Keithley 193 Service manual
Instruction Manual
Model 193
System DMM
01985, Keithley Instruments, Inc.
Instrument Division
Cleveland, Ohio, U.S.A.
Document Number 193-901-01
SAFETY PRECAUTIONS
The following safety precautions should be observed before operating the Model ‘I93
This instrument is intended for use by qualified personnel who recognize shock hazards ,Ind arc f~u~~ili.~t
with the safety precautions required to avoid possible injury. Read over the manual carefully bei~rc upcrating
this instrumen(.
Exercise extreme caution when a shock hazard is present at the instrument’s input. The American Nati,,nal
Standards Institute (ANSI) states that a shock hazards exists when voltage levels greater than XlV rms 01
42.4V peak are present. A good safety practice is to expect that a hazardous voltage is present in any unknown
circuit before measuring.
Inspect the test lends for possible wear, cracks or breaks before each use. If any defects are fl,und, wplxe
with test leads that have the same measure of safety as those supplied with the instrument.
For optimum safety do not touch the test leads or the instrument while power is applied to the circuit under
test. Turn the power off and discharge all capacitors, bcforc connecting or disconnecting the instrunwnt.
Always disconnect all unused test leads from the instrument.
Do not touch any object which could provide a current path to the common side of the circuit under test
or power line (earth) ground. Always make measurements with dry hands while standing on a dry, ill-
s&ted surface, capable of withstanding the voltage being measured.
Exercise extreme safety when testing high energy power circuits (AC line or mains, ctc). Refer tu the fligh
Energy Circuit Safety Precautions found in paragraph 2.6 (Basic Measurements).
Do not exceed the instrument’s maximum allowable input as defined in the specifications and operation
section.
SPECIFICATIONS
1 DC VOLTS
MAXIMUM
READING RESO: ~~~ -
RANGE (5% Digits)
2 V 2:lY999 V ‘I pv ‘IO ,v >~IGO 0.002 + 1 O.UO5 + 2
20 v 2~1.9999 v
200 V 219.999 V ~100 @V ~ImV IOMR
1000 v 1000.00 v ~IlTlV ~lOl”V ~IOMR 0.004+ I 0.007+ I
*When properly zerued. **Multiply digit error by IO for h’i%digit accur~y.
NMRR: Crcater than 60dB at 50 or 60Hz.
CMRR: Greater than 120dB at dc and 50 or 60Hr
(with IkO in either lead).
MAXIMUM ALLOWABLE INPUT: ~IOOOV peak.
L”‘rI”N
6% 5% RESISTANCE 23°*10C 23:’ * 5°C 23”*5’;C 0”-18°C & 28 ‘-50 ‘C TIME”’
~10 pv ~100 pv 1OMR 0.003 + 1 0.007-1- ~1 0.009 + 3 0.0007+~,1, I < Ims
INPUT 24 Hr., 90 Days,
ACCURACY (5% Digits)**
+ (%rdg + counts)
L
0.005+2
0.003+ I
0.007+ I
MAXIMUM MEASUREMENT RATES (into internal
memory, filter and multiplex off):
3% Digit 4% Digit
1000 rdg:s 333 “dg; s 25 rdg,*
AC VOLTS (Option 1930)
MAXIMUM
READING
(5% Digits)
2v 2.1Y999V ‘I ,rV
2uv 2~1.9Y99V 10 pv I 00 ,rV
2OOV 2’19.999V ~lnn pv ImV
701lV 700.00 v ‘IlllV
*Above 2000 counts. **
Abow 2OOOt1 counts; 3%+500 lypicd b&w 2OOl10. “*Multiply digit crrlw 13~ Ill fur O’~di~it .xcur.x\
RESOLUTION
6% 5’,>
IO pv ~1 + 100 0.21 + IUU
I ~+ 1nu 0.25+ IUU l1~3i+300
~I + Ino 11.25 + ~IOU ,I.35 + 301,
IOmV 1 + ‘100 0.35+ 100 o., +3un
1 Yr.,
11.008+2’ o.onu3 in I
0.007 + 2
0.009 + 3 t1.ot107 4~ 0. I < 1111’
1).1109+5 t1.0007 +03 c 1111’
***To O.Ol’%> ot step chdng~
ACCURACY (5’:~ Digits)‘*’
I (%rdg ~+ counts,
50Hz-IOkHz’
0.35 +.m, I . SUli
TEMPERATURE
COEFFICIENT ANALOG
i (%rdg + counts), TIC SETTLING
< ?,,I> 200mV 219.99YmV IO0 nV 1 uV >lGG 0.003 + 2
o.ono3i~I1. I < I”,5
5’h Digit
6’h Digit
2.5 rds 5
I +~ i,ll,
I + ml
I i .iou
RESPONSE: True root mean square, ac or ac + dc.
CREST FACTOR: Rated accuracy to 3. Specified fat
pulse widths >lOPs, peak voltage 51.36 x full scale.
AC+DC: Add 60 counts to specified accuracy.
MAXIMUM INPUT: ‘IOOOV peak ac+dc, 2x’107V*Hz.
SETTLING TIME: 0.5s to within (1.~1% uf change in
reading.
INPUT IMPEDANCE: 1MIl shunted by less than 120pF.
TEMPERATURE COEFFICIENT CO”-18°C & 28”-50°C):
ILess than +(O.lxapplicable accuracy spccification)i”C
below 50kHz; (0.2x) for 5OkHz to 100kHz. ‘Typical
ACCURACY (1 Year)
(3% Digits)
e P/ad8 + counts)
RESOLUTION
..-
18”-28°C
2+3
2+3
2+3
2+3
21~3
3dB BANDWIDTH: .i00kl I% typic,d
CMRR: C;realer than htldll at 50 ,~nd hOtI/ (Ikl! ,,w
b&IlC~).
dBV (Ref. = 1V): ACCURACY idRV
44 tii t.i7dBV
(20llmV ti, 7OtiV rms) 0.2 (I,4
-34 to 14dBV
(2OmV tc 21UlmV)
RESPONSE: True rout mean squaw, ac -+ dc.
BANDWIDTH: 0.1 to 1011~.
1 Year, 18 -28 c
INPUT ZOHz-20kHz ZOkHz-lOOklIz RESOLUTION
Il.llldB\’
I.5
7’
0 lll‘lil\’
OHMS
MAXIMUM
READING
RANGE
200 0
2 kO
20 k0
200 kl2
2MQ
2OMSl
200Mn
*When properly zeroed. **Nominal short circuit current.
***4-terminal accuracy 200R-20k range. Multiply digit error by 10 for 6%d accuracy
(5% Digits)
219.999 12
2.1Y99Y kl2
21.9999 kn
219.999 kR
2.19999MII
21.9999Mn
219.999M12
RESOLUTION
6% 5%
100 $2 lm0
lmll ~IOmR
1Omfl 1OOmn
~loomn 1 0
1 n 10 n
10 n 100 n
100 R 1 kn
CURRENT
THROUGH
UNKNOWN
‘ImA
ImA
100 PA
10 PA
1 PA
100 nA
100 n/t**
ACCURACY (5’h Digits)***
+ (%rdg + counts)
24 Hr., 90 Days, 1 Yr.,
23°+10c
0.0035+2* 0.007+2* 0.010+2*
0.0035+2 0.007+2 0.0’10+2
0.0035 + 2 0.007+2 0.010+2
u.o035+2
0.005 +2 0.010+2 0.010+2
0.040 +2 0.070+2 0.070+2
3.2 +2 3.2 +2 3.2 +2
23’+ 5°C
0.007+2 0.010+2
23”tST
TEMPERATURE
COEFFICIENT
*(%rdg+counts)l”C
O”lE°C & 28’-50°C
0.00’1 +0.7
0.001+0.1
0.001+11:1
0.001+0:1
0.001+0.1
0.010+0:1
0.230 + 0. ~1
CONFIGURATION: Automatic 2- or 4-terminal.
MAXIMUM ALLOWABLE INPUT: 350V peak or
250V rms.
DC AMPS (Option 1931)
ACCURACY
(5% Digits) TEMPERATURE
RESO-
LUTION *(%rdg+counts) #adg+counts)i”C
RANGE (5% Digits) 18~28°C
200 @A 1nA 0.09+10 0.01+0.5
2mA 1OnA 0.09+10 0.01+0.5
20mA IOOnA
200mA
2 A 1OpA
IpA
(1 Year)
0.09+10
0.09+10 O.Ol+ 0.5
0.09+ 10 0.01+0.5
COEFFICIENT
O’Q”C & 28c50T
0.0110.5
TRMS AC AMPS (Options 1930 and 1931)
ACCURACY*
45Hz to 1OkHz
(5% Digits)
RESO-
LUTION +Phrdg+counts) +(%rdg+counts)i”C
RANGE (5% Digits) 18%28T 00-18”C & 280-5OT
200 pA
2mA 1OnA 0.6+300 0.04+10
2OmA lOOnA 0.6+300 0.04 + 10
200mA
2 A IOpA 0.6+300
i *Above 2000 camts.
1nA
W
(1 Year)
0.6+300
0.6+300 0.04+10
TEMPERATURE
COEFFICIENT
0.04+10
0.04+10
MAXIMUM OPEN CIRCUIT VOLTAGE: - 7V.
OVERLOAD PROTECTION: 2A fuse (25OV), externally
accessible.
MAXIMUM VOLTAGE BURDEN: (1.25V on 2OOfiV
through 20mA ranges; 0.28V on 200mA range; 1V on
2A range.
RESPONSE: True root mean square, ac or ac + dc.
CREST FACTOR: Rated accuracy to 3. Specified for
pulse width > 1 ms, peak current 5 1.36 x full scale.
MAXIMUM VOLTAGE BURDEN: 0.25V on ZOO&V
through 2OmA ranges; 0.28V on 200mA range; 1V on
2A range.
OVERLOAD PROTECTION: 2A fuse (25OV), externally
accessible.
SETTLING TIME: 0.5s to within 0.1% of change in
reading.
dB (Ref. = ImA):
ACCURACY +dB
INPUT
-34 to +66dB
20pA to 2A
-54 to -34dB
2&A to 20fiA
1 Year, 18°-280c
45Hz-10kHr
0.3
2
RESOLUTION
O.OldB
O.OldB
TEMPERATURE
THERMO-
COUPLE
TYPE RANGE
400 to + 760°C O.l”C
J
K
? -100 t” + 400°C
E
R
s 0 to + 1768°C
R +350 t” +1821”C 1 “C
*Relative to external 0°C reference junction; ~‘xcIusivc’ of ther-
mocouple errors. Junction temperature may be external.
ml to + 1372°C O.l”C +0.5”C
100 t” + 1ooov Kl”C
0 to +‘1768”C 1 “C +3 “C
TEMPERATURE
RESO-
RANGE LUTION 1 Yr., 18”-28°C COEFFICIENT
100” to
+630”C cl.llosT)/“c
-~ 148” to
+lloo”F 0.01 “F)PC
*Excluding probe errors.
RTD TYPE: 1000 platinum; DIN 43 760 or II’TS-68, alpha
0.00385 or 0.00392, 4.wire.
MAXIMUM LEAD RESISTANCE (each lead): 4-w&,
‘Ion.
SENSOR CURRENT: 1mA
COMMON MODE REJECTION: Less than 0.005”CIV at
dc, 50Hz and 60Hz (1000 unbalance, LO driven).
MAXIMUM ALLOWABLE INPUT: 350V peak, 250V
rms.
O.Ol”C *O.~l8”C
f..Ol”F
IThermocouple) (Over IEEE Bus Only)
ACCURACY’
(1 Year)
RESOLUTION 18”-28°C
*0.5”C
O.l”C YO.S”C
kO.hT
1 “C *3 “C
j5 “C
(RTD)
4-WIRE
ACCURACY* TEMPERATURE
*(fl.rm3%+
10.3h”F
~(0.0013%+
IEEE-488 BUS IMPLEMENTATION
Multiline Commands: DCL, LLO, SDC, GET, GTI.,
UNT, UNL, SPE, SPD.
Uniline Commands: IFC, REN, EOI, SRQ, ATN.
Interface Functions: SH1, AHl, TEO, L4, LEO, SRl, RLl,
PPO, DCl, DTl, CO, El.
kogrammable Parameters: Range, Function, Zero, Inte-
gration Period, Filter, dB Reference, EOI, Trigger, Tcrminator, Delay, 500.rd Storage, Scaling, Calibration,
Display, Multiplex Of, Status, Service Request, Self f
Test, Output Format.
GENERAL
DISPLAY: 14, 0.5.in. alphanumeric LED digits with
decimal point and polarity. Function and lf:EE bus
status also displayed.
RANGING: Manual or fast autoranging.
ISOLATION: Input LO to IEEE I.0 or power line
ground: 500V max., 5x l(l%‘*tlz; greater than IIPI!
paralleled by 400pF.
DATA MEMORY: ~1 to SO(l locations, pnrgr‘~r~~n~‘~hle.
Measurement intervals selcctablc ‘Ims to 999.999sec or
triggered.
BENCH READING RATE: 5 readings:wc, cuxpt 2Ohl!I;
200MR range 2 readingsisrc.
ZERO: Control subtracts w-scale valw from subseqwnt
readings or allows value to bc programmed.
FILTER: Weighted average (exponential). I’rogr.mm~~~hl~
weighting: 1 to li:.
WARMUP: ~1 hour to rated accur<rv.
OPERATING ENVIRONMENT: 0 -5iPC. (I%> to 80%
relative humidity up to 3PC; linearly dcr.lte 3%
RHPC. 35°C to 50°C (extent 2lIOM11 rr,nx: tl”,,, t,, 60%
RH up to 28°C). ’
STORAGE ENVIRONMENT: -25:’ to +hS’C.
POWER: ‘lO5-125V or ZlO-250V (internal switch selected),
50Hz or 60Hz, 40VA maximum 9(1-IlOV & 180.22OV
versions available upon request.
CONNECTORS: Analog: Switch s&ctabte front (>r rt’x,
safety input jacks. Digital: TRIGGEt< input and VOt.‘I~~
METER COMPLETE output on re.,r panel, HNCs.
DIMENSIONS, WEIGHT: 89mm high x 43Hmm wide
x 441mm deep (3’12 in. x 17’11 in, x l7:, in.). Net
weight 33kg (15 Ibs.).
ACCESSORIES AVAILABLE:
Model 160OA: High Voltage I’robc
Model 1641: Kelvin Test Lead Set
Model 1651:
Model 1681: Clip-On Test Lead Set
Model 1682A: RF Probe
Model 1685: Clamp-On Current Probe
Model 1751: Gener.71 I’urpw Test Leads
Model 1754: Universal Test Lead Kit
Model 1930: True RMS ACV Option
Model 1931: Current Option
Model 1938: Fixed Rack Mounting Kit
Model 1939: Slide Rack Mounting Kit
Model 7007-l: Shielded IEEE-488 Cable, lm
Model 7007-2: Shielded IEEE-488 Cable. 2m
Model 7008.3: IEEE-488 Cable, 3 ft. (0.9m)
Model 7008-6: IEEE-488 Cable, 6 ft. (l&m)
Specifications subject to change withut tnm~c,.
50.Ampere Shunt
,,
j
TABLE OF
CONTENTS
SECTION
1.1 INTRODUCTION
1.2
3.3
‘I .4
1.5 SAFETY SYMBOLS AND TERMS
‘I .6 SI’ECIFKATIONS
1.7
1.8
1.9
‘I.10
l-GENERAL INFORMATION
.........................
FEATURES.. .............................
WARRANTY INFORMATION ..............
MANUAL ADDENDA ....................
..........
.........................
INSPECTION .............................
USING THE MODEL ‘193 MANUAL ........
GETTING STARTED
ACCESSORIES ............................
.......................
SECTION 2-BASIC DMM OPERATIONS
2.1
2.2
2.2.1
2.2.2
2.2.3
2.2.4
2.3
2.3.1
2.3.2
2.3.3
2.3.4
2.4
2.4.1
2.4.2
2.4.3
2.5
2.6
2.6.1
2.6.2
2.6.3
2.6.4
2.6.5
2.6.6
2.6.7
2.6.8
2.6.9
2.6.10
2.6.11
2.6.12
2.6.13
2.7
2.7.1
2.7.2
2.8
28.1
2.8.2
2.8.3
2.8.4
INTRODUCTION ........................
POWER UI’ I’ROCEDIJRES
Line Power.
I’ower-Up Scquc”ce, ....................
Factory Default Conditions ..............
User Programmed Conditions ............
FRONT PANEL FAMII~.IARIZATION ........
Display and Indicators ...................
Co”tnlls
Input Terminals
C&rent Fuse
REAR PANEL FAMILIARIZATION
Connectors and Terminals ................
Calibration Switch ......................
Line Fuse..
ERR013 AND WARNING DISI’LAY MESSAGES
BASIC MEASUI~EMFN’I‘S.......................................................~~~~.~
Warmup Period ................................................................
...................................................................................
Zero
Filter...................................................~
DC V<,ltage Measurements
Lw+Level Measurement Considerations
TRMS AC Voltage
Resistance
Current Measurements (DC or TRMS AC)
RTD Temperature Measurements
dB Measurements
dB Measurement Considerations and Applications
TRMS AC + DC Measurcm~nts
TRMS Considerations
DATA STORE
Storing Data
Recalling Data ............................................................................
FRONT PANEL PROGRAMS ................................................................
Cursor and Data Entry
Program TEMP ...........................................................................
Program AC + DC (Low Frequency AC).
Program dB
............................
................................
........................
............................
.......
Measurements
Measurements
........................................................................
.........
.........
..,
...
................
..........
... ............
......... ..
....... ..
..................................................................
................................ ..................
..........................................................
................................................................
....................................................................
.............
..,
..............
....................................................................
... ... ...................................
... ...
... ... ...
........................ ........ ....
.................................
.............
................. ...............................
.........
......................................
..........................................
..................................................
..................................................
.............
... ., .........................
................................
.............................
.................. ...
..
........... .. .... ...
..
....................... ...........
.........
....
....
~,,~ ~.,,
.........
....
,,,
...
2.8.5
2.8.6
2.8.7
2.88
2.8.9
28.10
2.8.11
2.8.12
2.8.13
2.8.14
2.8.15
2.9
2.10
2.lO10.1
2:11x2
2.10.3
Program ZERO..
Program FILTER
Program RESET
Program 4
Program 90 (Save)
Program 91 (IEEE Address)
Program 92 (Freq)
Program 93 (Diagnostics)
Program 94 (MX + B Status)
Program Y5 (Multiplexer)
Program 96 (CAL) ................................
FRONT PANEL TRIGGERING
EXTERNAL TRIGGERING
External Trigger
Voltmeter Complete
Triggering Example
.................................
..................................
..................................
.......................................
................................
........................
................................
..........................
......................
..........................
......................
..........................
..................................
..............................
..............................
SECTION 3-IEEE-488 PROGRAMMING
..........
..........
..........
..........
..........
..........
..........
..........
..........
..........
..........
..........
.........
.........
..........
..........
..........
..........
..........
..........
..........
..........
..........
..........
..........
..........
.........
.........
.........
.........
.........
.........
.........
.........
.........
2-26
2-26
2.27
2-27
2-28
2-28
2.29
2-29
2-29
2-30
2-30
2.30
2-30
2-30
2-31
2-w
3.7
3.2
3.3
3.3.1
3.3.2
3.3.3
3.4
3.4.1
3.4.2
3.4.3
3.4.4
3.4.5
3.5
3.6
3.6.1
3.6.2
3.6.3
3.7
3.7:1
3.7.2
3.7.3
3.R
38.1
3.8.2
3.8.3
3.8.4
3.9
3.9.1
3.Y.2
3.9.3
3.9.4
3.9.5
3.9.6
3.9.7
3.9.8
3.10
3.10.1
3.10.2
3.10.3
3.10.4
3.10.5
INTRODUCTION ..........................................................................
BUS DESCRIPTION ........................................................................
IEEE-488 BUS LINES .......................................................................
Data Lines..
Bus Management Lines ...................................................................
Handshake Lines
BUS COMMANDS .........................................................................
Uniline C~,mmands .......................................................................
Universal Commands ..: ..................................................................
Addressed Commands..
Unaddressed Commands ..................................................................
Device-Dependent Commands
COMMAND CODES..
COMMAND SEQUENCES.. ................................................................
Addressed Command Sequencr ............................................................
Universal Command Sequence
Device-Dependent Command Sequence
HARDWARE CONSIDERATIONS
Typical Controlled Systems
Bus Connections
Primary Address Programming. ...........................................................
SOFTWARE CONSIDERATIONS ............................................................
Controller Handler Software ..............................................................
Interface BASIC Programming Statements
Interface Function Codes .................................................................
IEEE Command Groups ..................................................................
GENERAL BUS COMMAND I’ROGIIAMMINC
REN (Remote Enable) ....................................................................
IFC(Interfacc Clear) ......................................................................
LLO (Local Lockout) .....................................................................
GTL (Go To Local) and Local .............................................................
DCL (Device Clear) ......................................................................
SDC (Send Device Clear) .................................................................
GET (Group Execute Trigger) .............................................................
Serial Polling (SI’E, SPD) .................................................................
DEVICE-DEPENDENT COMMAND PROGRAMMING, .......................................
Execute(X) ..............................................................................
Function(F) ..............................................................................
Range(R)
Zero (Z)
Filter(P)
.............................................................................
.........................................................................
..................................................................
.............................................................
.....................................................................
.............................................................
....................................................
............................................................
................................................................
.........................................................................
..................................................
..............................................
................................................................................
.................................................................................
.................................................................................
3-I
3-1
3-2
3-2
3-2
3-2
3-3
3-4
3-4
3-5
3-5
3-s
3-5
3-7
3-7
3-7
3-7
3-7
3-7
3-8
NO
s-10
i-10
3-K
s-11
1.12
3-12
3-13
3-13
3-14
3-14
3-14
3-15
3-15
3-16
3-17
3-20
3-20
3-21
3.22
3-22
ii
3.10.6
3.10.7
3.10.8
3.10.9
3.10.10
3.10.11
3.10.12
3.10.13
3.10.14
3.10.15
3.10.16
3.10.17
3.10.18
3.10.19
3.10.20
3.10.21
3.10.22
3.1023
3.11
3.11.1
3.11.2
3.12
3.13
3.13.1
3.U.2
3.13.3
3.13.4
3.13.5
3.13.6
3.13.7
Rate (S).
Trigger Mode (T)
Reading Mode (8) ........................................................................
Data Store Interval (Q) and Size (I)
Value (V) and Calibration (C)
Default Conditions (L) ....................................................................
Data Format (G)
SRQ Mask (M) and Status Byte Format.
EOIand Bus Hold-Off Modes ..........................................................
Terminator (Y) ............................................................................
status (LJ) ...............................................................................
Multiplex (A) ............................................................................
Delay (W) ................................................................................
Self-Test (J)
Hit Button (H) ...........................................................................
Display (D)
Reference Junction (0)
Exponential Filter (N)
FRONT PANEL M~SSAGTS...................................................~.~~ ..........
Bus Error
Trigger Overrun Error ..................................................................... 3-42
BUS DATA TRANSMISSION TIMES
TRANSLATOR SOFTWARE
Translator hlrmat
NEW and OLD
Combining Translator Words
Combining Translator Wurds with Kcithlcy ll%l~-488 Commands,
Executing Translator Words and Keithley IEEE Comnunds
LIST
F:ORGET ...............................................................................
.................................................................................
.........................................................................
........................................................ 3-24
.............................................................. 3-26
..........................................................................
.................................................... 3-2X
...............................................................................
.............................................................................. 3~39
....................................................................
......................................................... ..... .....
................................................................................
.........................................................
.................................................................
........................................................................
............................................................ ........
.................................... ...... .. ........
.......................... .. 3-14
......................
...........................................................................
~,
.,
....
.....
.......
3-23
3-23
3.24
3-27
3-27
3-31
3.32
3-33
3.36
3-37
3-37
3-3X
3-3’1
3-41
3-41
3.41
3-42
3-42
3-42
3-43
3-44
3-45
.%-.I?
iwli
SECTION 4--PERFORMANCE VERIFICATION
4.1
4.2
4.3
4.4
4~.5
4.5.~1
4.52
4.5.3
4.5.4
4.5.5
4.5.6
INTRODUCTION
ENVIRONMENTAL CONDITIONS
INITIAL CONDITIONS.......................................................~ ..............
RECOMMENDED TESf EQUIPMENT
VERIFICATION I~ROCEDURE
DC Volts Verification
TRMS AC Volts Verification.,
OHMS Verification
DC Current Verification
TRMS AC Current Verification
RTD Temperature Verification
... .... ...
... ...........
... ....
....................................................... ............ +I
........... . ...
......
................................................
...
........... .. ....... ..
...
...........
....................................... ...... .....
...
........ .. ..... .....
...
SECTION 5-THEORY OF OPERATION
5.1
5.2
5.3
53.1
53.2
5.3.3
5.3.4
5.4
5.5
5.6
INTRODUCTION
OVERALL FUNCTIONAL DESCRIPTION
ANALOG CIRCUITRY
Input Signal Conditioning
Multiplexer ..,
+2.1v Reference Source
Input Buffcr Amplifier
AID CONVERTER
CONTROI,ClRCUlTRY
DIGITAL CIRCUITRY ..,
........ . .......... . ..
.......................................................................
............................................................................ i-h
..
......................
....................................................................
..........................................................................
.....................................................................
.................................................................... 5~10
................
............. ..
................ ... ... ....
............. .. ..
.. ......
............
......................
............
.. ....
..........
...........
............
................ ......... .&(I
...............................
................................
,.,
...........
........ .....
......... &I
.. .. ... ..
.............. ......
............. ....
........ .............
......... ..... ..
......................
...........
4-I
&I
&I
-I-l
4.2
4~2
1~?
4-5
5-l
5-l
5-l
i-i
i-X
;~x
i-X
i-It1
...
111
5.6.1
5.6.2
5.7
Microcomputer ...........................................................................
Display Circuitry ..........................................................................
POWER SUPPLIES
SECTION 6-MAINTENANCE
.........................................................................
5-10
S-10
5-K
6.1
6.2
6.3
6.3.1
6.3.2
6.4
6.5
6.6
b.b.‘l
6.6.2
6.6.3
6.6.4
6.6.5
6.6.6
6.6.7
6.6.8
b.b.9
h.b.10
6.6.11
6.6.12
6.7
6.8
6.9
6.9.1
6.9.2
b.Y.3
6.9.4
6.9.5
6.9.b
INTRODUCTION ...........................................................................
LINE VOLTAGE SELECTION
FUSE REPLACEMENT
Line Fuse
Current F~use
MODEL 1930 TRMS ACV OPTION INSTALLATION,,
MODEL 1931 CURRENT OPTION INSTALLATION
CALIBRATION ..............................................................................
Recommended Calibration Equipment
Environmental Conditions.,
Warm-Up Period ..........................................................................
Calibration Switch .........................................................................
Front Panel
IEEE-488 Bus Calibration
Calibration Sequence .......................................................................
DC Volts Calibration
Resistance Calibration
TRMS AC Volts Calibration
DC Current Calibration.
TRMS AC Current Calibration
DISASSEMBIdY INSTRUCTIONS
SPECIAL HANDLING OF STATIC-SENSITIVE DEVICES
TROUBLESHOOTING
Recommended Test Equipment
Power-Up Self Test .......................................................................
Program 93.Self Diagnostic Program.
Power Supplies ...........................................................................
Signal Conditioning Checks
Digital and Display Circuitry Checks
.................................................................................
..............................................................................
Callbratmn
.......................................................................
.......................................................................
................................................................. 6-l
..........................................
............................................ 6-3
....................................................... 6-3
................................................................ b-3
................................................................... b-b
....................................................................... 6-7
......................................................................
................................................................ h-10
................................................................... 6.13
............................................................. 6-14
.............................................................
...................................... b-21
...................................................................... 6-21
............................................................ 6.22
.......................................................
............................................................... 6-23
....................................................... 6-23
b-l
6-l
b-1
b-2
6-2
6-3
b-3
6-3
6-5
b-7
6-8
6.15
6.22
6-23
b-23
SECTION 7-REPLACEABLE PARTS
7.1
7.2
7.3
7.4
7.5 SCHEMATIC DIAGRAMS AND COMPONENT LOCATlON DRAWINGS
iv
INTRODUCTION.. .......................................................................... 7-l
I-ARTS LIST .................................................................................
ORDERING INFORMATION ................................................................. 7-l
FACTORY SERVICE .......................................................................... 7-l
7-l
......................... 7-l
LIST OF ILLUSTRATIONS
2-l
2-2
2-3
2-4
2-5
2-6
2-7
2-8
2-9
2-10
2-u
3-l
3-2
3-3
3-4
3-5
3-6
3-7
3-8
3-9
3-10
3-11
3-12
3-13
4-1
4-2
4-3
4-4
4-5
4-6
4-7
Model 193 Front Panel
Model 193 Rear l’anel
DC Voltage Measurements ...................................................................
TRMS AC Voltage Measurements
Two’Terminal Resistance Measurements
Four-Terminal Resistance Mrasuremcnts
Current Measurements..
RTD Temperature Measurements
External Pulse Specifications
Meter Complete Pulse Specifications
External Triggering
IEEE-488 Bus Configuration
lEEE-488 Handshake Sequence
Command Groups
System Types..
Typical Bus Connector,,
IEEE-488 Connections..................................................................~~~~
Model 193 IEEE-488 Connector
Contact Assignments.,
General Data Format
SRQ Mask and Status Byte Fomr,lt
UO Status Word and Default V.llues
Ul Error Status Word..
tHit Button Command Numbers
Connections for DC Vc,lts Verification
Connections for TRMS AC Volts Verification
Connections for Ohms Verification (200%20kR) Range
Connections for Ohms Verifications (2OOk%200Mn Ranga)
Connections for DC Current Verification.
Connections for TRMS AC Current Verification
Connections for RTD Temperature Verification.
.......................................................................
........................................................................
............................................................
.......................................................
......................................... .............
....................................................................
.......................................... ... ..
....................................................... ...
.................................... ....
Example
..........................................................................
........................................................
....................................... ......... .....
.....................................................
...............................................................
.....................................................................
..................................................
............................................ ..........
.................................................. .....
.................................................................
....
............................................. ............
................................................... ......
............................................................ 3-3’1
....................
..............
.....
.................
...........
...........
,,....
?i
2?
2-12
2-l-1
Z-15
2~15
Z-lh
......
........ ...
.... .. 1-2
...
................... 3-X
.....
~,
....... ..
...
;:;;
l~.?l
2~32
3~3
3-1,
3-P
3.‘)
..
3~‘)
..
?-Ill
.%?‘I
3~2’)
3~34
1-3;
5-l
5-2
5-3
5-4
5-5
5-6
5-7
6-l
6-2
6-3
6-4
6-5
h-6
6-7
6-8
6-9
6-10
6-11
6-12
Overall Block Diagram ..............................................
Input Configuration During 2 and 4Tcmminal Resistance Measurements
Ohms Source (2kn Range Shown)
Resistance Measuwment Simplified Circuitry
JFET Multiplexer
Multiplexer Phases
A/D Converter Simplified Schematic
Models 1930 and 1931 Installation
DC Volts Calibration Configuration (2OOmV and 2V Ranges)
DC Volts Calibration Configuration (2OV-IOOOV Ranges).
Four-Wire Resistance Configuration (200%20kll Ranges)
Two-Wire Resistance Calibration Configuration (200kR.2OOMR Ranges)
Flowchart of AC Volts Calibration Procedure
TRMS AC Volts Calibration Adjustments,
TRMS AC Volts Calibration Configuration,
DC Current Calibration Configuration
TRMS AC Current Calibration Configuration
Co”“ectors
Model 193 Exploded View
...................................................
................................................
.........
...........................................................................................................................................
.................................
.........................
.................................
.............................................................
.....................................
............................ ............
.........................................
..................................................
.....................................................
....................................................
................................................ .......
..................................................
............................
(,-.l
;I::
&‘I
h-‘1
h-II
&i;
h-l-l
h-15
66;
7-l
7-2 Display Board, Component Location Drawing, Dwg. No 193.130
7-3
7-4
7%
7-6
7-7
7-8
79
7-10
7-11
Jumper Board, Component Location Drawing, Dwg. No. 193-160
Display Board, Schematic Diagram, Dwg. No. 193.116
Digital Board, Component Location Drawing, Dwg. No. 193.100
Digital Board, Schematic Diagram, Dwg. No. 193.106
Analog Board, Component Location Drawing, Dwg. No. 193.120
Analog Board, Schematic Diagram, Dwg. No. 193.126
Model 1930, Component Location Drawing, Dwg. No. 1930-100
Model 1930, Schematic Diagram, Dwg. No. 1930.106
Model 1931, Component Location Drawing, Dwg. No. 1931-100
Model 1931, Schematic Location Drawing, Dwg. No. 1931-106
...........................................
...........................................
..........................................
...........................................
................................... 7-37
.................................
................................. 7-4
.................................
................................
................................. 7-35
.................................
7-3
7-5
7.10
7-n
7.22
7-23
7-38
7-39
vi
LIST OF TABLES
2-l
2-2
2-3
2-4
2-5
2-6
2-7
2-8
3-l
3-2
3-3
3-4
3-5
3-6
3-7
3-8
3-9
3-10
3.11
3-12
3-13
3-14
3-15
3-16
3-17
Factory Default Conditions
Front
Panel Program
Error and Warning Messages .................................................................
Resistance Ranges ..........................................................................
Corresponding Voltage Reference Levels for Impedance References
Comparison of Average and TRMS Meter Readings
High Speed Data Store
Example MX + BReadillgs ..................................................................
IEEE-488 Bus Command Summary
Hexadecimal and Decimal Command Codes
Typical Addressed Command Sequence
Typical Device-Dependent Command Sequence
IEEE Contact Designation
BASIC Statements Necessary to Send Bus Commands
Model 193 Interface Function Codes
IEEE Command Groups
General Bus Commands and Associated BASIC Statements
Factory Default Conditions
Device-Dependent Command Summary
Range Command Summary
High Speed Data Store .....................................................................
SRQ Command Parameters
Bus Hold-Off Times ........................................................................
Trigger to Reading-Ready Times
Translator Reserved Words and Character
.........................................................................
................................................................... 2-l
........................................... 2.20
..................................................................... 2.22
............................................................
...................................................
.......................................................
................................................ 3-7
....................................................................
......................................... 3-11
.......................................................... 7-12
.....................................................................
.................................... 3-U
.................................................................. 3-15
......................................................
................................................................. 3-21
.................................................................
.............................................................
..................................................... 3-46
2-4
2-9
2.14
.............................. 2-18
2.27
3-l
3-i
3-i
3-c)
3-12
R-18
2-Z
3-31)
3-32
3-42
4-l
4-2
4-3
4-4
4-5
4-6
4-7
5-l
h-l
6-2
6-3
6-4
6-5
b-b
6-7
6-8
6-9
6-10
6-11
6-12
6-13
6-14
6-15
7-l
7-2
7-3
7-4
7-5
7-6
Recommeded Test Equipment.
Limits for DC Volts Verification
Limits for TRMS AC Volts Verification
Limits for Ohms Verification
Limits for DC Current Verification
Limits for AC Current Verification
Limits for RTD Temperature Verification
Ranging Information
Line Voltage Selection
Line Fuse Replacement
Current Fuse Replacement
Recommended Calibration Equipment.
DC Volts Calibration
Resistance Calibration
TRMS AC Volts (Model 1930) Calibration
DC Current Calibration
TRMS AC $wnt Calibration
Static-Sensltwe Devices
Recommended Troubleshooting Mode.
Model 193 Troubleshooting Mode
Power Supply Checks
Digital Circuitry Checks ...........................................................................................................................................
Display Circuitry Checks
Display Board, Parts List
Digital Board, Parts List
Analog Board, I’arts List
Model 1930, Parts List
Model 1931, Parts List
Model 193 Mechanical Parts List
.........................................................................
.......
......................................................................
...................................................................... h-8
.........
.......................................................................
.......................................................................
...........
...........
.....
.............
........
........
...............
................
.......................................................... ..
,,
..........
..
.....................................................................
....................................................................
............
.....................................................................
.........................................................
.....
...................
.........................
.
.... ....... ..
....................
.....................
.....................
.....................
.....................
.....................
.....................
...
............................................. h-l
.
..................................................
........................................................
................................................... h-12
......................................................
.......................................................
........................................
.._
.
.................................................................................................
...........
............................... 7-41
.....
......
......
......
......
......
4-I
-1-2
4-3
4-4
4-5
4-h
4-h
5~3
h-2
h-2
h-5
6-K
::;:
1
h-2 I
h-22
h-24
f~:;;
h-29
;-;
7%
7-32
7-37
vii/viii
SECTION 1
GENERAL INFORMATION
1.1 INTRODUCTION
The Kcithlcy Model ~IYO System DMM, with thcTRMS AC
Volt ,Ind Current options installed, is ‘I six function
,tutora”ging digital multimeter. At 6% digit rcsc>lutio”, the
IID display cn” display +2,200,(100 counts. The rang? of
this anal[,g~to-digit,ll (ND) converter is gl-cater than the
nwmal +‘l,YYY,YYY count AID c”nwrtrr used in many 6%
digit DMMs. ‘l’hc built-in IEEE-48X interfax makes the instrument fully programmable ,,ver the IEEl:-4B8 bus. With
ihc ‘TRMS ACV option and the Current option installed,
the Model ~IY3 CJ” make the f~~llowing basic
measurements:
In addition to the above Imentioned mcaurcmcnt
capabilities, the Model ‘lY3 can “lake dB and TRMS AC
+ DC meaSu1’Cnw”tS.
1.2 FEATURES
Some important Model ‘lY3 features include:
l
14 Character Alphanumwic Display+‘asy t,, read 14
segment l.EDs used for readings and front panel
messages.
l
High Speed Measurement Ratc~‘lO00 readings per
second.
l
Zero-Used to cancel offsets or establish basclincs. A
zero value can be pmgrammcd from the front panel 01
over the IEEE-4X8 bus.
l
Filter-The weighted avcragc digital filter cd” bc set f”t
1 to YY readings from the front panel or <,ver the bus.
l
Data Store-An internal buffer that can store up t” 500
readings is accessible from either the front panel or <wt’r
the bus.
l
Digital Calibration-The instrument may bc digitally
calibrated from either the front panc’l or over the bus.
. User Programmable Default Qnditions-Any instru-
ment measurement configuration can be established as
1-l
GENERAL INFORMATION
1.6 SPECIFICATIONS
Detailed Model 193 specifications may be found preceding
the Table of Contents of this manual.
l
Section 6 contains information for servicing the instrument. This section includes information on fuse replacement, line voltage selection, calibration and
troubleshooting.
l
Section 7 contains replaceable parts information.
1.7 INSPECTION
The Model 193 System DMM was carefully inspected, both
electrically and mechanically before shipment. After un-
packing all items from the shipping carton, check for any
obvious signs of physical damage that may have occurred
during transit. Report any damage to the shipping agent.
Retain and use the original packing materials in case
reshipment is necessary. The following items are shipped
with every Model 193 order:
Model 193 System DMM
Model 193 Instruction Manual
Safety Shrouded Test Leads
Additional accessories as ordered.
If an additional instruction manual is required, order the
manual package (Keithley Part Number 193-901-00). The
manual package includes an instruction manual and any
apphcable addenda.
1.8 USING THE MODEL 193 MANUAL
This manual contains information necessary for operating
and servicing the Model 193 System DMM, TRMS ACV
option and the Current option. The information is divided into the following sections:
l
Section 1 contains general information about the Model
193 including that necessary to inspect the instrument
and get it operating as quickly as possible,
l
Section 2 contains detailed operating information on using the front panel controls and programs, making connections and basic measuring techniques for each of the
available measuring functions.
l
Section 3 contains the information necessary to connect
the Model 193 to the IEEE-488 bus and program operating
modes and functions from a controller.
l
Section 4 contains performance verification procedures
for the instrument. This information will be helpful if
you wish to verify that the instrument is operating in
compliance with its stated specifications.
l
Section 5 contains a description of operating theory.
Analog, digital, power supply, and IEEE-488 interface
operation is included.
1.9 GETTING STARTED
The Model 193 System DMM is a highly sophisticated instrument with many capabilities. To get the instrument up
and running quickly use the following procedure. For com-
plete information on operating the Model 193 consult the
appropriate section of this manual.
POWW-Up
1. Plug the line cord into the rear panel power jack and
plug the other end of the cord into an appropriate,
grounded power source. See paragraph 22.1 for more
complete information.
2. Press in the POWER switch to apply power to the instrument. The instrument will power up to the XXIOVDC
range.
Making Measurements
1. Connect the supplied safety shrouded test leads to the
front panel VOLTS HI and LO input terminals. Make
sure the INPUT switch is in the out (FRONT) position.
2. To make a voltage measurement, simply connect the input leads to a DC voltage surge (up to 1OOOV) and take
the reading from the display.
3. To change to a different measuring function, simply
press the desired function button. For example, to
measure resistance, press the OHMS button.
Using
Storing Data:
1. Press the DATA STORE button. The DATA STORE in-
2. Select an interval, other than 000.000, using the 4 and
3. Press the ENTER button. The buffer sire will be
4. If a different buffer size is desired, enter the value us-
5. Press the ENTER button to start the storage process,
Data Store
dicator will turn on and a storage rate (in seconds) will
be displayed.
), and data buttons.
displayed. Size 000 indicates that data will overwrite
after 500 readings have been stored.
ing the number buttons (0 through 9).
l-2
GENERAL INFORMATION
The data store mode can bc exited at any time before the
start of the storage process by pressing the RESET button.
Once storage has commenced, the storage process can be
stopped by pressing any function button. See paragraph
2.7.1 for complete information on storing data.
Recalling Data:
1. Press the RECALL button. The buffer location of last
stored reading will be displayed.
2. To read the data at a different memory location, enter
the value using the number buttons (O-9).
3. Press the ENTER button. The reading and the memory
location will be displayed.
4. The A and V buttons can be used to read the data in
all filled memory locations.
5. ‘To read the highest, lowest and average reading stored
in the buffer, press the number 1, 2 and 3 buttons
respectively. Note that the memory location of the
highest and lowest reading is also displayed. The
average reading is displayed along with the number of
readings averaged.
The recall mode can be exited by pressing the RESET button. See paragraph 2.7.2 for complete information on data
recall.
Using Front Panel Programs
I’mgram selection is accomplished by pressing the PRGM
button followed by the button(s) that corresponds to the
program number or name. For example, to select Program
93 (IEEE status), press the PRGM button and then 9 and
1 buttons. Table 2-2 lists and briefly describes the available
front panel programs. Once a program is selected the
following general rules will apply:
1. A displayed program condition can be entered by pressing the ENTER button.
2. Program conditions that prompt the user with a flashing
digit can be modified using the data buttons (0 through
9 and *) and the cursor control buttons (manual range
buttons).
3. Programs that contain alternate conditions can be
displayed by pressing one of the manual range buttons.
Each press of one of these buttons toggles the display
between the two available conditions.
4. A program will be executed when the pressed ENTER
button causes the instrument to exit the program mode.
5. A program can be exited at any time and thus not executed, by pressing the RESET button.
Paragraph 2.8 provides the dctailcd inform,ltion for “sing
the front paw1 programs.
1.10 ACCESSORIES
The following accessories are available to c~nhancr the
Model 193% capabilities.
ModcJ l6OOB High Voltage J’robc-The Model Jhl)l)l% CAtends DMM measurements to 4OkV.
Model 1641 Kelvin Test Lead Set-The Model 1641 has
special clip leads that allow 4.terminal measurements to
be made while making only tvw connections.
Model 1651 SO-Ampere Current Shunts-l‘hr h,Judcl I651 is
an external O.OOlR *l% 4-terminal shunt, \\hich pwmits
current measurements from 0 to SOA AC or DC.
Model ~1681 Clip-On Test Lead Set-l’hc Model I681 cow
tains two leads, 1.2m (48’) long terminated with banana
plugs and spring action clip probes.
Model 16R2A RF Probe-The Model 1682A permits voltage
measurements from ~IOOkIiz to 250MHz. AC to IX transfw
accuracy is -tldB from 1OOkHz to 25OMHz at IV, peak
responding, calibrated in I<MS of d sine \\‘ave.
Model ~1751 Safety Test JLcads-J’his test Icad SC~ is supplied
with every Model 193. Finger guards and shnrudcd banxu
plugs help minimize the chance of making contact with
live circuitry.
1-3
GENERAL lNFORMAT,ON
is installed, AC + DC voltage measurements can bc made.
Field installation 01’ r~movallrcplacement of the Model 1930
will require recalibration of the Model 143 and the Model
lY30.
Model 193~1 Current Option--The Model 1931 is a plug-in
current option for the Model 793. This option allows the
instrument to measure DC current up to 2A. When both
Models lY30 and 1931 are installed, the instrument can
make TRMS AC current measurements and TRMS AC +
DC curi-ent meas”re”le”ts. Field installation requires
recalibration of the Model 193.
Model ~I938 Fixed Rack Mount-The Model ~1938 is a stationary mount kit that allows the Model 193 tube mounted
in a standard 19 inch rack.
Model 1939 Slide Rack Mount-l‘he Model 1939 is a sliding
mount kit that allows the Model 193 to be rack mounted
with the added feature of sliding the instrument forward
for cay access to the rear panel and top cover.
Model 7007 IEEE-488 Shielded Cables-The Model 7007
connects the Model 193 to the IEEE~488 bus using shielded cables to reduce electromagnetic interference (EMI). The
Model 7007-1 is one meter in length and has a EMI shirlded IEEE-488 wnnector at each end. The Model 7007.2 is
identical to the Model 7007-1, but is two meters in Icngth
Model 7008 IEEE-488 Cables-l’he Model 7008 connects the
Model 193 to the IEEE-488 bus. ‘The Model 7008-3 is 0.9m
(3 ft.) in length and has a standard IEEE-488 connector at
each end. ‘I‘hc Model 71108-6 cable is identical to the Model
7008.3, but is ~l.Hm (6 ft.) in length.
Model 8573 lEEE~488 Interface-~-rhr Model 8373 is an
IEEE-488 standard intcrfacc designed to interface the IBM
PC or X1‘ computers to Keithlcy instrumentation over the
IEEE-488 bus. The interface system contains two distinctive parts: an interfacr board containing logic to perform
the necessary hardware functions and the handler software (supplied on disk) to perform the rquircd control
functions. Thcsc twu important facets of the Model 8573
join together to give the IBM advanced capabilities over
IEEE-488 interfaceable instrumentation.
1-4
SECTION 2
BASIC DMM OPERATION
2.1 INTRODUCTION
Operation of the Model 193 may be divided into two
general categories: front panel operation and IEEE-488 bus
operation. This section contains information necessary to
use the instrument from the front panel. These functions
can also be programmed over the IEEE-488 bus, as described in Section 3.
2.2 POWER UP PROCEDURE
2.2.1 Line Power
Use the following procedure to connect the Model 193 to
line power and power up the instrument.
1. Check that the instrument is set to correspond to the
available line power. When the instrument leaves the
factory, the internally selected line voltage is marked on
the rear panel near the AC power receptacle. Ranges are
105V.125V or ZlOV-250V 50160Hz AC. If the line voltage
setting of the instrument needs to be changed, refer to
Section 6, paragraph 6.2 for the procedure. If the line
frequency setting of the instrument needs to be checked
and/or changed, utilix front panel Program 92 (see
paragraph 2.8.11) after the instrument completes the
power-up sequence.
2. Connect the female end of the power cord to the AC
receptacle on the rear panel of the instrument. Connect
the other end of the cord to a grounded AC outlet.
WARNING
The Model 193 is equipped with a 3-wire power
cord that contains a separate ground
is designed to be used with grounded outlets.
When proper connections are made, instrument
chassis is connected to power line ground.
Failure to use a grounded outlet may result in personal injury or death because of electric shock.
wire
and
2.2.2 Power-Up Sequence
The instrument can bc turned on bv pressing i” the front
panel POWER switch The switch !$:ill bc at the inner most
position when the instrument is turned 01,. LJpcrn powerup, the instrument will dn a number of tests on itself. ‘rests
are performed on memory (ROM, RAM and NVRAM). If
RAM or ROM fails, the it~strument will lock up. If E’PROM
FAILS, the message “UNCALIBRATED” will be displayed.
See paragraph 6.9.2 for a complete description of the
power-up self test and recommendations to resolve
failures.
2.2.3 Factory Default Conditions
At the factory, the Model 193 is set up so that the front
panel controls and features are initially configured to cer-
tain conditions on power-up and when program RESET
is run. These are known as the factory default conditions
and are listed in Table 2-l.
Table 2-l. Factory Default Conditions
Control/Feature
Function
Range
Resolution
Line Frequency
IEEE Address
RTD Alpha Value and scale
Zero
Zero Value
dB
dB Reference Value
AC + DC
Data Store
Recall
Filter
Filter Value
Default Condition
DCV
1ooov
6% Digits
f
.
0.00392~C
Disabled
~l0000000
Disabled
IV, 1mA
Disabled
Disabled
Disabled
Disabled
10
CAUTION
Be s.ure that the power line voltage agrees with
the indicated range on the rear panel of the instrument. Failure to observe this precaution may
result in instrument damage.
*Program 90 (save) can be used to establish the factory
default condition. However, an “UNCALIBRATED” error
will set factory default to an IEEE address of 10 and a
frequency setting of 60Hr.
2-l
OPERATION
2.2.4 User Programmed Conditions
A unique feature of the Model ~193 is that each function
“remembers” the last measurement configuration that it
was set up for (such as range, zc’ro value, filter value, ctc).
Switching back and forth betcveen functions will not alfeet the unique configuration of each function. Howcwr,
the instrument wili “forget” Ihc configurations on
pw”-dmvn.
Certain configurations can be saved by utilizing front panel
I’rugram 90. On power-up, thcsc user saved default c(,m
ditions will prevail over the factory default conditions.
Also, a DCI. (lr SDC asserted over the IEEE-4HH bus will
set the instrument to the user saved default conditions.
For more information, see paragraph 2.X.9 (I’rugram YO).
NOTE
Keep in mind that power-up deiault conditions
can br either factory default a,nditions or LISCI
saved default conditions.
2.3 FRONT PANEL FAMILIARIZATION
‘The front panel layout of the Model 1Y3 is shown in Figure
2~1. ‘The following paragraphs describe the various consponents of the front panel in detail.
POWER-The POWER switch cont~rols AC power to the instrument. Depressing and releasing the switch once turns
the power on. Depressing and releasing the switch a second time turns the power off. The correct positions for
on and off are marked on the front panel by the POWER
switch
INPUT~Thc INPUT switch connwts thcz instrument to
either the front panel input terminals (lr the war panel in-
put terminals. This witch oprrates in same manner as the
power switch. The front panel input tcmminals arc selected
when the switch is in the “out” position and the rear panel
input terminals art’ sclcctcd when the switch is in the “in”
pmition.
FUNCTlON GROUP-I’he FUNCI‘ION buttons are used
to s&cl the primary mcasurcment functions of the instru-
ment. Thcsc buttons rllsu have wwndwy functions.
DCV--The DCV button places the instrument in the DC
volts measurement Imodc. The secondary function of this
button is to enter the number 0. Set paragraph 2.h.4 iw
DCV measurements.
AC&With the ACV option installed, the ACV button
places the instrument in the AC volts measurcmcnt mode.
The secondary function of this button is to enter the
number I. See paragraph 2.66 for ACV mcasurcmcnts.
2.3.1 Display and Indicators
IXsplay-The 14 character, alphanumeric, LED display is
used to display numeric conversion data, range and function mnemonics (ix. mV) and messages.
Status Indicators-These three indicators apply to instrum
ment operation over the IEEE-488 bus. The REMOTE illdicator shows when the instrument is in the IEEE-488
remote state. ‘The TALK and LISTEN indicators show when
the instrument is in the talk and listen states respectively.
See Section 3 for detailed information on operation over
the bus.
2.3.2 Controls
All front panel controls, except the POWER and INPUT
switches, are momentary contact switches. Indicators are
located above certain feature buttons to show that they are
enabled. Included arc AUTO (autorange), ZERO, FILTER,
RECALI. and DATA STORE. Some buttons have secondary
functions that are associated with front panel program
operation. See paragraph 2-8 for detailed information on
front panel programs.
OHMS-The OfiMS button places the instrument in the
ohms measurement mode. The sccondnry function c)f this
button is to enter the number 2. See paragraph 2.6.7 fat
resistance measurements.
ACA-With the ACV option and current option installed,
the ACA button places the instrument in the AC amps
measurement mode. The secondary function of this button is to enter the number 3. See paragraph 2.6.8 for ACA
measurements.
DC-With the current option installed, the DCA button
places the instrument in the DC amps measurement mode.
The secondary function of this button is to enter the
number 4. See paragraph 2.6.8 for DCA mrasurcments.
TEMP--‘The TEMP button places the instrument in the RTD
temperature measurement mode. The secondary functions
of this button are to select the TEMI’ program (select alternate alpha value and thermometric scale) and to enter the
number 5. See paragraph 2.6.9 for RTD temperature
measureme”ts.
RANGE GROUPLl’he Aand vbuttons are used for
manual ranging and the AUTO button is used fat
autoranging. These buttons also have secondary iunctions.
2-2
OPERATION
Manual-Each tinxe the A button is pressed, the instrument will mow up one range, while the r button will
move the instrument down one range each time it is
pressed. Pressing either of these buttons will cancel
autorange, if it was previous selcctcd. The secondary func-
tions of these buttons are associated with front panel pro-
gram operation.
AUTO-The AUTO button places the instrument in the
autorange mode and turns on the AUTO indicator. While
in this mode, the instrument will go to the best range to
measure the applied signal. Autoranging is available for
all functions and ranges. Autoranging may bc cancelled
by pressing the AUTO button or one of the manual range
buttons. The secondary function of this button is to enter
the + sign.
MODIFIER GROUP-The MODIFIER buttons activate
features that arc used to enhance the nwasurcment
capabilities of the Model 193. These features in effect
modify the selected function. In addition to their primary
tasks, these buttons have secondary functions.
ZERO-The ZERO button turns on the ZERO indicator
and causes the displayed reading to be subtracted from
subsequent readings. This feature allows for zer” correction or storage of baseline values. The secondary function
of this button is to select the ZERO program. Refer to
paragraph 2.6.2 for detailed information on the zero
feature.
dB-The dB button places the instrument in the dB
measurement mode and may be used with the ACV and
ACA functions. Under factory default conditions,
measurements are rcfcrenced to 1V or ImA. Howwer, the
dB program may be used to change the reference level.
The secondary function of this button is to select the dB
program. See paragraph 2.6.10 for dB measurements.
FILTER-The FILTER button turns on the FILTER in-
dicator and causes the instrument to start weighted
averaging a number (l-99) of readings. The factory default
value is 10, but may be changed using the FILTER pro-
gram (see paragraph 2.8.6). See paragraph 2.6.3 for filter
operation. Selecting the FlLTER program is one of the
secondary functions of this button. The other secondary
function is to enter the number 6.
AC + DC-With the appropriate options installed, the AC
+ DC button (with ACV selected) places the instrument
in the AC + DC measurement mode. With the ACV option installed, VAC + DC measurements can be made.
With both the ACV and current option installed, AAC iDC measurements can be made. See paragraph 2.6.12 for
AC + DC measurements. The secondary functions of this
button are to select the AC + DC program (low frequen-
cy TRMS measurements) and to enter the number 7.
CONTROL GROUP-The CONTROI~. buttons llr<’
features that allow for the control and m;tniplil.lti~~n i,i
various aspects of instrument “peraticrn. All of these but-
tons, except I’RGM, have II secondxy function
RESOl.N-The RES0I.N button ;tll~n\,s for the s&ctiiu~
of the number of digits of displdy rrsolutim~. Each pwss
of the RESOLN button incr11~~scs resolution by one digit.
Pressing the RESOLN button after the m<lkimum wsolw
tion is reached will revert the display back tu the I(,wcst
resolution. Display resolution of 3%. 4112, 5% (Ir 6% digits
can be selected for DCV and ACV. Display wwlution ot
4% or 5% digits can be selected for DCA and ACA On
OIIMS, 3’12, 4% 5% and 6% digit rtw,luti<~” is Ilvl~ill~bl~~
on the 20011 through 2OOkll ranges. 0” the 2h,ll! .l”d ?i)hl!!
ranges, 5% and 6% digits can bc sc~lc~cted. On the ?llOhl!!
range, only 5%d resoluti~,n is av~ilablc. .The RI~SOI..~ bul-
ton has “~, effect on I”\%, freqwwy ,\C i DC (I’rogrdnl
AC + DC), ‘TEMP or dB measurcnwnts. l’hc wcondx\
function of this button is to enter lhc dccinul puint (.i.
TRIGGER/ENTER-The TRIG(;ERiENTlill butti~n is used
as a terminator fur data entry when the instrumwt is i”
the front panel progrxn mode and 11s a front p.mel trig:
ger when the data stow is xtive.
STATUSIRESE-l
STATUS-lnstrumcnt status c.1” bc displwd \vhcrr th<,
instrument is in the normal measurclncnt &,dc or Iogging readings. When the STA’I’US button is first pressed
the following current instrument conditi~,ns ca” be
displayed with the use of the A and v buttons:
Software rcvisio” level
IEEE address
Line frequency setting
Multiplexer status (on/off)
MX+B status (on/off)
MX+B values
dB reference value
Filter value (OO=filter disabled)
Zen1 status (on!off)
Zero value
Pressing the STATUS button a scctmd time takes the ill-
strument out of the status mode.
RESET-The RESET button is used to reset the instrument
back to the previously entered paranwtcr. Keyed in
parameters are only entered after the ENTER button is
pressed. If RESET is pressed with the last p‘lramrter (It
a program displayed, the program will be exited and the
instrument will return to the previous clperating state. This
button aborts back to normal “pcr.ltion when it is i” 0111’
of the following modes:
2-3
OPERATION
1. The data store is prompting for paramckrs (interval or
size).
2. The instrument is in the RECALL mode.
3. A front panel program has been selected (except Program AC+DC which is treated as a normal mcasure~
ment function (see STATUS).
Program RESET--Program RESET returns the instrument
to the factory default conditions. See paragraph 2.8.7 for
information on using this program.
DATA STORE-The DATA STORE button s&c& the 500
point data store mode of operation Paragraph 2.7 contains
a complete description of data store operation. The secondary function uf this button is to enter the number 9.
RECALLJhe RECALL button recalls and displays
readings stored in the data stow Paragraph 2.7.2 provides
a detailed procedure for recalling data. The secondary
function of this button is to enter the number 8.
I’RCM-The PRGM button places the instrument in the
front panel program mode. Table 2-2 lists the available pro@xns. Paragraph 2.8 contains descriptions and detailed
operating pnwzdures for each front panel pn,gram.
LOCAL-When the instrument is in the IEEE-488 remote
state (REMOTII indicator on), the LOCAL button will
return the instrument to front panel operation. However,
if local lockout (LLO) was asserted over the IEEE-488 bus,
the LOCAL button will be inoperative. SW Section 3 for
information on uperating the instrument over the IEEE-488
bus.
Table 2-2. Front Panel Programs
2.3.3 Input Terminals
The input terminals are intended to be used with safety
shrouded test leads to help minimize the possibility of con-
tact with live circui&. Note that the twninals are duplicated
on the rear panel and that the INPUT switch determines
which set of terminals is active.
VOI:l’S OHMS HI and I>O-The VOLTS OHMS 111 and LO
terminals are used for making DC volts, AC volts and tww
wire resistance measurements.
AMPS and LO-The AMPS and 1.0 &rminals are used for
snaking DC current and AC current nwasurcmcnts.
OHMS SENSE HI and LO-The OHMS SENSE ktl and
LO terminals arc used with the VOIDS OHMS HI and LO
terminals to make four-wire resistance measurements and
four-wire liTI1 temperature measurcnwnts.
2.3.4 Current Fuse
The current fuse protects the Model lY31 from input current overloads. The instrument can handle up lo 2A cow
tinuously or 2.2A for less than one minute. Refer tu
paragraph 6.3.2 for the currcnl fuse replacement
procedures.
2.4 REAR PANEL FAMILIARIZATION
The rear panel of the Model 7Y3 is shown in Figure 2.2.
Progran
TEMP
AC+DC
ZERO
FILTER
RESET
2-4
dB
4
90
91
92
93
94
95
96
Description
Set RTD value and scale.
Low Frequency TRMS AC + DC.
Recall/modify dB reference value.
Recall/modify zero value.
Recall/modify number of readings averaged (filter value).
Reset internal conditions to factory
default.
MX + B select.
Save current front panel setup.
Recall/modify IEEE address.
Recall/modify line frequency setting
l50160Hz).
Self-test
Set values for MX + B program.
Multiplexer on/off.
Digital calibration.
2.4.1 Connectors and Terminals
AC Receptacle-Power is applied through the supplied
power cord to the 3.terminal AC receptacle. Note that the
selected supply voltage is marked on the rear panel “ear
the connector.
Input Terminals-The rear panel input terminals perform
the sane functions as the front panel input terminals.
Paragraph 2.3.3 contains the description of the input
terminals.
IEEE-488 Connector-This connector is used to connect the
instrument to the IEEE-488 bus. IEEE interface functions
are marked above the connector.
External Trigger Input-This BNC connector is used to apply pulses to trigger the Model 193 to take one or more
readings, depending on the selected trigger mode.
OPERATION
Voltmeter Complete Output-This BNC output connector provides a pulse when the Model lY3 has completed
a reading. It is useful for triggering other instrumentation.
2.4.2 Calibration Switch
Calibration of the Model 193 can only be done if the
calibration switch is in the unlock position.
2.4.3. Line Fuse
The line fuse provides protection for the AC power line
input. Refer to paragraph 6.3.1 for the line fuse rcplacrment procedure.
2.5 ERROR AND WARNING DISPLAY
MESSAGES
Table 2-3 lists and explains the various display rncss~~~~~s
associated with incorrect front pancl opcraiion ot the
Model 193. Also included is a warning mcssagc that illdicates tu the user that hazardous \wltages (WV or nww)
are present on the input termin‘lls.
Z-5/2-6
OPERATION
-
I,/ I, T T i--l I
I, \/
I\I-r l I II,I- I
I I,-,I ,-,I
I I-l
\
-REAR
/
Figure 2-l. Model 193 Front Panel
-
-
-
-
Figure 2-2. Model 193 Rear Panel
Z-712-8
OPERATION
Table 2-3. Error and Warning Messages
Message
NEED 1930 Selected option not installed.
NEED 1931
NEED 1930.1931
“H” High Voltage: 40V or more on
NO PROGRAM
O.VERFLO KOHM Overrange-Decimal point posi-
TRIG-OVERRUN Trigger received while still pro-
CONFLICT Trying to calibrate with instrw
NOT ACV or ACA Selecting AC t DC or d6 with in-
Explanation
input.
Invalid entry while trying to
select program.
tion and mnemonics define
function and range (2kR range
shown). The number of
characters in the “OVERFLO”
message defines the display
resolution (6%d resolution
shown).
cessing reading from last
trigger.
ment in an improper state.
strument not presently in ACV
or ACA.
When making measurements in high energy circuits use
test leads that meet the following requirements:
l
Test leads should be fully insulated.
l
Only use test leads that can be connected to the circuit
(e.g. alligator clips, spade lugs, etc.) for hands-off
measurements.
l
Do not use test leads that decrease voltage spacing. This
diminishes arc protection and creates a hazardous
condition.
Use the following squence when testing power circuits:
1. De-energize the circuit using the regular installed
connect-disconnect device such as the circuit breaker.
main switch, etc.
2. Attach the test leads to the circuit under test. Use appropriate safety rated leads for this application.
3. Set the DMM to the proper function and range.
4. Energize the circuit using the installed connect-
disconnect device and make measurements without
disconnecting the DMM.
5. De-energize the circuit using the installed connect-
disconnect device.
6. Disconnect the test leads from the circuit under test.
2.6 BASIC MEASUREMENTS
The following paragraphs describe the basic procedures
for making voltage, resistance, current, temperature, dB,
and AC + DC measurements. An ACV option must be installed for ACV measurements, the current option must
be installed for DCA measurements and both options must
be installed for ACA and AAC + DC measurements.
High Energy Circuit Safety Precautions
To optimize safety when measuring voltage in high energy
distribution circuits, read and use the directions in the
following warning.
WARNING
Dangerous arca of an explosive nature in a high
energy circuit can cause severe personal injury
or death. If the meter is connected to a high
energy circuit when set to a current range, low
resistance range or any other low impedance
range, the circuit is virtually shorted. Dangerous
arcing can result even when the meter is set to
voltage range if the minimum voltage spacing is
reduced.
WARNING
The maximum common-mode input voltage (the
voltage between input LO and chassis ground) is
500V peak. Exceeding this value may create a
2.6.1 Warm Up Period
The Model 193 is usable immediately when it is first turned
on. However, the instrument must be allowed to wartn up
for at least one hour to achieve rated accuracy.
2.6.2 Zero
The zero feature serves as a means of baseline suppres-
sion by allowing a stored offset value to be subtracted from
subsequent readings. When the ZERO button is pressed,
the instrument takes the currently displayed reading as
a baseline value. All subsequent readings represent the dif-
ferences between the applied signal level and the stored
baseline.
2-9
OPERATION
A baseline level can be established for any or all measurc-
rnent functions and is remembered by each function. For
example, a ‘IOV baseline can be established on DCV, a 5V
baseline can be established on ACV and a IOkR baseline
can be established on OHMS. These levels will not be
canccllcd by switching back and forth between functions.
Once a baseline is established for a measurement function, that stored level will be the same regardless of what
range the Model lY3 is on. For example, if 1V is established
as the baseline on the 2V range, then the baseline will also
bc IV on the XIV through ‘IOOOV ranges. A zero baseline
levrl can be as large as full range.
NOTE
The following discussion on dynamic range is
based on a display resolution of 6% digits. At 5%
digit resolution, the number of counts would be
reduced by a factor of 10. At 4%d resolution,
counts would be reduced by a factor of 100 and
3%d resolution would reduce counts by a factor
of 1000.
By design, the dynamic measurement range of the Model
~193, at 6% digit resolution, is 4400000 counts (excluding
the 1000VDC and 700VAC ranges). With zero disabled,
the displayed reading range of the instrument is ~2200000
counts. With zero enabled, the Model 193 has the capabili-
ty to display +4400000 counts. This increased display
range ensures that the dynamic measurement range of the
instrument is not reduced when using a zero baseline
value. The following two examples will use the maximum
allowable zero values (+2200000 counts and -2200000
counts) to show that dynamic measurement range will not
be reduced. It is important to note that the increased
display range does not increase the maximum allowable
input level to the instrument. For example, on the 2V
range, the Model 193 will always overrange when more
than +2.2V is connected to the input.
Example l-The instrument is set to the ZVDC range and
a maximum -2,200OOOV is established as the zero value.
When -2.2OOOOOV is connected to the input of the Model
193, the display will read O.OOOOOOV. When +2.2OOOOOV
is connected to the input, the display will read
+4.4OOOOOV. Thus, the dynamic measurement range of
the Model 193 is OV to 4.4V, which is 4400000 counts.
Example 2-The instrument is still set to the 2VDC range,
but a maximum +2,2OOOOOV is the zero level. When
+2,2OOOOOV is connected to the input of the Model 193,
the display will read O.OOOOOOV. When -2.2OOOOOV is connected to the input, the display will read -4.4OOOOOV. Thus
the dynamic measurement range of the instrument is -4.4V
to OV, which is still 4400000 counts.
Zero Correction-The Model 193 must be properly zeroed
when using the 200mV DC or the 20011 range in order to
achieve rated accuracy specifications. To use ZERO for
xcro correction, perform the following steps:
Disable zero, if presently enabled, by pressing the
ZERO button. The ZERO indicator will turn off.
Select the 200mV DC or the 2000 range.
Connect the test leads to the input of the Model ‘193
and short them together. If four-wire resistance
measurements are to be made, connect and short all
four leads together.
Note: At 5% and 6% digit resolution, low measurement
techniques need to be employed. Use Kelvin test leads
or shielded test leads. See paragraph 2.6.5 for low level
measurement considerations.
Press the ZERO button. The display will read zero.
Remove the short and connect the test leads to the
signal or resistance to be measured.
Note: Test lead resistance is also compensated for when
zeroing the 20011 range with the above procedure.
Baseline Levels-Baseline values can be established by
either applying baseline levels to the instrument or by set-
ting baseline values with the front panel ZERO program.
Paragraph 2.8.5 contains the complete procedure for us-
ing the ZERO program. ‘To establish a baseline level by
applying a level to the Model 193, perform the following
steps:
1.
Disable zero, if presently enabled, by pressing the
ZERO button. The ZERO indicator will turn off.
2.
Select a function and range that is appropriate for the
anticipated measurement.
3
Connect the desired baseline level to the input of the
I
Model 193 and note that level on the display.
Press the ZERO button. The display will zero and the
4.
ZERO indicator will be enabled. The previously
displayed reading will be the stored baseline. The zero
baseline value will also be stored in Program ZERO,
replacing the previous zero value.
WARNING
If +4OV or more is present on the input terminals, the Model 193 will display the mnemonic
“H” to indicate the presence of hazardous
voltage.
For example, the
display
“00.0000HVDC” indicates than of 40V or more
is present on the input.
Disconnect the stored signal from the input and con-
5,
nect the signal to be measured in its place. Subsequent
readings will be the difference between the stored value
and the applied signal.
2-10
1. Disabling zero cancels the zero baseline value on that
selected function. However, since the zero value is
automatically stored in Program ZERO, the zero
baseline value can be retrieved by using the program
as long as the ZERO button is not again pressed (see
paragraph 2.8.5 for details). Pressing the ZERO button,
thus enabling zero, will wipe out the previous baseline
value in Program ZERO. Baselines established on other
functions are not affected.
2. To store a new baseline on a selected function, zero
must first be disabled and then enabled again. The new
value will be stored with the first triggered conversion.
The baseline value will also be stored as the zero value
in program ZERO, cancelling the previously stored
value.
3. Setting the range lower than the suppressed value will
overrange the display; the instrument will display the
overrange message under these conditions.
4. When the ZERO button is pressed to enable zero, the
zero indicator light will blink until an on scale reading
is available to use as a zero level.
OPERATION
filter value. For example, for a filter value if IO, one time
constant is equal to 10 readings and three time constants
would be equal to 30 readings. ‘The blinking duration
will be shorter in the 31id mode since th.at has the fast<zst
reading rate.
3. In a continuous trigger mode, a reading that is <,utsidc
the filter window will cause the filter indicator t<l blink
for one time constant.
Digital Filter-The Model 193 utilizrs ‘1 digit,11 filter tij ate
tenuate excess noise present on input signals. The filter
is a weighted average type. The mathematical rcprewn
tation is:
(new reading -AVG(t ~I))
AVG(t) = AVG(t-1) + ~.
r:
Where,
AVG(t) = displayed average
AVG(t - ‘I) = old displayed average
F = weighting factor (filter value)
2.6.3 Filter
When the filter is enabled, a number of measurements are
averaged before being displayed. The factory default
number is 10, but it can be changed to a value from 1
to 99 with the use of the FILTER program. A filter value
can be set for any or all measurement functions and is
remembered by each function. For example, a filter value
of 20 can be set for DCV and a filter value of 55 can be
set for ACV. These filter values will not be cancelled by
switching back and forth between functions.
An advantage of using the filter is to stabilize the reading
of a noisy input level. A consideration of filter usage is
that the larger the number of readings averaged, the
longer the response time of the display. Perform the
following procedure to use the filter:
1. If it is desired to check and/or change the filter value,
utilize Program FILTER as explained in paragraph 2.8.6.
2. Press the FILTER button. The FILTER indicator will turn
0”.
Notes:
1. Pressing the FILTER button a second time will disable
the filter.
2. After a reading is triggered (continuous or one-shot),
the filter indicator light will blink for three time constants. A time constant is measured in readings. The
number of readings in one time constant is equal to the
As with any filter, the Model 193 digital filter will affect
reading response time. The step response for this filter
is of the form:
step response = I- K(“+ ‘)
Where,
“K” is a constant based on the filter \veighting fact<>1
“n” is the reading number.
The step occurs ~‘hen n =O. II = 1 is th? first reading dftcr
the step, n=2 is the second reading, etc.
Therefore:
step response = 1 -
Example:
F = ‘IO
n=s
2.11
Loading...