NCR RealPOS 7460-2, Дополнительное руководство

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Appendix A:
Transient Protection
AC Power Line Transient Protection
In the process of power distribution, transient electrical energy
(including, but not limited to, lightning strikes, intermittent short
circuits, and switching transients) can be introduced onto power lines.
Such transient energy can be very damaging to electronic hardware,
and can also cause data corruption. Under these circumstances, NCR
recommends the use of AC power transient suppressors. Such
protection devices are intended to guard against power line transients
that can result in hardware damage and various system or program
errors.
Improvement of any deficiencies in power quality is a customer
responsibility. The NCR Maintenance Agreement does not cover
malfunction and/or component failure as a result of power quality
problems. NCR accepts no liability for any such occurrence or for its
consequences.
When power transient suppression is required, the suppressors used
should meet the following minimum requirements:
•
Dissipate energy to match the appropriate application categories as
defined by IEEE Standard 587.
•
Be of the voltage limiting (clipping), or tracking filter type. The
suppressor must not clamp the voltage to zero, and must self-
recover after the passage of the transient. The suppressor may be of
the hybrid type construction that makes use of various technologies
in order to meet speed and dissipation requirements.
•
Upon failure, exhibit a positive indication of its failure such as a
blown fuse or tripped breaker.
•
Be listed by the accepted safety organization for the country
involved (UL, CSA, VDE, ETL, and so on) and the installation must
conform to local, state, and national electrical codes and
regulations.