Keithley 7058 Service manual
Model 7058 low Current Scanner
Plug-In Card
Instruction Manual
Contains Operating and Servicing Information
Model 7058 Low Current Scanner
Plug-In Card
Instruction Manual
0 1991, Keithley Instruments, Inc.
Test Instrumentation Group
All rights reserved.
Cleveland, Ohio, U.S.A.
October 1991, Second Printing
Document Number: 7058-901-01 Rev. B
Safety Precautions
The following safety precautioos should be obsewed before using this product and any asnociated instrumcntatioo. Although some inrtromeots and accessories woold nonnally bo used
with nowhazardous voltages, there arc situations wberc hazardous conditions may be present.
This product is intended for use by qualified personnel who rccogoiu: shock hazards and are
familiar with tbc safety pnxaotions rcqoircd to avoid possible injuly. Read lbe operating it]formation carefully before using the product.
‘The types of product users arc:
Kesponsiblc body is tbe iodividunl or group responsible for the USC sod owinleoaoce of
equipment, for ensuring tlnt the equipment ia operated within its spccilications and operating limits, and for ensuring that operators are adequately trained.
Operators use the product for its intended function. Tbey most be trained in electrical safety
procedures and proper use of the iostrument. ‘lhey most be protected from electric shock and
~onmt with hazardous live circuits.
Maintenance personnel perform mutioe procedures oo the product to keep it operadog, for
example, setting the hoc voltage or replacing consumable materials. Maintenance proccdurcs
am dcacribed in the manual. The procedures explicitly state if the operator ~nay perform them.
Othcrwisc, they should be performed only by senice pcnonoel.
Service personnel are trained to work on live circuits, sod perfoonn safe installations sod repairs of products. Ooly properly trained setvice personocl may perform installation and scrvice procedures.
Exercise extreme caution whco a shock hazard is present. Lethal voltage may be present on
cable coonector jacks or test fixtures. 111~ American National Standards lostitute (ANSI)
stam that a shock hazard exists wheo voltage levels greater than 30V RMS, 42.4V peak, or
60VDC are present. A good safety practice is to expect that hazardous voltage is present
in any unknown circuit before measuring.
Users of this product must be protected fmm electric shock at all timer. The responsible body
must eosum thtat wets aw pwented a.cce~s aod/orinsulatcd from every connection point. lo some
cases, conoectiuns most be exposed to potential buman cootact. Product usa io these circuostances must be trained to protect themselves from the risk of electric shock. If the circuit is capable of operating at or abovc 1wO volts, no conductive part of the circuit may be exposed.
AY described in the Ioteroational Electratechnical Commission (IEC) Standard IEC 664, digital multimcter measuring circuits (e.g., Keifhley Models 175A, 199, 2OOQ,2COl, 2002, and
2010) are Installation Category II. All other instruments signal tennioals are Installation Category I and must oat be conoected to mains.
Do not conoect switching cards directly to unlimited power circuits. They are inlendcd to bc
used with impedance limited sources. NEVER connect switching cards directly to AC mains.
Wheo conoccting sources to switching cards. iostall protective devices to limit fault current
sod voltage to tbc card.
Before operating ao instrument, make sure the line cord is connected to a properly grounded
power receptacle. Inspect the connecting cables, test leads, and jumpers for possible wear,
cracks, or breaks bcforc each oso.
For maximum safety, do not touch the product, test cables, or any other instrumcots while power is applied to the circuit under test. ALWAYS remove power from the entire test system sod
dischuge soy capxitors before: coooccting or disconnecting cables or jumpers, installing 01
removing switching cards. or making iotemtil chaogcs, socb as installing or nzmoviog jumpers.
Vu not touch soy object that could provide a con-cot path to tbc common side of the circuit
under test or power line (eatth) ground. Always make measurements witb dry hands while
standing oo a dly, insulated surface capable of withstanding tbc voltage bciog measured.
The instrument and accessories most be used in accordance with its specifications and operatiog iostructioos or tbe safety of the equipment may be impaired.
Do not exceed the maximum signal levels of the instruments and accessories. as defined in
tbe speciticationr sod operatiog information, and es show on the instrument or test fixture
panels, or switcbiog cant.
When fores are used in a product, replace with same type sod rntiog forcootioued pmtectioo
against fire hazard.
Cbassir connections must only be used as shield coooectioos for me~suriog circoits, NOT as
safety eaflh ground connections.
If you are using II test fixture, keep the lid closed while power is applied to the device under
test. Safe operation requires tbe we of a lid interlock.
1ra@
screw is present, connect it to safety earth ground uaiog the wire recommended in
the user documentation.
The ! symbol on an iostroment indicates that the user should refer to the operating ill-
n
stmctions located io tbc manual.
The h
symbol on al iostmment shows that it CNI source or IIICRIIUII: loo0 volts or more, illeluding the combined etTect of normal ad common mode voltages. Use stiuldarrl safety precaulions to avoid pcrsooal cootect with these voltages.
TIE WARNING beading in A manual enplaios dangers that might result in personal injury or
death. Always read the associated information wy carefully hcfore ptxformiog the indicated
pC"CCdU~C.
The CAUTION beading in a manual explains hazards that could damage the instrument.
Such damage may invalidate the warrmty.
lostrumcntatioo and accessories shall not be connected to humans.
Before performing any maintenance, disconnect the line cord and all test cables.
To maintain pmtcctioo from electric shock and ftre, replacement components in mains circoils, including the power transfouner, test leads, and ioput jacks, must he purchased from
Keithley Instruments. Standard fuses, with applicable national safety appmvals, may be used
if the ratiog sod type are the same. Other components that are not safety r&ted may hc por-
chased from other suppliers as long as they are equivalent to tbe original component. (Note
that selected parts should be purchased only through Keithley Iostmmcnts to maiotain accoracy sod fonctiooality of the product.) If you we unsure about the applicability of a replaccment component, call a Keithlcy Instruments office for information.
To clean an instrument. use a damp cloth or mild, water based cleaner. Clean the exterior
of the instrument only. Do not apply cleaner directly tb the instrument or allow liquids to
enter or spill on the instrument. Products that consist of a circuit hoard with no case or cbassis (e.g., data acquisition board for installation into a computer) should neverrequire cleaning if handled according to instructiuns. If the board becomes contaminated sod operation
is affected. the hoard should he returned to the factory for proper cleaninglserviciog.
tie”. 2rB
SPECIFICATIONS
7058 LOW CURRENT SCANNER CARD
CHANNELS PER CARD: 10.
CONTACT CONFIGURATION: Single pole. break-before-make for signal
HI in ut. Signal LO is mmmon for all 10 channelr. When ., channel is off.
signa P HI IS connected to signal LO through an internal jumper.
CONNECTOR TT’E: Triaxial.
RELAY DRIVE CURRENT: 24mA per relay typical.
SIGNAL LEVEL: 28”. lOOmA maximum (non-inductive load only).
CONTACT LIFE: >I@ ~losum at maximum signal le~ek
CONTACT RESISTANCE: c ,R to rated life.
CONTACT POTENTIAL: < &QJ”.
ACTUATION TIME: < 15,~ exclwive of mainframe.
CHANNEL ISOLATION: >10”R. <O.lpF with internal jumper removed.
INPUT ISOLATION: >KPn. <SOpF.
OFFSET CURRENT: < ,@“A t < ,@“A typical).
COMMON MODE VOLTAGE: <X.3” peak.
GENERAL
OPERATING ENWRONMEM: 0” 10 50°C. up lo 35°C at 70% RH.
STORAGE ENVIRONMENT: -25°C lo 65°C.
DIMENSIONS, WEIGHT: 32mm high X 114mm wide
X 4%” X 10%“~. Net weight 0.54kS (19 oz.).
ACCESSORIES AVAILABLE:
Model 7024-3 Triaxial Cable, O.Pm (3 ft.)
Model 7024-S Triaxial Cable. 1.5m (5 ft.)
x
BBCBUSB of the high impedance of the board spatial care should be
taken in both handling and using the board to prevent degradation of
performance. Handle the board only by the edges when using it and
keep the bawd free of body oils. dirt and contaminants. To clean the
board use Freor6
or soft brush. Care should be taken to ensure that the solvent is not
contaminated before wing it on the board. After the solvent has been
applied blow dry the board with dry nitrogen gas.
TMS or TE or equivalent and a clean Norton swab
NOTE
TABLE OF CONTENTS
SECTION l-GENERAL INFORMATION
Introduction ............................................
1.1
Warranty Information
1.2
ManualAddenda
1.3
SECTION Z-OPERATION
2.1 Introduction ............................................
2.2 Wiring and Installation ....................................
Operating Considerations .................................
2.3
2.3.1
2.4
3.1
3.2
3.3
3.4
4.1
4.2
4.3
4.4
4.5
Limits on Switching SDeed ...............................
Model7058 Modification
SECTION 3-SERVICING INFORMATION
Introduction ............................................
Handling Instructions
TestEquipment
PerformanceVerification
SECTION I-REPLACEABLE PARTS
Introduction ............................................
ReplaceablePans ........................................
Ordering Information .....................................
FactoryService ..........................................
Component Layout and Schematic Diagram .................
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LIST OF FIGURES
1
Typical Multi-Scanner Connection.
2
Typical Switching Circuit For Model 7058
3
Jumper Modlficatlon ......................................
4
Test Set Up for Offset Current Test
Test Set Up for Signal Path Resistance Test.
5
6
Test Set Up for Shunt Impedance Test
Test Set Up for Relay Timing Test
Channel Isolation Test
i
9
Model 7058 Component Location Drawing
10
Model 708 Schematic Diagram
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3
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4
4
5
7
7
8
13
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3
4
5
9
9
9
lo
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14
16
1
Recommended Test Equipment,,
2
Model 7058 Replaceable Parts List
LIST OF TABLES
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12
13
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