OFF DELAY HOLD
SAVE SETUP CONFIG HALT
TYPE
LSYNC TEST
MONITOR
STEP SCAN
OCOMP
CH-OFF CARD
CLOSE
Integra Series
RS-232 GPIB