Fujitsu MCJ3230SS, Руководство по эксплуатации продукта

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Specifications
2-6 C156-E224-01EN
2.1.4 Error rate
Data blocks to be accessed are evenly distributed on the disk. Errors due to disk
defects are not included.
(1) Bit error rate after ECC processing
The error rate after ECC processing must be 10
-12
or less. An optical disk cartridge
whose raw error rate is 10
-4
or less should be used.
(2) Positioning error rate
The positioning error rate must be 10
-6
or less. (with retry)
2.1.5 Reliability
(1) Mean time between failures (MTBF)
The MTBF is 120,000 hours or more. Failure due to disk errors is not included.
Conditions
•
Power-on time: 200 hours/month or less
•
LD-on time: 20% or less of power-on time
•
Environment Temp.: 25°C
Note:
The MTBF is defined as follows:
- Operating time is the total time power is applied.
- Device failures indicate that devices require repair, readjustment, or
replacement. Failure due to external factors such as minor defects
during device handling, operation outside environmental
specifications, power failure, host system errors, and interface cable
errors are not included.
(2) Service Life
Under appropriate handling and operation, disk cleaning and optical head
cleaning, overhaul of the drive is not required for the first five years.
(3) Data security at power failure
Except for the data of the block to which write operation is in progress, all data on
the disk is secure from power failure. This does not apply if power failure occurs
during disk initialization (formatting) or defect processing (alternate block
allocation).
total operating time in all fields (hours)
MTBF=
number of device failure in all fields