Fujitsu MCJ3230SS manual Error rate, Mtbf=

Specifications

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 10-12or less. An optical disk cartridge whose raw error rate is 10-4or less should be used.

(2) Positioning error rate

The positioning error rate must be 10-6or less. (with retry)

2.1.5Reliability

(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:

total operating time in all fields (hours)

MTBF=

number of device failure in all fields

-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).

2-6 C156-E224-01EN