Keithley Instruments, Inc. warrants this product to be free from defects in material and workmanship for a
period of 1 year from date of shipment.
Keithley Instruments, Inc. warrants the following items for 90 days from the date of shipment: probes, cables,
rechargeable batteries, diskettes, and documentation.
During the warranty period, we will, at our option, either repair or replace any product that proves to be defective.
To exercise this warranty, write or call your local Keithley representative, or contact Keithley headquarters in
Cleveland, Ohio. You will be given prompt assistance and return instructions. Send the product, transportation
prepaid, to the indicated service facility . Repairs will be made and the product returned, transportation prepaid.
Repaired or replaced products are warranted for the balance of the original warranty period, or at least 90 days.
LIMIT A TION OF W ARRANTY
This warranty does not apply to defects resulting from product modification without Keithley’s express written
consent, or misuse of any product or part. This warranty also does not apply to fuses, software, non-rechargeable batteries, damage from battery leakage, or problems arising from normal wear or failure to follow instructions.
THIS WARRANTY IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESSED OR IMPLIED, INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE.
THE REMEDIES PROVIDED HEREIN ARE BUYER’S SOLE AND EXCLUSIVE REMEDIES.
NEITHER KEITHLEY INSTRUMENTS, INC. NOR ANY OF ITS EMPLOYEES SHALL BE LIABLE FOR
ANY DIRECT , INDIRECT, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF
THE USE OF ITS INSTRUMENTS AND SOFTWARE EVEN IF KEITHLEY INSTRUMENTS, INC., HAS
BEEN ADVISED IN ADVANCE OF THE POSSIBILITY OF SUCH DAMAGES. SUCH EXCLUDED DAMAGES SHALL INCLUDE, BUT ARE NOT LIMITED TO: COSTS OF REMOVAL AND INSTALLATION,
LOSSES SUSTAINED AS THE RESULT OF INJURY TO ANY PERSON, OR DAMAGE TO PROPERTY.ERTY.
The print history shown below lists the printing dates of all Revisions and Addenda created
for this manual. The Revision Le vel letter increases alphabetically as the manual under goes subsequent updates. Addenda, which are released between Revisions, contain important change information that the user should incorporate immediately into the manual. Addenda are numbered
sequentially . When a new Re vision is created, all Addenda associated with the previous Re vision
of the manual are incorporated into the new Revision of the manual. Each ne w Revision includes
a revised copy of this print history page.
Revision A (Document Number 7999-5-901-01).....................................................November 1999
Revision B (Document Number 7999-5-901-01)..................................................... December 1999
All Keithley product names are trademarks or registered trademarks of Keithley Instruments, Inc.
Other brand names are trademarks or registered trademarks of their respective holders.
Safety Precautions
The following safety precautions should be observed before using this product and any associated instrumentation. Although some instruments and accessories would normally be used with non-hazardous
voltages, there are situations where hazardous conditions may be present.
This product is intended for use by qualified personnel who recognize shock hazards and are familiar
with the safety precautions required to avoid possible injury. Read the operating information carefully
before using the product.
The types of product users are:
Responsible body
ensuring that the equipment is operated within its specifications and operating limits, and for ensuring
that operators are adequately trained.
Operators
and proper use of the instrument. They must be protected from electric shock and contact with hazardous
live circuits.
Maintenance personnel
setting the line voltage or replacing consumable materials. Maintenance procedures are described in the
manual. The procedures explicitly state if the operator may perform them. Otherwise, they should be
performed only by service personnel.
Service personnel
ucts. Only properly trained service personnel may perform installation and service procedures.
Exercise extreme caution when a shock hazard is present. Lethal voltage may be present on cable con-
nector jacks or test fixtures. The American National Standards Institute (ANSI) states that a shock hazard exists when voltage lev els greater than 30V RMS, 42.4V peak, or 60VDC are present.
practice is to expect that hazardous voltage is present in any unknown circuit before measuring.
Users of this product must be protected from electric shock at all times. The responsible body must ensure that users are prevented access and/or insulated from every connection point. In some cases, connections must be exposed to potential human contact. Product users in these circumstances must be
trained to protect themselves from the risk of electric shock. If the circuit is capable of operating at or
above 1000 volts,
As described in the International Electrotechnical Commission (IEC) Standard IEC 664, digital multimeter measuring circuits (e.g., Keithley Models 175A, 199, 2000, 2001, 2002, and 2010) are Installation
Category II. All other instruments’ signal terminals are Installation Category I and must not be connected to mains.
Do not connect switching cards directly to unlimited power circuits. They are intended to be used with
impedance limited sources. NEVER connect switching cards directly to AC mains. When connecting
sources to switching cards, install protective devices to limit fault current and voltage to the card.
Before operating an 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 before each use.
For maximum safety, do not touch the product, test cables, or any other instruments while power is applied to the circuit under test. ALWAYS remove power from the entire test system and discharge any
capacitors before: connecting or disconnecting cables or jumpers, installing or removing switching
cards, or making internal changes, such as installing or removing jumpers.
is the individual or group responsible for the use and maintenance of equipment, for
use the product for its intended function. They must be trained in electrical safety procedures
are trained to work on live circuits, and perform safe installations and repairs of prod-
no conductive part of the circuit may be exposed.
perform routine procedures on the product to keep it operating, for example,
A good safety
Do not touch any object that could provide a current path to the common side of the circuit under test or power
line (earth) ground. Alw ays make measurements with dry hands while standing on a dry, insulated surface capable of withstanding the voltage being measured.
The instrument and accessories must be used in accordance with its specifications and operating instructions
or the safety of the equipment may be impaired.
Do not exceed the maximum signal levels of the instruments and accessories, as defined in the specifications
and operating information, and as shown on the instrument or test fixture panels, or switching card.
When fuses are used in a product, replace with same type and rating for continued protection against fire hazard.
Chassis connections must only be used as shield connections for measuring circuits, NOT as safety earth
ground connections.
If you are using a test fixture, keep the lid closed while power is applied to the device under test. Safe operation
requires the use of a lid interlock.
If a screw is present, connect it to safety earth ground using the wire recommended in the user documentation.
!
The symbol on an instrument indicates that the user should refer to the operating instructions located in
the manual.
The symbol on an instrument sho ws that it can source or measure 1000 volts or more, including the combined effect of normal and common mode voltages. Use standard safety precautions to av oid personal contact
with these voltages.
The
WARNING
read the associated information very carefully before performing the indicated procedure.
heading in a manual explains dangers that might result in personal injury or death. Always
The
CAUTION
invalidate the warranty.
Instrumentation and accessories shall not be connected to humans.
Before performing any maintenance, disconnect the line cord and all test cables.
To maintain protection from electric shock and fire, replacement components in mains circuits, including the
power transformer, test leads, and input jacks, must be purchased from Keithley Instruments. Standard fuses,
with applicable national safety approvals, may be used if the rating and type are the same. Other components
that are not safety related may be purchased from other suppliers as long as they are equivalent to the original
component. (Note that selected parts should be purchased only through Keithley Instruments to maintain accuracy and functionality of the product.) If you are unsure about the applicability of a replacement component,
call a Keithley 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 to the instrument or allow liquids to enter or spill on the instrument. Products that consist of a circuit board with no case or chassis (e.g., data acquisition board for installation into a
computer) should never require cleaning if handled according to instructions. If the board becomes contaminated and operation is affected, the board should be returned to the factory for proper cleaning/servicing.
heading in a manual explains hazards that could damage the instrument. Such damage may
Rev. 10/99
Model 7999-5 Specifications
OUTPUTS: 16 open collector relay control lines, each capable of 300mA max. sink current. Coil suppression diodes included.
OUTPUT SATURATION VOLTAGE: 0.18V typ. @ 300mA.
MAXIMUM RELAYPOWER VOLTAGE: 28V DC (user supplied).
CONNECTORS: Two 10-position quick disconnect terminal blocks.
UPPER CONNECTOR: Relay power, relay common, relay control outputs 1–8.
LOWER CONNECTOR: Relay power, relay common, relay control outputs 9–16.
The relay common of the upper and lower connectors is internally connected together to chassis ground.
The relay power inputs of the upper and lower connectors are separate, allowing two different coil voltages to be used for each bank.
GENERAL
INTERFACE: RS-232 control (9600 baud, 8 data, 1 stop). Response terminator selectable (CR, LF, CRLF, LFCR).
ENVIRONMENT: Operating: 0° to 40°C, up to 35°C <80% RH. Storage: –25° to 65°C.
POWER CONSUMPTION: 7.3W.
WARRANTY: 1 year.
EMC: Conforms with European Union Directive 89/336/EEC, FCC part 15 class B.
SAFETY:Conforms with European Union Directive 73/23/EEC.
DIMENSIONS: 109mm long × 112mm wide × 59mm deep (4.3˝ × 4.4˝ × 2.3˝).
ACCESSORIES SUPPLIED: AC/DC power adapter (100–120VAC/ 220–240VAC, 50 or 60Hz) with line cord, user and service manual, two terminal
Table 5-2Parts list—mechanical parts ................................................... 5-4
1
General Information
1-2General Information
Introduction
This section contains general information about the Model 7999-5 16-channel RS-232 relay
controller. The information is organized as follows:
•Feature overview
•Warranty information
•Manual addenda
•Safety symbols and terms
•Specifications
•Unpacking and inspection
•Connections
If you have any questions after reviewing this information, please contact your local
Keithley representative or call a Keithley Applications Engineer at 1-800-348-3735 (U.S. and
Canada only). Worldwide phone numbers are listed at the front of this manual.
Feature overview
The Model 7999-5 is a 16-channel open collector relay controller with the following
features:
•16 open-collector relay control lines
•Quick-disconnect terminal block type connectors (mating connectors supplied)
•Coil suppression diodes
W arranty information
Warranty information is located at the front of this instruction manual. Should your Model
7999-5 require warranty service, contact the Keithley representative or authorized repair facility in your area for further information. When returning the relay controller for repair, be sure
to fill out and include the service form at the back of this manual to provide the repair facility
with the necessary information.
Manual addenda
Any improvements or changes concerning the relay controller or manual will be explained
in an addendum included with the manual. Be sure to note these changes and incorporate them
into the manual.
Safety symbols and terms
The following symbols and terms may be found on the relay controller or used in this
manual.
Thesymbol indicates that the user should refer to the operating instructions located in
!
the manual.
General Information1-3
The
symbol
safety precautions to avoid personal contact with these voltages.
The
WARNING
injury or death. Always read the associated information very carefully before performing the
indicated procedure.
The
CAUTION
controller. Such damage may invalidate the warranty.
shows that high voltage may be present on the terminal(s). Use standard
heading used in this manual explains dangers that might result in personal
heading used in this manual explains hazards that could damage the relay
Specifications
Full Model 7999-5 specifications are included at the front of this manual.
Unpacking and inspection
Inspection for damage
The Model 7999-5 is packaged in a re-sealable, anti-static bag to protect it from damage due
to static discharge and from contamination that could degrade its performance. Before removing the relay controller from the bag, observe the precautions on handling discussed below.
Handling precautions
•Always grasp the relay controller by the covers. Do not touch board surfaces or
components.
•After removing the relay controller from its anti-static bag, inspect it for any obvious
signs of physical damage. Report any such damage to the shipping agent immediately.
•When the relay controller is not installed and connected, keep the relay controller in its
anti-static bag, and store it in the original packing carton.
1-4General Information
Shipment contents
The following items are included with every Model 7999-5 order:
•Model 7999-5 16-channel relay controller
•PS-57A Power supply module (AC/DC converter 100-240VAC to 12VDC, IEC AC
inlet)
•Two 10-pin terminal block mating connectors
•Model 7999-5 Instruction Manual (this manual)
•Additional accessories as ordered
Instruction manual
If an additional Model 7999-5 Instruction Manual is required, order the manual package,
Keithley part number 7999-5-901-00. The manual package includes an instruction manual and
any pertinent addenda.
Repacking for shipment
Should it become necessary to return the Model 7999-5 for repair, carefully pack the unit in
its original packing carton or the equivalent, and include the following information:
•Call the Repair Department at 1-888-KEITHLEY for a Return Material Authorization
•Advise as to the warranty status of the relay controller.
•Write ATTENTION REPAIR DEPARTMENT and the RMA number on the shipping
•Fill out and include the service form located at the back of this manual.
Connections
The following are available Model 7999-5 connections:
•Two 10-position quick-disconnect connectors
•Power receptacle: 3-pin phoenix jack for supplied power module
•RS-232 port: DB-9 connector
NOTE
(RMA) number.
label.
Refer to Section 2 for detailed connection information.
2
Connections
2-2Connections
Introduction
This section contains information about overall relay controller configuration and connections and is organized as follows:
•Handling precautions
•Configuration
•Connections
Handling precautions
Care should be taken when handling the relay controller to avoid contamination from such
foreign materials as body oils. Such contamination can reduce isolation resistance. To avoid
possible contamination:
•Always grasp the relay controller by the case.
•Do not touch connector insulators.
•Operate the relay controller in a clean environment. If the relay controller becomes contaminated, it should be thoroughly cleaned as explained in Section 4.
Connections2-3
Configuration
Layout
Figure 2-1 shows the general layout of the Model 7999-5 which features:
Connectors:
•Power receptacle: 3-pin phoenix jack for supplied power module
•RS-232 port: DB-9 connector
•Two 10-pin quick disconnect connectors
Indicators:
•Power LED
Figure 2-1
General layout
2-4Connections
Connections
RS-232 connection
The RS-232 serial port is connected to the serial port of a computer (controller) using a
straight-through RS-232 cable terminated with DB-9 connectors. Do not use a null modem
cable. The serial port uses the transmit (TXD), receive (RXD), and signal ground (GND) line
of the RS-232 standard. Figure 2-2 shows the Model 7999-5 connector with Table 2-1 containing the pinouts for the connector.
If your computer uses a DB-25 connector for the RS-232 interface, an additional cable or
adapter (DB-25 to DB-9) is required.
NOTEIn the RS-232 interface, only pins 2, 3, and 5 are used. Pins 7 and 8 are tied together ,
Table 2-1
RS-232 connector terminals
but not connected to the circuit board. Pins 1, 4, and 6 are also tied together and not
connected to the circuit board.
Pin numberDescription
1
2
3
4
5
6
7
8
9
Figure 2-2
RS-232 interface connector
Tied to pins 4 and 6
TXD, Transmit data
RXD, Receive data
Tied to pins 1 and 6
GND, Signal ground
Tied to pins 1 and 4
Tied to pin 8
Tied to pin 7
Not used
RS232
5 4 3 2 1
9 8 7 6
Power connector
Connect the supplied power adapter (Model PS-57A) to the power connector.
CAUTIONTo prevent damage to the Model 7999-5, use only the Keithley Model PS-
57A AC/DC power adapter. This is a universal input (100V-240VAC,
50/60Hz), 12VDC output (3A or less) supply.
Quick disconnect connections
CAUTIONEach relay control line is capable of sinking up to a maximum of 300mA
with the maximum relay power voltage of 28VDC.
Two 10-position quick disconnect terminal blocks provide for relay control connections.
The upper connector is for relay control outputs 1–8, while the lower connector is for relay
control outputs 9–16. The relay common of both the upper and lower connector are connected
to chassis ground while the power connections for each connector are separate. The control
outputs are protected by coil suppression diodes (suppresses voltage spikes when relay coil is
de-energized). Refer to Table 2-2, Table 2-3, and Figure 2-3 for connector pinouts.
Connections2-5
Table 2-2
Upper relay connector pinouts
Pin numberDescription
1
2
3
4
5
6
7
8
9
10
Relay power connection
Relay control output 1
Relay control output 2
Relay control output 3
Relay control output 4
Relay control output 5
Relay control output 6
Relay control output 7
Relay control output 8
Chassis ground connection
2-6Connections
Table 2-3
Lower relay connector pinouts
Pin numberDescription
Figure 2-3
Relay control
connector pinouts
10
1
2
3
4
5
6
7
8
9
Relay power connection
Relay control output 16
Relay control output 15
Relay control output 14
Relay control output 13
Relay control output 12
Relay control output 11
Relay control output 10
Relay control output 9
Chassis ground connection
Relay
Control
87654321
Relay
Common
9 10111213141516
Relay
Control
Relay
Power
3
Operation
3-2Operation
Introduction
This section contains operating information for the Model 7999-5. The information is orga-
nized as follows:
•Maximum voltage and current considerations
•Operation (RS-232)
Maximum voltage and current considerations
WARNING
CAUTION
Maximum voltage between any conductor and ground is 42V.
T o prevent damage to the Model 7999-5, do not exceed the following maximum specifications:
•
•
Operation (RS-232)
Sending and receiving data
The Model 7999-5 relay controller is RS-232 controlled. Before the relays can be controlled, connect an appropriate and properly configured controller to the DB-9 port. The Model
7999-5 serial interface (RS-232) transfers data using eight data bits, no parity, and one stop bit
(8-N-1). The interface also transfers data at 9600 baud. Make sure that the controller selected
also uses these settings.
The relay controller can provide one of four different termination characters to the RS-232
controller (see “Termination characters”). The relay controller can receive any valid termination character sent by the RS-232 controller (line feed and/or carriage return).
T ermination characters
Maximum relay coil voltage: 28VDC
Maximum current: 300mA maximum sink current per relay
The Model 7999-5 can be configured to terminate each program message transmitted to the
controller with any of the following combinations of <CR> or <LF>:
<CR>Carriage return (factory default setting)
<CR+LF> Carriage return and line feed
<LF>Line feed
<LF+CR> Line feed and carriage return
Operation3-3
To configure the termination character, change the jumpers for PA6 (J1006) and PA7
(J1008) located on the Model 7999-5 printed circuit board. Refer to Figure 3-1 and Table 3-1
for jumper details. Refer to the first three steps of disassembly information in Section 4 to
access the circuit board.
Figure 3-1
Jumper location
NOTE
Changing the jumper settings sets the termination characters sent by the Model
7999-5 to the RS-232 controller. Any valid termination character sent by the RS-232
controller can be received by the Model 7999-5 (line feed and/or carriage
return).The send and receive termination characters do not have to match.
1
1
Table 3-1
Jumper positions—termination characters
TerminatorJ1006 pinsJ1008 pins
1
<CR>
<CR+LF>
<LF>
<LF+CR>
1
Factory default setting
1 and 2
2 and 3
1 and 2
2 and 3
1
1 and 2
1 and 2
2 and 3
2 and 3
1
3-4Operation
RS-232 command set
NOTE
Table 3-2
Command set
ASCII Command Parameter TypeDescription
A or aNoneOpens all relays. After all relays are opened and the delay occurs
C or c<list>Closes specified relay(s). After this command is sent and a termina-
D or d<delay>Sets the variable relay settling time (delay) in milliseconds (msec).
ACSII characters not included in the command set are ignored.
Refer to Table 3-2 for list of commands included in the command set.
(the delay is relay settling time—see ASCII Command “D”), an
ASCII “1” is sent over the RS-232 bus indicating the settling time
has expired. Response must be “on” to send the “1” (see ASCII
command R).
tion character is received from the RS-232 controller, the relay(s)
close(s) and a delay occurs (the delay is relay settling time—see
ASCII Command “D”). After the relay settling time expires, an
ASCII “1” is sent over the RS-232 indicating settling time has
expired. Response must be “on” to send the “1” (see ASCII command R).
This is the delay occurring after a command is issued that allows the
relays to change state. Commands that use this delay are the A, C,
and O commands. The default for this command is 15msec. Sending this command without a parameter queries the delay time.
I or iNoneReturns firmware information. This command retrieves firmware
information over the RS-232. After the command is sent, “Keithle y
Instruments Inc., Model 7999-5, rev A01” (or similar, due to firmware revision level) will be returned over the RS-232.
O or o<list>Opens specified relay. After the open command is sent and the ter-
mination character is received from the RS-232 controller, the
relay(s) open(s) and a delay occurs (the delay is relay settling
time—see ASCII Command “D”). After the relay settles, an ASCII
“1” is sent over the RS-232 indicating settling time has expired.
Response must be “on” to send the “1” (see ASCII command R).
<list>Comma separated relay list with values from 1–16
<delay> 1–250ms
<b><0, 1> where 0 = OFF and 1 = ON
Operation3-5
Table 3-2 (Continued)
Command set
ASCII Command Parameter TypeDescription
Q or q1–16Queries for a single relay setting. The parameter specifies the relay.
If the queried relay is open, an ASCII 0 will be returned. If the queried relay is closed, an ASCII 1 will be returned. If an invalid relay
number is sent, or inv alid parameter received (including no parameter), then an ASCII “?” is returned.
R or r<b>Response after delay (the delay is relay settling time—see ASCII
Command “D”). This response occurs when using the A, C, and O
commands. The default for this command is 1 (on). Sending this
command without parameters queries the response state (if a 1 is
returned, the response is on, if a 0 is returned, the response is off).
S or sNoneQueries all closed relays. Upon receiving this command, a comma
separated list in ASCII will be returned indicating the closed relays.
If no relays are closed, a comma will be returned.
<list>Comma separated relay list with values from 1–16
<delay> 1–250ms
<b><0, 1> where 0 = OFF and 1 = ON
Command interpretation
The Model 7999-5 requires each command to end with a termination character.
On a single line, the first valid ASCII character is interpreted as the command. The remaining characters are interpreted as the parameter data. This parameter data processing continues
up to the termination character. When the termination character is received, the command is
performed. Therefore, end each command with a termination character (line feed and/or carriage return) before sending a new command.
While processing the parameter data, if an ASCII character is invalid, it is ignored. Finding
an invalid character does not abort the parameter data from being processed.
Leading zeros contained in the parameter list for the C, O, and Q commands are ignored.
The parameter processing starts with the first non-zero digit and continues one additional digit.
Commas separate each individual parameter until a termination character. Leading zeros contained in the parameter data are also ignored for the D command. The parameter processing
starts with the first non-zero digit but continues two additional digits. Values interpreted as
greater than 250 are set to 250. The D command issued without parameters (or with a “0”,
which is ignored) issues a query.
Refer to Table 3-3 for command interpretation samples.
3-6Operation
NOTE
In the following samples (Table 3-3), <term> represents a valid termination character (line feed and/or carriage return).
The sample commands shown (the “ASCII characters sent,” e.g., C1,02 <term>,
etc.,) assume they are the first command sent or the first command sent after a valid
termination character.
Termination characters issued by the Model 7999-5 do not have to match the termination characters issued by the RS-232 control computer. Any valid termination
character can be received by the Model 7999-5 (line feed and/or carriage return).
Table 3-3
Sample command interpretation
ASCII characters sentResponse
C1,O2 <term>
Relays 1 and 2 are closed. The O(pen) is ignored because, even though it is a
valid command (after a termination character), it is an in v alid parameter for the
C(losed) command. 1 and 2 are interpreted for the parameter list.
O1, C2, Q4 <term>
Relay 1, 2, and 4 are opened. The C(losed) and Q(uery) are ignored because
they are invalid parameters to the O(pen) command, while 1, 2, and 4 are interpreted for the parameter list.
Q1;Q4 <term>
Relay 14 is queried. The 2nd Q(uery) command along with the “;” are ignored
because they are inv alid parameters to the Q(uery) command, while the 1 and 4
are interpreted as a 14 for the parameter.
O2, 3,
Relays 2 and 3 are opened when a termination character is received (a termination character in addition to the ASCII characters shown at the left has to be
sent for the command to be performed). Since no termination character has
been sent, parameters can still be added to the list.
C1O2 <term>
Relay 12 is closed. The O(pen) command is ignored because it is an invalid
parameter to the C(losed) command.
Q1,6 <term>
Relay 16 is queried. The comma is ignored because it is an in v alid character for
the Q(uery) command (the command does not accept a parameter list).
D008 <term>
D0325 <term>
Delay is set to 8msec. If queried, a response of 008 is returned.
Delay is set to 250msec (maximum value). If queried, a response of 250 is
returned.
T ypical connection scheme
WARNINGRelay contacts switching > 42 Vpk must be double insulated from relay
Figure 3-2 is a simplified schematic of a typical connection scheme. Although relay power
for each connector (upper and lower) can be provided from separate sources, both connectors
share a common chassis ground.
Figure 3-2
Typical connection scheme
Model 7999-5
coils.
Relay Power
(Upper Connector)
Relay power
(Lower Connector)
1
Relay Coils
Operation3-7
+
≤ 28VDC
Relay Control
Relay Common
(Upper Connector)
Relay Common
(Lower Connector)
2–15
16
3-8Operation
4
Service Information
4-2Service Information
Introduction
This section contains service information for the Model 7999-5. The information is orga-
nized as follows:
•Handling and cleaning precautions
•Performance verification
•Component replacement
WARNINGThe information in this section is intended only for qualified service per-
sonnel. Some of the procedures may expose you to hazardous voltages that
could result in personal injury or death. Do not perform these procedures
unless you are qualified to do so.
Handling and cleaning precautions
Care should be taken when handling or servicing the relay controller to prevent possible
contamination. The following precautions should be observed when servicing the relay
controller.
Handling precautions
Observe the following precautions when handling the relay controller:
•Handle the relay controller only by the edges and cover.
•Do not touch any board surfaces or components not associated with the repair.
•Do not store or operate the relay controller in an environment where dust could settle on
the circuit board.
Card and connector cleaning
•Use dry nitrogen gas to clean any dust off the circuit board and components.
•Clean the contaminated area with methanol, then blow dry the entire board with dry
nitrogen gas.
•Before use, allow items cleaned to dry for several hours in a 50˚C low-humidity environment. Use dry nitrogen to decrease drying time.
Replacing components
Replacement parts
Replacement parts can be obtained directly from Keithley Instruments, Inc. See the parts list
in Section 5 for part numbers.
Replacement precautions
CAUTIONObserve the following precautions when replacing components:
•To avoid contamination, which could degrade relay controller perfor-
mance, always handle the relay controller only by the covers and side
edges. Do not touch the connector, board surfaces, or components on
the relay controller.
•Use care when working with components from the PC board to avoid
pulling traces away from the circuit board.
Soldering considerations
Service Information4-3
When using solder on the circuit board, observe the following precautions:
•Use an OA-based (organic activated) flux, and take care not to spread the flux to other
•Remove the flux from the work areas when the repair has been completed. Use pure
•Once the flux has been removed, swab only the repaired area with methanol, then blow
•After cleaning, allow the card to dry in a 50˚C low-humidity environment for several
Disassembly
Perform the following steps to disassemble the Model 7999-5 to gain access to parts on the
circuit board:
1.Remove the six screws that hold the case together and any hex-nuts on the connectors.
2.Separate the two halves of the case.
3.Unplug the connectors from the board (J1004 and J1002).
4.Remove the screws that secure the PC board to the case, then remove the board.
areas of the circuit board.
water along with clean cotton swabs or a clean soft brush to remove the flux.
dry the board with dry nitrogen gas.
hours before use.
4-4Service Information
Performance verification
The following paragraphs discuss performance verification procedures for the Model 7999-5
and include an output saturation voltage verification procedure.
CAUTIONContamination will degrade the performance of the relay controller. To
avoid contamination, always grasp the relay controller by the cover; do not
touch the connectors.
NOTEFailure of any performance verification test may indicate that the multiplexer relay
controller is contaminated. See “Handling and cleaning precautions” earlier in this
section for information on cleaning the relay controller.
Environmental conditions
All verification measurements should be made at an ambient temperature between 18˚ and
28˚C, and at a relative humidity of less than 70%.
Recommended equipment
Table 4-1 summarizes the equipment necessary for performance verification (channel resis-
Perform the following steps to verify that the relay control lines output saturation voltage is
within specification.
WARNINGUse care around the resistor used in this test—the resistor will heat. Make
sure to take adequate precautions to avoid burns when disconnecting and
connecting the resistor.
1.Turn on the Model 2010 DMM, and allow it to warm up for one hour before making
measurements.
2.Connect a 100Ω, 10W resistor between the relay control line under test (start with line 1
and work through line 16) and the 28VDC power supply (see Figure 4-1).
3.Set the Model 2010 DMM for voltage (DCV) and connect the two test leads to the
INPUT HI and LO terminals.
4.Connect the Model 2010 DMM test leads as shown in Figure 4-1. Connection is made
to relay control line under test and relay common.
5.Turn on the relay control line under test’s output (see Section 3 for operation
information).
6.Measure voltage. Using the setup described in this procedure, the voltage measurement
will be made at the relay control line. Acceptable saturation voltage should be
≤ 0.18VDC.
7.Repeat the procedure for the other relay control lines (2–16).
Service Information4-5
Figure 4-1
Output saturation
voltage test connections
POWER
Model 7999-5 Relay
Controller. See Section 2
for detailed connections.
CH1REM
SCAN
STEPCH2 CH3 CH4 CH5 CH6 CH7 CH8 CH9 CH10
TALK
LSTN
SRQ
SHIFT
TIMER
MX+B
SHIFT
DCV
LOCAL
EX TRIG
HOLD TRIG FAST MED SLOWAUTO ERR
dBm
%
dB
ACI
ACV
DCI
HOLD
LIMITS ON/OFFDELAY
TRIG
STORE
RECALL
SAVE SETUP
CONFIG HALT
OPEN CLOSE
STEP SCAN
REL FILT
CONT
Ω2Ω
TYPE
RS232
GPIB
DIGITS RATE
Model 2010 DMM
Relay Common
MATH
REAR
4W
BUFFER
STAT
2010 MULTIMETER
PERIOD SENSOR
FREQ
TEMP
4
RATIO
DRYCKT O COMP
RELFILTER
CAL TEST
EXIT ENTER
Relay Power
16
SENSE
INPUT
Ω 4 WIRE
HI
350V
1000V
!
PEAK
PEAK
LO
500V
PEAK
INPUTS
F
R
RANGE
AUTO
FRONT/REAR
3A 250V
RANGE
AMPS
1
100Ω 10W
+
28VDC
(+)
(-)
4-6Service Information
5
Replaceable Parts
5-2Replaceable Parts
Introduction
This section contains replacement parts information and also a component layout for the
Model 7999-5.
Parts list
Parts lists for the Model 7999-5 are contained in Table 5-1 and Table 5-2.
Ordering information
To place an order, or to obtain information concerning replacement parts, contact your
Keithley representative or the f actory (see front of manual for addresses). When ordering parts,
be sure to include the following information:
•Model number (Model 7999-5)
•Serial number
•Part description
•Component designation (if applicable)
•Keithley part number
Factory service
If the relay controller is to be returned to Keithley Instruments for repair, perform the
following:
•Call the Repair Department at 1-888-KEITHLEY for a Return Material Authorization
(RMA) number.
•Complete the service form at the back of this manual, and include it with the
instrument.
•Carefully pack the instrument in the original packing carton.
•Write ATTENTION REPAIR DEPARTMENT and the RMA number on the shipping
label.
Component layout
Component layout drawing (7999-5-100) is provided following parts list tables.
Replaceable Parts5-3
Table 5-1
Parts list—electronic components
Circuit designationDescriptionKeithley part number
Safety symbols and terms1-3
Sending and receiving data3-2
Shipment contents1-4
Soldering considerations
symbols and terms1-3
4-3
T
Termination characters3-2
U
Unpacking and inspection1-3
W
Warranty1-2
Service Form
Model No. _______________ Serial No. __________________ Date _________________
Name and Telephone No. ____________________________________________________
Company_______________________________________________________________________
List all control settings, describe problem and check boxes that apply to problem. _________________________
❑ Intermittent❑ Analog output follows display❑ Particular range or function bad; specify
_______________________________
❑ IEEE failure❑ Obvious problem on power-up❑ Batteries and fuses are OK
❑ Front panel operational ❑ All ranges or functions are bad❑ Checked all cables
Display or output (check one)
❑ Drifts❑ Unable to zero❑ Unstable
❑ Overload❑ Will not read applied input
❑ Calibration only❑ Certificate of calibration required❑ Data required
(attach any additional sheets as necessary)
Show a block diagram of your measurement including all instruments connected (whether power is turned on or
not). Also, describe signal source.
Where is the measurement being performed? (factory, controlled laboratory, out-of-doors, etc.)_______________
What power line voltage is used?___________________ Ambient temperature?________________________ °F
Relative humidity? ___________________________________________Other? __________________________
Any additional information. (If special modifications have been made by the user, please describe.)