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2. SPECIFICATION
2. 3. 4 Load Time
Load Time means the period from the time when the operator inserts a cassette into the drive to the time when the drive
is ready.
Load Time is less than 24 seconds (for a single partition tape).
2. 3. 5 Rewind Time
Rewind Time means the period from the beginning to the end of rewinding sequence. This value depends on the tape
length and the position of the head along the tape.
Rewind Time is less than 80 seconds, when a 150 meter tape is loaded.
2. 3. 6 Search Time
Search Time means the period for the drive to find the position that is required by a command. This time also depends
on the tape length and the position of the head along the tape.
Search Time is less than 90 seconds, when a 150 meter tape is loaded.
2. 3. 7 Unload Time
Unload Time means the period from the beginning of the unload sequence caused by Unload Command or Eject button
to the time when a cassette is ejected from the slot.
Unload Time does not include Rewind time.
Unload Time is less than 20 seconds (for a single partition tape).
2. 3. 8 Error Rate
The uncorrectable bit error rate is expected to be less than 10
Format for Digital Audio Tape (DAT)", produced by the DDS Manufacturers Group.
2. 3. 9 Retry Limits on Rewrites
For Read-After-Write error correction, each frame can be rewritten up to a maximum of 255 times giving 256 writes of
the frame. With N-Group writing, where every group is written a fixed number of times, the upper limit is 8.
N-Group writing is not supported by DDS-3 and DDS-4.
2. 3. 10 Definition of Failure
A failure is defined as any permanent malfunction of the drive that prevents the user from retrieving data from tape. This
includes failure to power up, failure to unload or eject a cassette, or failure to write and read data to and from the tape,
providing that both the drive and tape are being used within specification.
Faults are not considered failures when they are related to operator error, mishandling and abuse, system-related faults
(cabling problems, unsupported systems, operating software, and so on), no trouble found, and transportation damage.
2. 3. 11 Mean Time Between Failures
The Mean Time Between Failures (MTBF) for the SDT-10000/SDT-11000 is 250,000 power-on hours, assuming a duty
cycle of 40%, where:
Tape Motion Time
Duty cycle =
Power-on Time
12.5% is assumed as a typical usage level.
2. 3. 12 Mean Time To Repair
The Mean Time To Repair (MTTR) of the SDT-10000/SDT-11000 is 30 minutes. Since at the field level the entire drive
is considered a Field Replaceable Unit (FRU) the time to replace the drive with a new one is less that 30 minutes.
-15
× 100
SONY SDT-10000/SDT-11000 DDS Tape Drive
. For further details, refer to "Designing a Data Storage
2 - 7
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