Eaton STS 2000A, Инструкция по установке и эксплуатации

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Eaton Static Transfer Switch 2000A 3-Pole Installation and Operation Manual 164001127—Rev 01 19
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Grounding is primarily for equipment and personnel safety, although proper grounding also enhances
equipment performance. Improperly grounded systems can not only create unsafe conditions, but also
electrical noise that can cause data processing and transmission problems.
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The system includes a computer grade single-point ground in accordance with FIPS Pub 94 and the
requirements of the NEC. (See
Figure 8 ), STS 2000A 3-Pole One-line Diagram.)
All input and output power feeds must include an equipment grounding means as required by the NEC and
local codes.
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In addition to the power grounding system, a reference grounding system for high frequency noise is desirable
(with the two systems being bonded together for the same reference potential). A grid made up of 2-foot
squares will provide an effective signal reference grounding system. The raised floor can be utilized if it has
solidly connected metal stringers ensuring good electrical connection. If this type of floor is not available, a grid
can be fabricated by laying a mesh (2-foot squares) of braided copper strap directly on the concrete sub floor
(electrically connected at each intersection point). The frames of all the data processing equipment, including
the STS, should be connected (by the shortest possible distance) to the reference grid with braided copper
strap. Finally, the signal reference grid should be bonded to the WaveStar for a single point equipotent ground
reference
For optimum performance all distances for power and high frequency grounding should be kept to an absolute
minimum. To summarize, a radial grounding system of this type (utilizing a single ground point) will insure that
your facility is electrically safe, complies with all code requirements, and will be essentially free of ground
caused computer noise and problems.
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The STS 2000A has input source and bypass MCCBs that are 100 percent rated for 2000A, the full load rating
of the unit. Consequently the STS 2000A does not itself need upstream circuit breaker protection. However,
customers should provide circuit breaker protection for the input wires to the STS as required by the NEC.
For additional information, refer to your local codes and the National Electric Code (NEC).
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By default there is one isolation MCSW. The customer can specify a second isolation MCSW to provide a
redundant MCSW at time of order.
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The two input feeds for the STS should be from separate and independent sources to avoid a common source
failure. The input feeds should nominally be of the same voltage and phase rotation. The input power wire size
should be based on the upstream over current protection device, observing NEC and local codes.
If the sources are temporarily fed from a common upstream feeder, the unit should be put in bypass until two
separate source feeders are available.
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All power wiring and control wiring must comply with NEC and applicable local codes, including power
connections to the input and output buses.
Input power and load cabling connections are through the top or bottom of the unit ( Figure 4 ).
Installation Planning