Keithley 2002 Repair Manual

ii
2.11.9 A/D converter ground multiplexer tests .................................................................................................. 2-52
2.11.10 Input buffer tests...................................................................................................................................... 2-55
2.11.11 Open-circuit ohms tests ........................................................................................................................... 2-56
2.11.12 20V range multiplexer tests..................................................................................................................... 2-58
2.11.13 Ohms tests................................................................................................................................................ 2-61
2.11.14 100:1 input divider test............................................................................................................................ 2-63
2.11.15 Overload tests .......................................................................................................................................... 2-64
2.11.16 Calibration/frequency compensation DAC tests ..................................................................................... 2-67
2.11.17 Regulator and switching tests.................................................................................................................. 2-70
2.11.18 Absolute value circuit X1 gain tests........................................................................................................ 2-72
2.11.19 Absolute value circuit, X10 gain tests..................................................................................................... 2-75
2.11.20 Sample and hold tests .............................................................................................................................. 2-80
2.11.21 Front end X1, /100, /500 tests.................................................................................................................. 2-84
2.11.22 /200 frequency compensation tests.......................................................................................................... 2-86
2.11.23 /750 frequency compensation tests.......................................................................................................... 2-90
2.11.24 True RMS converter and filter tests......................................................................................................... 2-94
2.11.25 Frequency tests ........................................................................................................................................ 2-96
2.11.26 Amps/low ohms tests............................................................................................................................. 2-102
2.11.27 Amps protection tests ............................................................................................................................ 2-107
2.11.28 ACA switch test..................................................................................................................................... 2-109
2.11.29 Ohms sense tests.................................................................................................................................... 2-110
3 Disassembly
3.1 Introduction ......................................................................................................................................................... 3-1
3.2 Handling and cleaning precautions...................................................................................................................... 3-1
3.2.1 PC-board handling..................................................................................................................................... 3-1
3.2.2 Solder repairs............................................................................................................................................. 3-1
3.3 Special handling of static-sensitive devices ........................................................................................................ 3-2
3.4 Case cover and shield removal ............................................................................................................................ 3-2
3.4.1 Case cover removal.................................................................................................................................... 3-2
3.4.2 Analog board top shield removal............................................................................................................... 3-2
3.5 PC-board removal................................................................................................................................................ 3-3
3.5.1 Digital board.............................................................................................................................................. 3-3
3.5.2 A/D converter board .................................................................................................................................. 3-3
3.5.3 Analog board ............................................................................................................................................. 3-3
3.6 Front panel disassembly ...................................................................................................................................... 3-4
3.7 Cooling fan removal ............................................................................................................................................ 3-5
3.8 Main CPU firmware replacement........................................................................................................................ 3-5
3.9 Instrument re-assembly........................................................................................................................................ 3-6
3.10 Assembly drawings.............................................................................................................................................. 3-6
4 Replaceable Parts
4.1 Introduction ......................................................................................................................................................... 4-1
4.2 Parts lists.............................................................................................................................................................. 4-1
4.3 Ordering information........................................................................................................................................... 4-1
4.4 Factory service..................................................................................................................................................... 4-1
4.5 Component layouts.............................................................................................................................................. 4-1
A Specifications..............................................................................................................A-1

Keithley 2002 Specifications

General

Resolution	8.5 digits
DC Voltage Accuracy	±0.0006%
Maximum DC Voltage	1000 V
Maximum AC Voltage	750 V
Maximum DC Current	3 A
Maximum AC Current	3 A
Connectivity	GPIB, RS-232
DC Voltage Range	100 mV to 1000 V
AC Voltage Range	100 mV to 750 V
Resistance Range	10 Ω to 1 GΩ
Model	2002
Category	Multimeter
Interface	GPIB, RS-232
AC Current Accuracy	±0.1%
Frequency Range	0.1Hz to 300kHz
Display	VFD
Type	Digital
Power Supply	100-240V AC, 50/60Hz
Current Range (DC)	100 μA to 3 A
Current Accuracy (DC)	±0.01%
Current Range (AC)	100 μA to 3 A
Current Accuracy (AC)	±0.1%
DC Current Range	100 μA to 3 A
AC Current Range	100 μA to 3 A