Texas Instruments 990A13 User manual

MODEL 990A13 CHASSIS _
GENERAL DESCRIPTION

MODEL 990A 13 CHASSIS MAINTENANCE MANUAL,
GENERAL DESCRIPTION

LIST OF EFFECTIVE PAGES
Insert latest changed pages and discard superseded pages.
Note: The changes in the text are indicated by a change number at the bot-
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with the following exceptions:
m= A change number at the bottom of the page but no change bar indicates
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Model 990A13 Chassis Maintenance Manual, General Description
(2308774-9701)
Original Issue ........... cee eee ec ee eee ee eee enna August 1982
Change 1... ccc cece cece cece ee nee eee e nee neens February 1985.
© 1982, 1985, Texas Instruments Incorporated. All Rights Reserved.
No part of this publication may be reproduced, stored in a retrieval system,
or transmitted, in any form or by any means, electronic, mechanical, photo-
copying, recording, or otherwise, without the prior written permission of
Texas Instruments.
The manual consists of the most recent full revision (indicated as 0) and the following changed pages
since the last revision. The total pages and change numbers in this publication are as follows:
Page Change No. Page Change No. Page Change No.
Cover ..... cece e ween eee 1 2-30 - 2-31 ........006. 1 A-1 - A-3 ........0000. 0
Inside Cover............ 1 2-32 et et ee eee 0 An] co ccc eee ee nes 1
Title Page .............. 1 2-33 — 2-38 woes 1 A-5 —- A-6 wo. cc eee ee eee 0
Effective Pages .......... 1 7) . 0 Index-1 - Index-4 ....... 0
HH/iV .. ec eee ee ee 1 3-1 — 3-8 ... ce ee eee 0 Customer Response ...... 1
Vivssccvcvevvecveececee 1 MeL icc c ccc cece ween ee 0 Business Reply .......... 1
Vi-vili ow ee ee 0 Bnd ccc cee ee ete ee 1 Questionnaire ........... 1
1-1 -— 1-4 wo... eee eee. 1 4-3 - 4-9... cee eee 0 Business Reply .......... 1
1-§ —- 1-8 ...... ee eee 0 YS 0 1 Inside Cover ............ 1
2-1 - 2-29 2... . ee eee 0 4-11 — 4-18 ............ 0 Cover ....... cee eee eee 1

Important Safety Instructions
Before using your 990A13, please read and comply with the following instructions:
1
2.
. Read all of these instructions.
Save these instructions for later use.
. Follow all warnings and instructions marked on the product.
. There are not user serviceable, installable, or replaceable parts inside the Model 990A13 chas-
sis. The Model 990A13 chassis enclosure contains hazardous live electrical parts involving risk of
an energy hazard-high current levels, and risk of fire. Repairs to the chassis should be done by
trained service personnel.
. The card cage area of the 990A13 chassis contains hazardous live electrical components involv-
ing risk of electrical shock and energy hazard-high current levels. This manual contains informa-
tion and procedures for use by system designers, maintenance personnel, and trained system
maintenance operators. These procedures assume these personnel are familiar with electrical
hazards, and have a knowledge of basic hand tools and cabling techniques. A detailed knowl-
edge of computer hardware or software is not required.
. On models with standby power:
a. Replace battery with same type as originally supplied. Use of another battery may present a
risk of fire or explosion.
b. Battery may explode if mistreated. Do not disassemble or dispose of in fire. Keep away from
children and dispose of used battery properly.
. Power requirements:
a. Check the label on the product and ensure that the available power source meets the
requirements of the unit.
b. To maintain the safety of the machine use only power cord sets approved by the national
test house for the power source requirements of the product.
c. This product is a safety IEC Class | machine.
d. This machine is not designed for connection to an IEC “I.T.” power system.
. This product is designed for data processing use.
.
When
connecting
or
disconnecting
cables
to
the
machine,
ensure
that
the
power
switch
is
in
the
OFF (O) position. Disconnect the power cord set last.

10. It is expected that reasonable care will be exercised in the final installation and operation of this
11.
machine. The manufacturer dose not assume any liability for the improper installation, applica-
tion, or use of this machine.
Installation/application requirements:
a. Ensure the power on/off (I/O) switch easily accessible in the final design.
b. Cables used to interconnect the chassis and its printed wiring boards should be equivalent or
better grade than those supplied by Texas Instruments.
c. Unjacketed (single insulated) cables must not be used for external interconnections.
d. All cables not supplied by Texas Instruments, should be verified to comply with existing
electrical and fire safety codes and standards.
e. Final system configuration should be verified to comply with applicable EM! emissions
standards.
f. Final system configuration should be verified to comply with applicable product safety
standards.

Preface
Model 990A13 Chassis Maintenance Manual, General Description provides an introduction to the
Model 990A13 Chassis, T! part number 2309019. Installation instructions and basic operating
instructions are included. This manual is specifically limited to chassis information and does not
describe the many Texas Instruments 990-family computers and computing systems that include
the 990A13 chassis.
This manual serves as an independent document and as an introduction to the 990A13 field and
depot maintenance manuals.
Information in this manual is divided into four sections and one appendix:
Section
1 Introduction — Features, specifications, configurations and physical description.
2 Installation — Site requirements, unpacking, installation, cabling, and initial power-up
procedures.
3 Operation — Use of the operator controls and indicator lights. Preventive maintenance
procedures.
4 Nonstandard and OEM Installation Data — Technical data for installations not part of a
standard Texas Instruments system, or those including customer-designed devices.
Appendix
A Standby Power Supply Installation — Installation procedure for the optional standby
power supply.
The following manuals also describe the Model 990A13 Chassis:
Title
Model 990A13 Chassis Maintenance Manual,
Field Theory and Maintenance (available as
part of manual kit 2308772-1)
Model 990A13 Chassis Maintenance Manual,
Depot Theory and Maintenance (available as
part of manual kit 23087 72-2)
990 CRU/TILINE Expansion Maintenance Manual,
General Description
2308774-9701 Change 1
Part Number
2308775-9701
23087 76-9701
2272075-9701
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2308774-9701
Contents
Title Page
1 — Introduction
at =Y= 10 | 6 ~~ 1-1
Chassis Configurations ....... cc ccc ee ee ee ee eee te eee eee teen ee ee eens 1-3
High and Low Voltage InputS .......... cee ee eee eee eee eens 1-3
Standby Power Supply ......... cece eee eee ee eee eee eee eee tenn eans 1-3
Computer and Expansion Chassis ....... 0... cece cece eee e ee ete teen nea 1-3
Chassis Specifications .. 0.0... cc ee eet ee eee eee eee e eee neee 1-4
Physical D@SCIrIPtION 2.0... ee tt tee eee eee ene e etn e eens 1-6
T=) =) | 2-1
Site REQUIFEMEMNES ....... cece te eee ee eee eee eee eee e eee teeta 2-1
Electrical Power Connectors and Cord SetS ......... cece cette tenes 2-1
Electrical Power Distribution and Grounding ........ 0... cece eee eee eee eens 2-2
Environmental RequireMentS ........ ccc ce ee ee eee eee eee eee teens 2-2
Space RequireMents ... 1... cece eet tee ee eee eee eee e eee tenes 2-5
UNPaCkiNg .. 1... ce eee ee et eee eee eee tee eee eee ee neee 2-6
Standby Power Supply Installation 2.0... 0.0... cece ee teen e te eee neees 2-9
Chassis Installation in an EIA Cabinet ......... 0... cc cece et eee eee e een eee 2-10
Installing the Air Filter and Front Trim Panels ............ cece ee cee ee eee 2-15
Chassis Slot Selection and Preparation .......... ccc eee ec eet ee eee eee nes 2-17
Installing a Center Card Guide ...... ccc cc cere teen teenies 2-17
Installing the Interrupt Board ................6. Se ee 2-20
TILINE Access-Granted JUMPErs ....... cc ee ee eee ee ee eee 2-22
Logic Board Installation and Cabling ............... ere 2-24
Shielded Logic Boards ...... ce ee ee eet eee eee eens 2-24
Installing Shielded Boards ........ cece eee eee eee eens 2-26
EMI Suppression with Shielded Boards ............ cc eect eee tee eee 2-28
Cabling Shielded Boards .......... cee eee eee eee eee ene 2-30
Conventional Logic Boards ... 0... ccc eee eee ee ee eee teen ees 2-31
Installing Conventional Boards ....... cc eee eee eee 2-32
Cabling Conventional Boards ........ 0... cece ee ee ee ene eens 2-33
Connecting the Control and Display Pane! (Computer Chassis) ............ 2-34
Connecting the Display Panel (Expansion Chassis) .......... cece eee eee eee 2-35
Line Power Connection .... 0... ee ee ee eee eee ee eee eens 2-36
Initial Power UD oo. e eEEeeEeeeeeS 2-36
Verification Of Operation .. 0... cee eee eee eens ee 2-36
Change 1 ix

Contents
Paragraph Title
3 — Operation
4 — Nonstandard and OEM Installation Data
4.1 INTTOGUCRION 2... cc ce tee eee et eee teen ete ee eee eeaes
4.2 Communications Register Unit ....... 0... cc cee ee ee eee tenes
4.2.1 CRU AdGresSiNg .... ccc ee cc eee eee eee et eee e anaes
4.2.2 CRU Expansion .. 0... ccc ce ce ee te eee e eee eee te eeees
4.3 | | a
4.3.1 TILINE Access-Granted Jumpers ........ 0. ccc cc ee ee eee teens
4.3.2 TILINE Expansion ........ ccc cc ec eee cette ee eee tet eect enes
4.4 Tah <=) aa 0) ©) (-
4.4.1 Standard Interrupt AssignmentS ....... 0... cc eee eee cere eres
4.4.2 Programmable Interrupt Kit ....... Lecce eee eee eee ee eens
4.4.2.1 Interrupt Planning ........ cc cece ee eee ee eee tenet eee eee
4.4.2.2 Interrupt WITINQG 2... cee eee teeter eee eee ene
4.5 Chassis Power Planning ....... ccc cece cece rete e eee erste eeees
Appendixes
Appendix Title
A Standby Power Supply Installation ........ 0. cece wee weer ewes
index
3.1 INtTFTOGUCTION 2... eee ec ee tee ee ee ee eee eee eee eee eee
3.2 Power-Up/Power-Down ProcedureS ........ cc cece eee eee ee eee
3.2.1 Power-Up Procedure ..... cece ce te eee ee eee eee as
3.2.2 Power-Down Procedure ...... ce ccc eee te eee tenes
3.3 Standby Power Control ......... 0c cee ee ecw ee ee eee eee eens
3.4 Control and Display Panel Operation ........... 0... cece eee ees
3.5 Operator Preventive Maintenance .......... ccc cece eee ee teens
3.5.1 Cleaning the ChassiS .......... cece ee eee ee tee eet eee e nee
3.5.2 Vacuuming the Air Filter... 1... ee ee ee ete eee
3.5.3 Replacing the Air Filter 2.0... cc eee ee ete eee ee eee
Page
246267-9701

Contents
_ Illustrations
Figure Title Page
1-1 Model 990A13 Chassis — Front View with 990/10A Central Processor ........ 1-2
1-2 Model 990A13 Chassis with Trim Panels Removed ...........0 ccc euecueees 1-6
1-3 Model 990A13 Chassis — Rear ViOW........ ee eee et eee eee eens 1-7
2-1 Power Cord Sets and Connectors ..... 0. ccc ce ete eee eee eee ees 2-3
2-2 BS 1363 Fused Power Connector for Great Britain ........ ee ee ees 2-4
2-3 Cooling Air FIOW . oc. ccc cc cc ete eee eee eee ete nett ene e en enenes 2-4
2-4 Chassis Minimum Access RequirementS ..........0c cc eee eee eee nents 2-6
2-5 Unpacking the 990A13 Chassis and Trim Panel Kit ......... 0002 ce cece eee 2-7
2-6 Perspective View of Slid@ MOuntS ......... cece eee ee ee eee eee ete 2-11
2-7 EIA Mounting RailS 0.0... cc ct tee ee eee eee eee eee eee eee eens 2-12
2-8 Bottom View of Chassis for Mounting ........... cc cece eee ec ete teens 2-14
2-9 Installing the Air Filter... . ce ee ee ee ee eee eee eee teen tees 2-16
2-10 Chassis Side View for Center Card Guide Installation ...............20 00s 2-18
2-11 Center Card Guide Installation in a Model 990A13 Chassis ................ 2-19
2-12 Interrupt Boards .... ccc ce te ee eee eee ee etter eee eee nent ees 2-20
2-13 Interrupt Board Installed in Demonstration Chassis .............00 0c ee eeee 2-21
2-14 TILINE Access-Granted Jumper Locations for 990A13 Chassis ............. 2-23
2-15 Shielded Logic Board ............ eee eee ee eee eee eee nee e tee eee 2-25
2-16 Installing/Removing an Insulator Sle@Ve ... 1... ee ee eee 2-27
2-17 EMI ClamMpS ..... ccc cc ce ee te eee eee ee eee eee eee te eee e eee nett ees 2-29
2-18 Conventional Logic Boards ........ cece ec ec ete ee tee ete e teen nena 2-31
2-19 Connecting the Control and Display Panel ......... cece ec ee tee ee 2-34
2-20 Connecting the Display Panel .......... ee ec ee ec et eet ene eees 2-35
3-1 Control and Display Panel .. 0... cc ec ec cee e ee eee eee ee eens 3-3
3-2 Replacing the Air Filter 2.0... ce ee cee eee tte eee teens 3-8
4-1 CRU Base Address Assignments by Slot Location ............ cee eee eee 4-3
4-2 Interrupt Assignments — Type 13-1 Interrupt Board ......... ccc eee ee eee 4-5
4-3 Interrupt Jumper — Type 13-1 Interrupt Board ........... cee eee ees 4-6
4-4 Programmable Interrupt Kit 2.0... . ce ee eee ee eee eee ee eee 4-7
4-5 Programmable Interrupt Board ........ cece cee eee eee beeen eee eees 4-8
4-6 Daisy-Chain Connection to One Interrupt Level ........... ce eee ee ee 4-9
4-7 Interrupt Planning and Wiring ChartS ...... 0... ccc cee ee ee eee ee eee eee 4-11
4-8 Sample Interrupt Planning and Wiring Charts ....... cece eee eee ee eens 4-12
4-9 Sample Interrupt Wiring Schematic ........ 0... cece eee ee ee eee 4-13
4-10 Template for Interrupt Wiring Schematic ........... cece eee ee eee eee 4-14
4-11 Inserting a Wire with the Adapter Tool ......... ccc cee ee eee rete eens 4-16
246267-9701
xi

Contents
Tables
Table Title Page
1-1 Model 990A13 Chassis Specifications .......... ccc cc cece eee ee ee eee teenies 1-4
1-2 FUSE Data 2... cc ec ccc ce ee ee tet e eet tet eee ete ee eee enes 1-8
3-1 Control and Display Panel Functions ....... 0... cece eee cee eee eee teenies 3-4
xii
246267-9701

Introduction
1.1 FEATURES
A Model 990A13 Chassis (Figure 1-1) provides mounting space, cooling air, shielding, operating
voltages and signal connections for a Texas Instruments 990-family computer. The 990A13 com-
bines a rugged, attractive enclosure with a massive power supply to provide the basis for a reliable
low-maintenance computing system.
CAUTION
The Model 990A13 Chassis contains static-sensitive electronic
components. To avoid damage to these components, ensure that
you are well grounded before you remove or handle the printed cir-
cuit boards. The recommended method is to use a static-control
floor or table mat and a static-control wrist strap. These are commer-
cially available. If you do not have a static-control system, you can
discharge any accumulated static charge by touching a grounded
object prior to handling the board. Then, as a further precaution,
place the printed circuit board on a grounded work surface after you
remove it from the assembly or from its protective package. Before
storing or transporting the printed circuit board, return it to its pro-
tective package or the assembly.
Chassis features include:
e Mounting slots for up to 13 full-sized 990 logic boards or a combination of full-sized and
half-sized boards
e Interrupt assignment by fixed or programmable circuit board
e TILINE* and communications register unit (CRU) bus
e Control and display panel that provides basic controls, status indicators, and a four-digit
(hexadecimal) address and data display
e Front panel intake and filtration of cooling air, with a plenum and four exhaust fans to
provide reserve cooling capacity
* TILINE is a trademark of Texas Instruments Incorporated.
230877 4-9701 Change 1 1-1

Introduction
Switching power supply that provides up to 65 amperes of +5-volt logic power plus
other voitages required by 990 logic boards
Optional standby power supply and battery pack that provide memory refresh voltages
to prevent data loss during short-duration power failures
Low-voltage and high-voltage versions that span the customary ac line voltages/
frequencies of most countries
Extensive shielding and filtering to prevent EMI (electromagnetic interference) emission
F
a
oi
eee
2282978
Figure 1-1. Model 990A13 Chassis — Front View with a 990/10A Central Processor ©
1-2 Change 1 2308774-9701

introduction
1.2 CHASSIS CONFIGURATIONS
The 990A13 chassis is available in several variations to meet the needs at your site. Major select-
able items include high or low voltage ac input power, a standby power supply option, and two ver-
sions for use as a computer chassis or aS an expansion chassis.
1.2.1 High and Low Voltage Inputs
Customary ac line voltages throughout the world range from 100 volts to 240 volts nominal, with a
plus or minus 10 percent tolerance. A low-voltage chassis covers the input voltage range from 90
to 132 volts, and a high-voltage chassis covers the range from 180 to 264 volts. The two versions
differ only in the fan/control assembly, which is the chassis rear panel. An ac line cord and fuse
adapt the chassis to the power distribution system in a specific country.
1.2.2 Standby Power Supply Option
Any programs and data in the computer memory are normally lost when you turn off ac power or if
a power line failure occurs. A battery-powered standby power supply is available for applications
in which a loss of memory contents is unacceptable. This option, available factory-installed or as
an add-on, supplies critical memory refresh power rather than full computer operating power.
A standby power supply is a solution for brownout and short-term power loss; with a fully-charged
battery, the computer will save memory contents for approximately 45 minutes. A standby power
supply works with either the low-voltage or the high-voltage version of the 990A13 chassis.
Wire standby power only to slots 1-7. Do not install memory with critical refresh requirements in
slots 8-13. Certain CPUs require jumpers to enable standby operation of on-board memory.
The standby power supply ON/OFF switch is concealed behind the chassis trim panels and the
ON and OFF labels are molded into the air filter framework.
1.2.3 Computer and Expansion Chassis
A computer chassis includes a control and display panel that provides controls, status displays,
and numeric data/address displays for a 990-family central processor. In addition to the central
processor board (or boards), a computer chassis may contain memory boards, disk controller
boards, and other circuit boards.
Some computing systems require more circuit boards than can fit in a single chassis, or require
more dc power than one chassis can provide. In this case, the circuit boards may be distributed
between a computer chassis and an expansion chassis. Either the TILINE or the CRU bus (or both)
must be extended to the expansion chassis.
An expansion chassis has a single power indicator instead of a control and display panel. Other-
wise, a computer chassis and an expansion chassis are identical.
2308774-9701
Change
1
1-3

Introduction
1.3. CHASSIS SPECIFICATIONS
Table 1-1 summarizes the specifications for the Model 990A13 Chassis.
Table 1-1.
Model 990A13 Chassis Specifications
1-4
Dimensions
Height at front trim panel
Width |
Depth
Overall
Behind panel
Weights
Chassis (no options)
Standby power option
Typical logic board
Mounting requirements
Power supply outputs
+5 main (+5.1 Vde + 3%)
Without standby
With standby
+ 12 main (+ 12.0 Vde + 3%)
Without standby
With standby
— 12 main (— 12.0 Vdc + 6%)
Without standby
With standby
—5 memory (- 5.0 Vdc + 6%)
Without standby
With standby
Line power
Battery power
+ 12 memory ( + 12.0 Vdc + 3%)
Without standby'
With standby
Line power
Battery power
+5 memory (+ 5.1 Vde +3%)
Without standby’
With standby
Line power
Battery power
Notes:
311 mm (12.25 in.)
483 mm (19.0 in.)
628.6 mm (24.75 in.)
594 mm (23.4 in.)
22.0 kg (48.5 !b)
4.1 kg (9.0 Ib)
0.7 kg (1.5 Ib)
483 mm (19 in) cabinet or EIA RS310B cabinet
5 A to 65 A max
5A to 59 Amax
4A
2A
2.5A
2A
0.1A
0.1A
0.1A
2A
1A
6A
3A
' Supplied by main power supply output at the same voltage.
Change 1
2308774-9701

Introduction
Table 1-1. Model 990A13 Chassis Specifications (Continued)
Heat load
Any single slot
Power supply
Acoustic noise (not in cabinet)
Electromagnetic interference (EMI)
Conduction/radiation
Power input requirements
Input voltage
Low voitage
High voltage
Input frequency
Input power
Environmental limits
Ambient temperature
Operating?
Storage
Humidity
Operating
Storage
Altitude (operating)
Storage
Vibration limits
Operating
Nonoperating
Shock limits
Operating
Nonoperating
Notes:
30 watts avg; 60 watts max
250 watts max
NC 47 or less
Meets limits specified by FCC Docket
20780 (Class A), VDE 0871 (Level A)
90 to 132 Vac, 3-wire service
(line, neutral, earth)
180 to 264 Vac, 3-wire service
(line, neutral, earth)
47 to 63 Hz
900 VA max
0° to 50° C (32° to 122° F)
— 40° to 60° C (— 40° to 140° F)
5% to 90% noncondensing
0% to 90% noncondensing
— 300 to 3048 meters (— 984 ft to 10000 ft)
— 300 to 12192 meters ( — 984 ft ta 40000 ft)
0.5 g, 10 to 250 Hz
0.5 g, 10 to 250 Hz
Any axis +29, 15 ms
X-axis +159, 30 ms
Y-axis +20 g, 30 ms
Z-axis +30 g, 30 ms
2 Derate maximum operating temperature 2° C for each 300 meters altitude above sea level.
2308774-9701
1-5

Introduction
1.4 PHYSICAL DESCRIPTION
Physical details of the Model 990A13 Chassis are shown in Figure 1-1, Figure 1-2, and Figure 1-3.
The main body of the chassis is a zinc-plated, sheet steel assembly that provides shielding and
serves as a strong mounting structure for other chassis parts.
Two grey plastic trim panels serve as cooling air intakes and restrict casual contact with control
switches and test features. Both of these removable panels are secured by snap catches at the
outer edges. Removing the panels is a normal operator procedure, and does not pose any hazards
to personnel or operations.
A disposable plastic air filter is located behind the trim panels. An interference fit between square
pegs on the filter and round holes in the sheet metal holds the filter in place. The filter fits flush
against a slotted metal grill that provides airflow, fingerproofing and shielding. A cutout in the
lower left corner of the filter provides access to the optional standby power supply switch. ON and
OFF labels molded into the filter identify the standby power supply switch settings.
Operating controls, status indicators, and numeric displays are located in the control and display
module. A cutout in the upper trim panel provides access to switches and displays. The test con-
nector and data security switch are hidden when the trim panel is in place. The data security
switch allows you to enable the panel controls, enable a remote test panel, or disable all manual
inputs. Section 3 (Operation) provides descriptions of all control and display panel switches.
2282979
Figure 1-2. Model 990A13 Chassis with Trim Panels Removed
1-6
2308774-9701

Introduction
An expansion chassis has a display module that provides a power-on indicator, with no controls
and no test connector.
The chassis provides 13 horizontal mounting slots for the plug-in circuit boards that make up a
computer system. Access to the slots is on the right side, viewed when facing the front of the
chassis.
Each slot has two connectors that mate with edge connectors on the plug-in circuit boards. A
shielded backpanel supports the connectors and provides operating power distribution and signal
connections between slot positions.
Slot 1 (the top slot) is reserved for a central processor board in a computer chassis, and for a CRU
buffer board in an expansion chassis. Slots 2 through 13 are general-purpose slots that can be
used for other 990-family boards. With the addition of an optional center card guide kit, Tl! part
number 940045-2, a chassis slot can hold 1 or 2 half-size 990 boards, up to a maximum of 24 ina
single chassis.
rn an
ied
oN
Pd
~
Cd
~
*
nn
ai
2282980
Figure 1-3. Model 990A13 Chassis — Rear View
2308774-9701 1-7

Introduction
Interrupt connections between slot 1 and slots 2 through 13 are made by an interrupt board in-
stalled directly above slot 1. Interrupt boards are available in standard and programmable
versions.
A movable sill and a pair of adjustable leaf clamps above slot 1 form the upper part of an elec-
tromagnetic interference (EMI) shield for the logic boards. An adjustable sill below slot 13 and
shield/stiffeners on the logic boards complete the shield, as described in Section 2.
Figure 1-3, the chassis rear view, shows the fan/control assembly which includes four exhaust
fans, an ac power input connector, line fuse and the ac power ON-1/OFF-0 switch. This panel
determines whether the chassis is a low-voltage or high-voltage version.
Power enters the chassis on a CEE (22) VI connector that includes a built-in filter. The fuse is
either a UL/CSA-approved type GLH fuse or a 5 by 20 millimeter type SPT fuse, depending on
whether a US or international fusecap is installed. Either type requires a screwdriver for access to
the fuse. A label identifies the fuse type and current rating. Table 1-2 summarizes the fuse data
and supplies Texas Instruments and manufacturer part numbers.
Table 1-2. Fuse Data
Fuse Voltage Current
Type Range Rating Source Part Number
GLH Low 10.0 A TI 0416434-5
Bussman Mfg GLH10
SPT High 5.0 A Tl 2220531-8
H. Schurter AG 034.3124
1-8 2308774-9701