User's Manual

12
DAT 72/DDS-4 Product Manual
Environmental Requirements
The following table lists the environmental specifications for DAT 72 and DDS-4
drives. The internal drive should meet these standards if mounted either vertically
(on its side) or horizontally (right side up).
Specification
Operational
Nonoperational
Temperature
+41
o
to +113
o
F
1
(+5
o
to + 45
o
C)
–40
o
to +149
o
F
2
(–40
o
to + 65
o
C)
Thermal gradient
2
o
C per minute
(no condensation)
Below condensation
Relative humidity
20% to 80%
noncondensing
1
0% to 90%
noncondensing
2
Maximum wet bulb temperature
82.4
o
F (28
o
C)
No condensation
Altitude
–100 to +4,575 meters
–300 to +15,200
meters (power off)
Vibration
1.20 mm peak-to-peak
1.5 g (5 to 500 Hz)
Sweep Test
(5–17 HZ)
0.73 G peak (17 to 150 Hz)
0.50 G peak (150–500 Hz)
(sweep rate 8 decades per
hour)
—
—
—
Acoustic level idling (A-wt sum)
47 dBA maximum
0
Acoustic level operational
(A-wt sum)
53 dBA maximum
0
Shock (1/2 sine wave)
10 Gs peak, 11 msec
100 Gs peak,
11 msec
1. Mechanism and media 2. Mechanism
Reliability
The DAT 72 and DDS-4 drives are designed for maximum reliability and data
integrity. The following table summarizes the reliability specifications.
Specification
Value
Nonrecoverable error rate
< 1 in 10
15
bits
Error recovery and control
Error-correction code techniques (C1, C2, & C3 ECC)
Read-after-write (RAW)
DDS:
N
-Group writing (DDS-2 mode only)
Error monitoring and reporting (error log)
Retry on read
Data randomizer
Track checksum
Mean time between failures
(MTBF)
412,000 hr at 20% duty cycle
Mean time to repair (MTTR)
Less than 0.5 hour