ISO/IEC 17462:2000
(Main)Information technology — 3,81 mm wide magnetic tape cartridge for information interchange — Helical scan recording — DDS-4 format
Information technology — 3,81 mm wide magnetic tape cartridge for information interchange — Helical scan recording — DDS-4 format
This International Standard specifies the physical and magnetic characteristics of a 3,81 mm wide magnetic tape cartridge to enable physical interchangeability of such cartridges between drives. It also specifies the quality of the recorded signals, the recording method and the recorded format - called Digital Data Storage 4 (DDS-4) - thereby allowing data interchange between drives by means of such magnetic tape cartridges. Information interchange between systems also requires, at a minimum, agreement between the interchange parties upon the interchange code(s) and the specifications of the structure and labelling of the information on the interchanged cartridge. Under information interchange circumstances in which a processing algorithm, e.g. for lossless data compression as specified in ISO/IEC 11558, is applied to the host data prior to recording on the tape and a complementary reprocessing algorithm is applied after the data is read from the tape, agreement upon these by the interchange parties is also required.
Technologies de l'information — Cartouche à bande magnétique de 3,81 mm de large pour l'échange d'information — Enregistrement par balayage en spirale — Format DDS-4
General Information
Standards Content (Sample)
INTERNATIONAL ISO/IEC
STANDARD 17462
First edition
2000-09-15
Information technology — 3,81 mm wide
magnetic tape cartridge for information
interchange — Helical scan recording —
DDS-4 format
Technologies de l'information — Cartouche à bande magnétique de
3,81 mm de large pour l'échange d'information — Enregistrement par
balayage en spirale — Format DDS-4
Reference number
ISO/IEC 17462:2000(E)
©
ISO/IEC 2000
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ISO/IEC 17462:2000(E)
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ISO/IEC 17462:2000 (E)
Contents
Section 1 - General 1
1 Scope 1
2 Conformance 1
2.1 Magnetic tape cartridge 1
2.2 Generating drive 1
2.3 Receiving drive 1
3 Normative references 2
4 Definitions 2
4.1 Absolute Frame Number (AFN) 2
4.2 a.c. erase 2
4.3 Access Point 2
4.4 algorithm 2
4.5 Area ID 2
4.6 Average Signal Amplitude 2
4.7 azimuth 2
4.8 back surface 2
4.9 byte 2
4.10 cartridge 2
4.11 Channel bit 2
4.12 Codeword 2
4.13 Data Format ID 2
4.14 Early Warning Point (EWP) 2
4.15 End of Data (EOD) 2
4.16 Entity 2
4.17 Error Correcting Code (ECC) 2
4.18 flux transition position 2
4.19 flux transition spacing 2
4.20 Fragment 2
4.21 Frame 3
4.22 Housekeeping Frame 3
4.23 Logical Beginning of Tape (LBOT) 3
4.24 magnetic tape 3
4.25 Master Standard Amplitude Calibration Tape 3
4.26 Master Standard Reference Tape 3
4.27 Optimum Recording Field 3
4.28 Partition Boundary 3
4.29 Physical Beginning of Tape (PBOT) 3
4.30 Physical End of Tape (PEOT) 3
4.31 physical recording density 3
4.32 pre-recording condition 3
4.33 processing 3
4.34 processed data 3
4.35 Processed Record 3
4.36 Processed Record Sequence 3
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ISO/IEC 17462:2000 (E)
4.37 record 3
4.38 Reference Recording Field3
4.39 reprocessing 3
4.40 Secondary Standard Amplitude Calibration Tape 3
4.41 Secondary Standard Reference Tape 3
4.42 Separator Mark 4
4.43 Standard Reference Amplitude 4
4.44 Tape Reference Edge 4
4.45 Test Recording Current 4
4.46 track 4
4.47 Unprocessed Record 4
4.48 Virtual End of Tape (VEOT) 4
5 Conventions and Notations 4
6 Acronyms 4
7 Environment and safety 4
7.1 Testing environment 4
7.2 Operating environment 5
7.3 Storage environment 5
7.4 Transportation 5
7.5 Safety 5
7.6 Flammability 5
Section 2 - Requirements for the case 6
8 Dimensional and mechanical characteristics of the case 6
8.1 General 6
8.2 Overall dimensions 6
8.3 Loading grip 7
8.4 Holding areas 7
8.5 Notches of the lid 7
8.6 Lid dimensions 7
8.7 Optical detection of the beginning and end of tape 8
8.8 Bottom side 8
8.8.1 Locking mechanism of the slider 8
8.8.2 Access holes 9
8.8.3 Recognition, sub-datums, and write-inhibit holes 9
8.8.4 Datum holes 11
8.8.5 Access room for tape guides 11
8.8.6 Holes for accessing the hubs 11
8.8.7 Internal structure of the lower half 11
8.8.8 Light path 12
8.8.9 Support Areas 13
8.8.10 Datum Areas 13
8.8.11 Relationship between Support and Datum Areas and Reference Plane Z 13
8.9 Hubs 13
8.10 Attachment of leader and trailer tapes 14
8.11 Interface between the hubs and the drive spindles 14
8.12 Opening of the lid 14
8.13 Release of the hub locking mechanism 14
8.14 Label areas 14
8.15 Requirement for autoloaders 15
Section 3 - Requirements for the unrecorded tape 28
9 Mechanical, physical and dimensional characteristics of the tape 28
9.1 Materials 28
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ISO/IEC 17462:2000 (E)
9.2 Tape length 28
9.2.1 Length of magnetic tape 28
9.2.2 Length of leader and trailer tapes 28
9.2.3 Length of splicing tapes 28
9.3 Tape width 28
9.3.1 Width of magnetic tape 28
9.3.2 Width of leader and trailer tapes 28
9.3.3 Width and position of splicing tape 28
9.3.4 Edge weave 28
9.4 Discontinuities 29
9.5 Tape thickness 30
9.5.1 Thickness of magnetic tape 30
9.5.2 Thickness of leader and trailer tape 30
9.5.3 Thickness of splicing tape 30
9.6 Longitudinal curvature 30
9.7 Cupping 30
9.8 Coating adhesion 30
9.9 Layer-to-layer adhesion 31
9.10 Tensile strength 31
9.10.1 Breaking strength 31
9.10.2 Yield strength 31
9.11 Residual elongation 31
9.12 Flexural rigidity 31
9.13 Electrical resistance of coated surfaces 32
9.14 Abrasivity 32
9.15 Light transmittance of the tape 32
9.16 Media Recognition System (MRS) 33
10 Magnetic recording characteristics 33
10.1 Optimum Recording Field 34
10.2 Signal Amplitude 34
10.3 Resolution 34
10.4 Overwrite 34
10.5 Ease of erasure 35
10.6 Tape quality 35
10.6.1 Missing pulses 35
10.6.2 Missing pulse zone 35
10.7 Signal-to-Noise Ratio (SNR) characteristic 35
Section 4 - Requirements for an interchanged tape 35
11 Format 35
11.1 General 35
11.2 Basic Groups 36
11.2.1 Entity 36
11.2.2 Group Information Table 37
11.2.3 Block Access Table (BAT) 39
11.3 Sub-Groups 42
11.3.1 G1 Sub-Group 42
11.3.2 G2 Sub-Group - Randomizing 42
11.3.3 G3 Sub-Group 43
11.3.4 G4 Sub-Group 44
11.3.5 Main Data Fragment 48
11.3.6 Summary of the transformation of a Basic Group 50
11.4 Sub code information 50
11.4.1 Pack Item Number 0 50
11.4.2 Pack Item Number 1 50
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11.4.3 Pack Item Number 2 51
11.4.4 Pack Item Number 3 51
11.4.5 Pack Item Number 4 51
11.4.6 Pack Item Number 5 52
11.4.7 Pack Item Number 6 53
11.4.8 Pack Item Number 7 53
11.4.9 Pack Item Number 8 54
11.4.10 Pack Item Number 9 54
11.4.11 Pack Item Number 10 54
11.4.12 Pack Item Number 11 55
11.4.13 Pack Item Number 12 55
11.4.14 Pack Item Number 13 56
11.4.15 Pack Item Number 14 56
11.4.16 Pack Item Number 15 57
11.5 Sub code location 57
11.5.1 Sub code Pack Items on a Single Data Space tape 57
11.5.2 Sub code Pack Items on a partitioned tape 57
12 Method of recording 58
12.1 Physical recording density 58
12.2 Long-term average bit cell length 58
12.3 Short-term average bit cell length 58
12.4 Rate of change 58
12.5 Bit shift 58
12.6 Read signal amplitude 58
12.7 Maximum recorded levels 58
13 Track geometry 58
13.1 Track configuration 58
13.2 Average track pitch 59
13.3 Variations of the track pitch 59
13.4 Track width 59
13.5 Track angle 59
13.6 Track edge linearity 59
13.7 Track length 60
13.8 Ideal tape centreline 60
13.9 Azimuth angles 60
14 Recorded patterns 60
14.1 Recorded Main Data Fragment 60
14.2 Preamble Zone, Margin Zones 60
15 Format of a track 60
15.1 Format of a track 60
15.2 Positioning accuracy 60
15.3 Tracking scheme 61
16 LayoutofaSingleDataSpace tape 61
16.1 Device Area 61
16.2 Reference Area 62
16.3 Position Tolerance Band No. 1 62
16.4 System Area 62
16.4.1 System Preamble 62
16.4.2 System Log 62
16.4.3 System Postamble 62
16.4.4 Position Tolerance Band No. 2 62
16.4.5 Vendor Group Preamble 62
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ISO/IEC 17462:2000 (E)
16.5 Data Area 62
16.5.1 Vendor Group 62
16.5.2 Recorded Data Group 63
16.5.3 ECC3 63
16.5.4 Repeated Frames 63
16.5.5 Appending and overwriting 64
16.6 EOD Area 65
16.7 Post-EOD Area 65
16.8 Early Warning Point - (EWP) 66
16.9 Initialization 66
17 Layout of a partitioned tape 66
17.1 Overall magnetic tape layout 67
17.1.1 Device Area 67
17.1.2 Partition 1 67
17.1.3 Partition 0 68
17.2 Area ID 68
17.3 System Area Pack Items No. 6 68
17.4 Empty partitions 69
17.4.1 Empty partition 1 69
17.4.2 Empty partition 0 69
17.5 Initialization of partitioned tapes 69
18 Housekeeping Frames 69
18.1 Amble Frames 69
18.2 System Log Frames 69
18.3 Tape Management Frames 70
Annexes
A- Measurement of the light transmittance of the prisms 71
B- Measurement of light transmittance of tape and leaders 73
C- Measurement of Signal-to-Noise Ratio 76
D- Method for determining the Nominal and the Maximum Allowable Recorded Levels 77
E- Representation of 8-bit bytes by 10-bit patterns 78
F- Measurement of bit shift 90
G- Measurement of track edge linearity 92
H- Tape abrasicity measurement procedure 93
J- Method of measurement of the track width 95
K- Recognition Holes 97
L- Means to open the lid 98
M- Recommendations for transportation 100
N- Read-After-Write 101
P- Example of the content of a Basic Group No. 0 102
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ISO/IEC 17462:2000 (E)
Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical Commission) form the
specialized system for worldwide standardization. National bodies that are members of ISO or IEC participate in the
development of International Standards through technical committees established by the respective organization to deal with
particular fields of technical activity. ISO and IEC technical committees collaborate in fields of mutual interest. Other
international organizations, governmental and non-governmental, in liaison with ISO and IEC, also take part in the work.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 3.
In the field of information technology, ISO and IEC have established a joint technical committee, ISO/IEC JTC 1. Draft
International Standards adopted by the joint technical committee are circulated to national bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the national bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this International Standard may be the subject of patent rights.
ISO and IEC shall not be held responsible for identifying any or all such patent rights.
This International Standard was prepared by collaboration between the JISC and the ECMA Standard Bodies (as Standard JIS
X 6137 and ECMA-288) and was adopted, under a special “fast-track procedure” by Joint Technical Committee ISO/IEC
JTC 1, Information Technology, in parallel with its approval by national bodies of ISO and IEC.
Annexes A, B, C, D, E, F, G, H and J form a normative part of this International Standard. Annexes K, L, M, N and P are for
information only.
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INTERNATIONAL STANDARD ISO/IEC 17462:2000 (E)
Information technology – 3,81 mm wide magnetic tape cartridge for information
interchange - Helical scan recording - DDS-4 format
Section 1 - General
1Scope
This International Standard specifies the physical and magnetic characteristics of a 3,81 mm wide magnetic tape cartridge to
enable physical interchangeability of such cartridges between drives. It also specifies the quality of the recorded signals, the
recording method and the recorded format - called Digital Data Storage 4 (DDS-4) - thereby allowing data interchange between
drives by means of such magnetic tape cartridges.
Information interchange between systems also requires, at a minimum, agreement between the interchange parties upon the
interchange code(s) and the specifications of the structure and labelling of the information on the interchanged cartridge.
Under information interchange circumstances in which a processing algorithm, e.g. for lossless data compression as specified in
ISO/IEC 11558, is applied to the host data prior to recording on the tape and a complementary reprocessing algorithm is
applied after the data is read from the tape, agreement upon these by the interchange parties is also required.
2 Conformance
2.1 Magnetic tape cartridge
A tape cartridge shall be in conformance with this International Standard if it meets all the mandatory requirements specified
herein. The tape requirements shall be satisfied throughout the extent of the tape.
For each recorded Entity any algorithm for lossless data compression used for processing the data therein shall have been
registered, and according to ISO/IEC 11576 the corresponding numerical identifier shall be recorded in Byte No. 3 of the
Entity Header.
2.2 Generating drive
A drive generating a magnetic tape cartridge for interchange shall be in conformance with this International Standard if all
recordings on the tape meet the mandatory requirements of this International Standard, and if either or both methods of
appending and overwriting are implemented.
A claim of conformance shall state which of the following optional features are implemented and which are not
� the performing of a Read-After-Write check and the recording of any necessary repeated frames;
� the generation of ECC3 Frames.
In addition a claim of conformance shall state
� whether or not one, or more, registered algorithm(s) are implemented within the system and are able to process data
received from the host prior to collecting the data into Basic Groups, and
� the algorithm registration identification number(s) of the implemented algorithm(s).
2.3 Receiving drive
A drive receiving a magnetic tape cartridge for interchange shall be in conformance with this International Standard if it is able
to handle any recording made on the tape according to this International Standard. In particular it shall
� be able to recognize repeated frames and to make available to the host, data and Separator Marks from only one of these
frames;
� be able to recognize an ECC3 frame, and ignore it if the system is not capable of using ECC3 check bytes in a process of
error correction;
� be able to recognize processed data within an Entity, identify the algorithm used, and make the algorithm registration
number available to the host;
� be able to make processed data available to the host.
In addition a claim of conformance shall state
� whether or not the system is capable of using ECC3 check bytes in a process of error correction;
� whether or not one or more reprocessing algorithm(s) are implemented within the system, and are able to be applied to
processed data prior to making such data available to the host;
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ISO/IEC 17462:2000 (E)
� the algorithm registration number(s) of the processing algorithm(s) for which a complementary reprocessing algorithm is
implemented.
3 Normative references
The following normative documents contain provisions which, through reference in this text, constitute provisions of this
International Standard. For dated references, subsequent amendments to, or revisions of, any of these publications do not apply.
However, parties to agreements based on this International Standard are encouraged to investigate the possibility of applying
the most recent editions of the normative documents indicated below. For undated references, the latest edition of the normative
document referred to applies. Members of ISO and IEC maintain registers of currently valid International Standards.
ISO 527-1:1993 Plastics - Determination of tensile properties - Part 1: General principles.
ISO 1302:1992 Technical drawings - Method of indicating surface texture.
ISO/IEC 11576:1994 Information technology - Procedure for the registration of algorithms for the lossless compression
of data.
IEC 60950:1996 Safety of information technology equipment.
4 Definitions
For the purposes of this International Standard the following definitions apply.
4.1 Absolute Frame Number (AFN): A sequence number, encoded in the Frame.
4.2 a.c. erase: A process of erasure utilising magnetic fields of decaying intensity.
4.3 Access Point: A point, at the start of a Processed Record Sequence, at which the presentation of Codewords to a
reprocessing algorithm is required to start, regardless of whether the data of interest in a retrieval operation starts at
that point or at a subsequent point.
4.4 algorithm: A set of rules for transforming the logical representation of data.
4.5 Area ID: An identifier defining the area of the tape and specifying the types of Frame written.
4.6 Average Signal Amplitude: The average peak-to-peak value of the output signal from the read head at the
fundamental frequency of the specified physical recording density over a minimum of 7,8 mm of track, exclusive of
missing pulses.
4.7 azimuth: The angle, in degrees, minutes and seconds of arc, made by the mean flux transition line with a line normal
to the centreline of the recorded track.
4.8 back surface: The surface of the tape opposite to the magnetic coating which is used to record data.
4.9 byte: An ordered set of bits acted upon as a unit.
4.10 cartridge: A case containing a magnetic tape wound on twin hubs.
4.11 Channel bit: A bit after 8-10 transformation.
4.12 Codeword: A word which is generated by a processing algorithm.
4.13 Data Format ID: An identifier specifying which data format is being used on the tape.
4.14 Early Warning Point (EWP): A point along the length of the tape at which warning is given of the approach, in
the forward direction of tape motion, of the Partition Boundary or of the Physical End of Tape.
4.15 End of Data (EOD): The point on the tape at the end of the group which contains the last user data.
4.16 Entity: A unit of recorded data, comprising an Entity header and a Processed Record Sequence.
4.17 Error Correcting Code (ECC): A mathematical computation yielding check bytes used for the detection and cor-
rection of errors.
4.18 flux transition position: That point which exhibits maximum free-space flux density normal to the tape surface.
4.19 flux transition spacing: The distance along a track between successive flux transitions.
4.20 Fragment: A collection of bytes acted upon as a unit for recording, read back and error correction purposes.
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ISO/IEC 17462:2000 (E)
4.21 Frame: A pair of adjacent tracks with azimuths of opposite polarity, in which the track with the positive azimuth is
recorded first.
4.22 Housekeeping Frame: A Frame which contains no user data and which is identified as such by the values in the
data fields therein.
4.23 Logical Beginning of Tape (LBOT): The point along the length of the tape where a recording of data for
interchange commences.
4.24 magnetic tape: A tape which will accept and retain the magnetic signals intended for input, output and storage
purposes on computers and associated equipment.
4.25 Master Standard Amplitude Calibration Tape: A pre-recorded tape on which the standard signal amplitudes
have been recorded in the tracks of positive azimuth, 21,0µm wide, recorded at a track pitch of 27,2µm, on an a.c.
erased tape.
Note 1 - The tape is recorded with the nominal physical recording densities of 4 499,8 ftpmm, 2 999,9 ftpmm, 1 999,9 ftpmm and 1 499,9 ftpmm.
Note 2 - The Master Standard Amplitude Calibration Tape has been established by Sony Corporation.
4.26 Master Standard Reference Tape: A tape selected as the standard for Reference Recording Field, Signal Ampli-
tude, Resolution, Overwrite and Signal-to-Noise Ratio.
Note - The Master Standard Reference Tape has been established by Sony Corporation
4.27 Optimum Recording Field: In the plot of Average Signal Amplitude against the recording field at the physical
recording density of 2 999,9 ftpmm, the field that causes the maximum Average Signal Amplitude.
4.28 Partition Boundary: The point along the length of a magnetic tape at which partition 1 ends and partition 0
commences.
4.29 Physical Beginning of Tape (PBOT): The point where the leader tape is joined to the magnetic tape.
4.30 Physical End of Tape (PEOT): The point where the trailer tape is joined to the magnetic tape.
4.31 physical recording density: The number of recorded flux transitions per unit length of track, expressed in flux
transitions per millimetre (ftpmm).
4.32 pre-recording condition: The recording levels above which a tape intended for interchange shall not previously
have been recorded.
4.33 processing: The use of an algorithm to transform host data into Codewords.
4.34 processed data: A sequence of Codewords which results from the application of processing to data.
4.35 Processed Record: A sequence of Codewords which results from the application of processing to an Unprocessed
Record.
4.36 Processed Record Sequence: A sequence of one or more Processed Records which starts on an 8-bit boundary and
ends on a subsequent 8-bit boundary.
4.37 record: Related data treated as a unit of information.
4.38 Reference Recording Field: The Optimum Recording Field of the Master Standard Reference Tape.
4.39 reprocessing: The use of an algorithm to transform Codewords into data as required by the host.
4.40 Secondary Standard Amplitude Calibration Tape: A tape pre-recorded as defined for the Master Standard
Amplitude Calibration Tape; the outputs are known and stated in relation to those of the Master Standard Amplitude
Calibration Tape.
Note - Secondary Standard Amplitude Calibration Tapes can be ordered from Sony Corporation, 6-7-35, Kitashinagawa, Shinagawa-ku, Tokyo, 141-0001,
Japan, under Part Number TY 10000 G. It is intended that these tapes be used for calibrating tertiary reference tapes for use in routine calibration.
In principle, these Secondary Standard Amplitude Calibration Tapes will be available for a period of ten years from the first publication of this International
Standard. However, this period may be changed to take into account the demand for such Secondary Standard Amplitude Calibration Tapes.
4.41 Secondary Standard Reference Tape: A tape the performance of which is known and stated in relation to that of
the Master Standard Reference Tape.
Note - Secondary Standard Reference Tapes can be ordered from Sony Corporation, 6-7-35, Kitashinagawa, Shinagawa-ku, Tokyo, 141-0001, Japan, under
Part Number RSD 1098. It is intended that these tapes be used for calibrating tertiary reference tapes for use in routine calibration.
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ISO/IEC 17462:2000 (E)
In principle, these Secondary Standard Reference Tapes will be available for a period of ten years from the first publication of this International Standard.
However, by agreement between ISO/IEC and Sony Corporation, this period may be changed to take into account the demand for such Secondary Standard
Reference Tapes.
4.42 Separator Mark: A record containing no user data, which is used to separate data.
4.43 Standard Reference Amplitude: The Average Signal Amplitude from the tracks of positive azimuth of the Master
Standard Amplitude Calibration Tape at a specified physical recording density.
4.44 Tape Reference Edge: The bottom edge of the tape when viewing the recording side of the tape, with the PEOT to
the observer's right.
4.45 Test Recording Current: The current that produces the Reference Recording Field.
4.46 track: A diagonally positioned area on the tape along which a series of magnetic signals may be recorded.
4.47 Unprocessed Record: A record of unprocessed data, comprising an integral number of bytes.
4.48 Virtual End of Tape (VEOT): The point along the length of the magnetic tape within partition 1 which defines the
end of the part of partition 1 which is usable for recording data for interchange.
5 Conventions and Notations
A measured value is rounded off to the least significant digit of the corresponding specified value. This implies that, for
example, a specified value of 1,26 with a positive tolerance of +0,01 and a negative tolerance of -0,02 allows a range of
measured values from 1,235 to 1,275.
The setting of a bit is denoted by ZERO or ONE.
Bit patterns and numbers in binary notation are represented by strings of digits 0 and 1. Within such strings, X may be used to
indicate that the setting of a bit is not specified within the string.
Bit patterns and numbers in binary notation are shown with the most significant bit to the left and the least significant bit to the
right.
The most significant bit of an 8-bit byte is denoted by b8 and the least significant by b1.
The names of basic elements, e.g. specific fields, are given with a capital initial letter.
6 Acronyms
AEWP After Early Warning Point
AFN Absolute Frame Number
BAT Block Access Table
DF-ID Data Format Identifier
ECC Error Correcting Code
EOD End of Data
EWP Early Warning Point
GIT Group Information Table
LBOT Logical Beginning of Tape
LSB Least Significant Byte
LF-ID Logical Frame Identifier
MRS Media Recognition System
MSB MostSignificantByte
MSRT Master Standard Reference Tape
PBOT Physical Beginning of Tape
PEOT Physical End of Tape
RAW Read-After-Write
SNR Signal-to-Noise Ratio
VEOT Virtual End of Tape
7 Environment and safety
7.1 Testing environment
Tests and measurements made on the tape cartridge to check the requirements of this International Standard shall be carried out
in the following ambient conditions of the air immediately surrounding the drive :
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ISO/IEC 17462:2000 (E)
temperature : 23 °C±2 °C
relative humidity : 40 % to 60 %
conditioning period before testing : 24 h min.
7.2 Operating environment
Cartridges used for data interchange shall be capable of operating under the following conditions, as measured within 10 mm of
the tape exit from the drum of the generating or receiving drive :
temperature : 15 °Cto 55 °C
relative humidity : 10 % to 80 %
wet bulb temperature : 26 °Cmax.
There shall be no deposit of moisture on or in the cartridge.
The above conditions include any temperature rise that may occur while operating the drive.
Conditioning before operating:
If a cartridge has been exposed during storage and/or transportation to a condition outside the above values, before use the
cartridge shall be conditioned in the operating environment for a time at least equal to the period during which it has been out
of the operating environment, up to a maximum of 24 h.
Note - Rapid variations of temperature should be avoided.
7.3 Storage environment
For long-term or archival storage of cartridges the following conditions shall be observed:
temperature : 5 °Cto 32 °C
relative humidity : 20 % to 60 %
wet bulb temperature : 26 °Cmax.
The stray magnetic field at any point on the tape shall not exceed 4 000 A/m. There shall be no deposit of moisture on or in the
cartridge.
7.4 Transportation
Recommended limits for the environment to which a cartridge may be subjected during transportation, and the precautions to be
taken to minimize the possibility of damage, are provided in annex M.
7.5 Safety
The cartridge and its components shall satisfy the requirements of IEC 60950.
7.6 Flammability
The cartridge and its components shall be made from materials, which if ignited from a match flame, do not continue to burn in
a still carbon dioxide atmosphere.
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ISO/IEC 17462:2000 (E)
Section 2 - Requirements for the case
8 Dimensional and mechanical characteristics of the case
8.1 General
The case of the cartridge shall comprise
� an upper half,
� alower half,
� a slider movably mounted on the lower half,
� a lid pivotally mounted on the upper half.
In the drawings, using third angle projection, an embodiment of the cartridge is shown as an example.
Figure 1 is a perspective view of the cartridge seen from top.
Figure 2 is a perspective view of the cartridge seen from bottom.
Figure 3 is a partial view of the rear side.
Figure 4 is a schematic view showing the Reference Planes X, Y and Z.
Figure 5 shows the front side.
Figure 6 shows the top side with the lid in closed position.
Figure 7 shows the left side.
Figure 8 shows the top side with the lid in open position.
Figure 9 shows the left side with the lid in open position.
Figure 10 shows the bottom side with the lid and the slider in closed position.
Figure 11 shows the bottom side with the lid and the slider in open position.
Figure 12 is a view from the top of the inside of the lower half with the upper half removed.
Figure 13 is a view of the bottom half with the lid and the slider in open position.
Figure 14 is a view of the left side with the lid and the slider in open position.
Figure 15 is a top view of a hub.
Figure 16 is a side view of a hub with partial cross-section.
Figure 17 is a partial cross-section through a hub and both halves of the case showing the interface with the drive
spindle.
Figure 18 shows at a larger scale the lid in the open position.
Figures 19, 20 show at a larger scale the functional relationship between the lid and the locking mechanism of the hubs.
Figures 21, 22 sh
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