Product Lifetime; Battery Replacement; Regular Replacement - NEC M310 Configuration Manual

5. Functions < Product Lifetime>

Product Lifetime

The wear/lifetime of the product is defined for the hardware stable operation in M-Series. When
purchasing NEC products, it is recommended to review the wear/lifetime specifications and
replacement costs. Note that It may be necessary to replace components for stable operation prior to
the following lifetime depending on components..
Lifetime of
Regular Replacement Component
Lifetime of Consumables

Battery Replacement

The NEC Disk Array Unit performance is enhanced when write-cache is on. The battery power is used
to retain the data on cache when an unplanned disconnection such as a power outage occurs. The
battery power is consumed while the disk array is running. It is necessary to replace the battery in
about 5 years*. This replacement can be done while the system is running.
* The lifetime of the battery is shortened when it is used at high temperature. Whereas it is about five
years at an ambient temperature of 25ºC (77ºF), it decreases to about half (two years and six
months) when the ambient temperature rises 10ºC (18ºF). As the frequency of battery backup
increases, the lifetime of battery decreases. This lifetime above is calculated considering only an
unplanned power disconnection such as power outage.

Regular Replacement

The hard disk drive and fan for power supply has mechanicals parts(wearing parts). If over 7 years
operation is requested, regular replacement is needed at 5 years after operation is started. 5-year
regular replacement is only one time in the whole product lifetime.
As for Nearline SAS HDD and SAS SSD, regular replacement at 5 years is strongly recommended.
Disk Array Unit, HDD, SAS SSD: 5 years
Battery: 5 years
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