Keithley 199

SECTION 5-Principles of Operation
5.1
INTRODUCTION . . . .._......__._ >.,i_<~r...~ ___r..... 1,__ . . . . . . . . . . . . ..____._..~...... a,>_,,y __,. ;:i~;l,:~;~i~5.1
5.2
OVERALLFUNCTIONALDESCRII’TION ___......_....._... _ .I-., _,_.._.__.__ .__.._. _ .___.. I,_.~.._.,.
5.1
5.3
ANALOG CIRCUITRY.. . _. ..__I __-_ __~_~A __~_I_.. _. _ _ ..,. ii,_,. .~_ _ z _. . :.‘I-. _. _ .~.,. _. 5-l
5.3-l
InputSignalConditioning .._.. .._._. _~_I ,._._ 1 . . . . . . ~,I ..-.-. i_i~ . . . . . i _.._ ;.)I’..;~.:.’ _.._ i_i_.
5-1
5.32 Multiplexer
. ~5-6
5.3.3
-28V Reference Source . ~. . ~. : .~. : ;.::~. . . . . _ .,-._
/ . . . . iii _........__ r.‘.;. ______^___ ~_iii_~ ____
~5.8
513.4~~~
InputBufferAmplifier . . . . . . !.~.I ..____..... _ ..,.......... 2 . . . . . . . . i . . . . . ..__....____ ~_i.,_,.. 5-8
5.4
A/D CONVERTER
.._.....,_. __._,_,_. _~_.~._._~______~..,_ _~.......___....._.___. ..__ ____ ____ i...:.....1=~~5-8
5.5
~~~:CONTROLCIRCUITRY ~.~.~.,.<..;z .__....__. > ,...-,.... i.i..~...~._ . . . . . . . . . . :..:..i~ . .._.... ‘1.
5-10
5.6 : DIGITALCIRCUITRY .__.____tt__ ::w..~.-. _____,_.: ___,_. _ ,_..______,_ ~ .~_.~______ L ._t____...; ____._,,. ;v_._ 5-10
5.6.1
Microcomputer . . . .._.._.._..____... ~_~i__,ij .,_. Ijj,__,,j’ . . . . . . . . . . l_-~._..;_;..: . . . . . . . . z..:;..;..;...
5-10
5.6.2
Display Circuitry . ; _ _ -1-i ,“.., I . . . .._. _ ___,_ _ , . . :-.: .;~.-- _. .~_~_ j~l~_l, ;. .~_ .‘+z.. .:: :. . . .,. &lO
5.7
POWERSUI’I’LIES _.,__..; .__.__ :..~:.. ._...___ __.. I).~ .._._._ -~.~.-..I...:..;..~ __._.I :._.i _,,.._.__ ~5-IC
5.8 SCANNER . . . . . . . . . .._.._.....~..... ~ ,_______. _...,. L . . .._.-__I_.._, _.I ._..._.... 2 .._...._..__..... 5-10
58.1
c0ntr01cicnilTy . . . . . . . . . ..___. _... -.~..~~-;.~.~-~~,~...~ ,........ ~_.~.i ~....___.....____.. ..,_ _ . . . . . . . .
5-10
5.8.2
Switching Relays . . . . I. _ . _ a~.~. .z: __. i,. i.i. ._ _ . _.i .~:; . i: . . . . I._. _ ) ;~: .~xr:~. . _. . S-11
SECTION 6-Maintenance
6.1
INTRODUCTION
................ .t......_
... __., i ,a,_ :i..> .: ..i.:.;; .. _‘i .... ._I’., ..:.... L.‘:.-,:,-:-~
....... 6-l
6.2
LINEVOLTAGESELECTION
.............
..I: ... . ............ ._ .............
i;. .,_,_, -.----T.i~...-..L~~ ..- 6-1
6.3
FUSEREPLACEMENT
.......... ~.,.-.; ._ 1.;
..... ;...:.~..:..A:.1 ............ l,i~irl_ii_,i,i.~.ii_._‘_1.
.... ~61
6.3.1
LineFuse ....................... . ..-L......i.~~..............~:~~~:
..... ;~_; .,._ ... . ..
..~~....~..~..11.... ........... 6-1
6.3.2
Current FU
se ..................... L .......................
.._ .. i ._.__ f.. ... _ ...............
_i ....... 6-2
6.4
CALIBRATION
............. _^__ .. .~.I;~._.~
........ _._ _ ......... ;: : ........... I..:.
....... c. -.-:.‘:a; .... 1~: .... 6-2
6.4.1
Recommended Calibration Equipment
...........
;. : ... __ ........ . ........ _,.;, ___
........................ 6-2
6.4.2
Environmental Conditions
...
:
.
.~; :~.~:::~I.
..
._ _ .~i,l.Lj.l .
._
......................
; :. ; __:
.......
:
......
:~ 6-3
6.4.3 ..
Warm-UpPeriod.. ......................
:_ili.. .. ~.i. ... . ................................
.: ............. 6-3
6.4.4
CAL Lock Switch .............. ,.,_ _, _ L ., _
... _yy_~I _ jmj.i .... i .. j i~i ..* :.. _ ....~..~.L~...~. ... i
.. _ _ -‘: ;.r: .z: : . : . ; ..... 6-3
6.4.5
Front Panel Calibration ............ ...._:
......... . . ... .
.....
.
..
::.
.....
I
..............................
6-3
6.4.6
IEEE-488 Bus Calibration
...........................
.
...............
:.
..
.~.+ ;.. ....
.*.
............
6-4
6.41
Calibration Sequence .....................
._ ................. _. ..... .,,_ ,, ....
_
..
, _._ .. _,_ .; L __ : .. ‘L #,,., jl, 6-5
6.4.8
DCVoltsCalibration..
........................
_ . .._
.....
,__L.__~. ..... ..~.....‘....‘~~~.i.‘.~.......‘.:.’.:’.~..l. 6-5
6.4.9
Resistance C&&ration ....................
_ ............ . pi .~i i.
..
i:.
......................
., _:_ ...... _~;
.
; 6-6
6.4.10
TRMSACVoltsCalibration ...... ........
L.. .. l.. ................ ....t...ii ..__ _. ..;: ....... _ ....... _ 2,
6-8
6.& DCC
unrent Calibration ......... ~.,~“~.-~ ........
. .................. __,_._______
..... .:..~ ........... 6-12
6.5.
TRMS AC Current Calibration ...........
_ .............. i _.__ .._._. _,.,_ .. _~.,:
......... .,_ ...... ..; .... 1’: 6-12
DISASSEMBLY INSTRUCTIONS..
.............................
+ ........... . ..................
L.. .. ~...6- I3
6.6 SPECIAL HANDLING
............................
__._ ......... ~.~..6-17.
6.7 TROUBLESHOOTING
................
.~:~I
.......
._I,, _
....
._,__ _._i~_.i_.
....
..i
....
L
... ii :..::z:.:
.............
I 6-v
67.1
Recommended Test Equipment ..................
,_.,_ ............
Il~_~_~.~i
.....
i_
.....
i
....
_‘*._ _‘wr~_:_ ~6-17
6.7.2 ..
I’owerUpSeIfTest ............. _.._. _._--,.L~.i.~~__~~i,.~
.... ..^ ._ i ........ ;..e_
.._._; _ ...... ~;.;....~6- 17
6.7.3
Diagnostics ............ .._.__ .....................
_. ... ..___ _ i.__._-__.iz~
. ..__ .. -..;..~.:.~..:. 6-l8
6.%4
PowerStipplies.. ....................
_.____.^ .~.........._. .: .__, L___ .... __I
..... .._ ............ 6-18
6.7.5
Signal Conditioning Checks ............ _ _ ....... . .-
....
~=.;. ..... _
............................
..L. _._
...........
6-18
6.76
DigitalandDisplayCircuitryChecks..
..... _._ .... ji,. .............................
. ___._._.__._ 6-18
6.7.7
Scanner Checks.. .............. .~...~__.__ _ _
..... ____., i _.___ __w,i_~/.
................
.___.__ ii._i,_i_i 6-18
6.8 ~SCANNERINSTALLATIONANDCHECKOUT.
........
_..i.....l.i.....l.._i_ i .....
.._. izi,.__ ...... .._
..
6-22
6.8.1
Installation .......................... _ ............
.___ ,i .......... .._.
.....
;.: ._. ......
.;-
...........
6-22
6.8.2
Card Checkout .....................................................
_._& ..................
i ......... 6-23
6.8.3
Relay Shield Jumper ..................
.
............
_.
............
_,_ ...... .__ ___ .
_._.
........
; .... 6-24
iv