MGE UPS Systems EPS 6000, Installation Manual

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During normal operation, the inverter transformer provides
complete electrical isolation between the UPS output to the
attached load and the utility power source input as well as
the UPS battery source.
The static switch transfers the load between the inverter output and the bypass AC source
without interrupting the supply of power to the load, allowing the load to continue operation
while the UPS is being maintained, or in the event of a UPS fault. The static switch circuit
assures that voltage from the UPS output cannot feed back to the utility input lines.
The battery system stores energy for use by the inverter.
The stored energy is utilized in the event that the AC input
power from the utility source fails, or falls outside of acceptable tolerance.
The battery system may be an MGE battery cabinet designed for operation with the EPS 6000
UPS, or a customer-supplied battery installation.
MGE-supplied EPS 6000 battery cabinets may be a provided as stand-alone enclosures, or as
enclosures designed to be mounted adjacent to the EPS 6000 UPS module.
The EPS 6000 battery cabinet comes with a special battery ambient temperature sensor
which allows the optimization of the DC voltage level as a function of the temperature,
ensuring that the battery is properly charged to preserve its longevity.
The static switch cabinet (SSC) provides an electrical path
between the output of the UPS modules and the load.
When the UPS modules are off, the SSC provides power to
the load from the bypass AC input source (mains 2). Up to
six (6) modules can be connected to the SSC, supporting
loads as great as 1,500 kVA. UPS modules may be turned
off individually for maintenance, provided that the remaining
modules can support the load.
The SSC incorporates a static bypass switch and a wrap-around circuit breaker (Q2S); they
connect the load to the bypass AC input source when the UPS modules are off-line. Optionally,
the SSC can be provided with its own maintenance bypass circuit, allowing the SSC and/or
any attached UPS module to be serviced while the load is supplied via the maintenance
bypass AC input source.
This section describes options available for the EPS 6000
UPS. Some configurations do not support some options.
Most options must be specified at the time of equipment order; some options can be installed
in the field. Contact your MGE dealer for complete information.
1.4 Options
1.3 Description of SSC
Major Internal
Components
1.2.5 Battery System
1.2.3 Inverter
Transformer
1 — 24 Introduction
EPS 6000 Uninterruptible Power System