Sun Microsystems Sun Fire 12K, Руководство по планировке объекта

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3-6 Sun Fire 15K/12K Systems Site Planning Guide • June 2003
3.2 Cabinet Grounding Requirements
The Sun Fire 15K/12K systems achieve earth ground through the power cords. For
this reason, a gounding cable is not provided with the system. The power cords have
three prongs: two for current and one for ground. At the AC input module, the
ground prong, and system chassis are connected. Final chassis ground is achieved
when the power cord is connected to a receptacle, where the ground prong contacts
the power receptacle. For successful grounding, the customer must provide properly
grounded power receptacles so the power distribution unit (PDU) ground is earth
ground.
A ground cable may be affixed to the system. While not required, the additional
ground point allows leakage current to dissipate more efficiently. It is important to
note that power cords are grounded through the receptacle and the ground cable
must reference a common earth ground. Otherwise, a difference in ground potential
can be introduced.
Caution –
If the customer is unsure of the facility PDU receptacle grounding,
do not install a ground cable until a proper PDU receptacle grounding has been
confirmed. If a difference in ground potential is apparent, corrective action must be
taken .
Use the following procedures to properly ground the Sun Fire 15K/12K systems.
Note – You can use the A-series circuit breaker (Carlingswitch, part number:
AF3-X0-06-184-X13-D, or equivalent) if a PDU is used between the Sun Fire 15K/12K
systems and the facility power system.
TABLE 3-3
Power Configuration Summary
Configuration
Protection From Loss of
Internal Power Supply Protection From Loss of
External Source of Power
Redundant (
FIGURE 3-1
) Yes Yes, one of two sources
High reliability (
FIGURE 3-2
) Yes No, only one source
Basic ( FIGURE 3-3 ) Yes No, only one source