Keithley 2790, Reference Manual

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16-12 Model 2790 SourceMeter
®
Switch System Reference Manual
Verifying DC current
Check DC current accuracy by applying accurate DC currents from the DC current cali-
brator to the AMPS input of the Model 2790 and verifying that the displayed readings fall
within specified limits.
Follow these steps to verify DC current accuracy:
1. Connect the Model 2790 AMPS and INPUT LO jacks to the calibrator as shown in
Figure 16-3 . Be sure the INPUTS switch is in the FRONT position.
2. Select the DC current measurement function by pressing the DCI key.
3. Set the Model 2790 for the 20mA range.
4. Source positive and negative full-scale currents for each of the ranges listed in
Table 16-4 and verify that the readings for each range are within stated limits.
Figure 16-3
Connections for Model 2790 DC current verification
Table 16-4
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** 19.9892 to 20.01080mA
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.
F
!
F
Model 2790 SourceMeter Switch 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
RS-232 GPIB
NOTE Be sure calibrator is set for
AMPS
Calibrator (Output DC Current)
normal current output.
Model 2790
INPUT LO
OUTPUT
HI
OUTPUT LO