GE Industrial Solutions Zenith User Manual

GE Energy

Digital Energy

Zenith Energy Commander

Paralleling Switchgear

PB-2102 • Page 2

Paralleling Switchgear (PSG)

Paralleling is an operation in which multiple power
sources, usually two or more generator sets, are
connected and synchronized to a common bus
(same parameters in regards to frequency, phase
angle, etc.).

Why Parallel?

There are several advantages to be realized when
employing paralleling switchgear in an electrical
design such as increased reliability, flexibility, ease of
uninterruptible maintenance and application/operation
cost savings. It is because of these advantages that
paralleling switchgear has become one of the best
choices for meeting today’s power requirements.

Why GE Zenith Energy Commander?

GE’s Zenith Energy Commander has been providing

customer facilities with reliable power switching systems
for many years and continues its excellence today.

Since the inception of paralleling switchgear, many
successful Energy Commander installations have
been supplied with a focus on providing reliability.

GE’s Zenith Energy Commander has become the

leader in supplying solutions to simple and very
complex systems due to its design flexibility.

GE’s Zenith Energy Commander has evolved and

adapted to the changing technologies in engine
generator design, switchgear controls and monitoring
systems. It reflects GE’s continuing commitment to
reliable solutions for critical power applications.

Uptime

Systems in which part of the load is very critical may
be best served by paralleling one or more generator
sets. Under parallel operation all the generator sets
are started at once. The first set to reach the proper
parameters will assume the most critical portion of
the load, with the remaining sets picking up lower
priority loads. In addition, by using a load shedding
application, the failure of one generator set will not
interrupt power to the critical loads, as less important
loads can be dropped off the line.

Flexibility

Paralleling power sources allows for a wide variety
of choices in the generation, distribution and utilization
of the system’s power.

Capital Cost Savings

Savings can be realized on the application when a
number of smaller generator sets would be less
expensive than one large set or when the load
makes it impractical to divide into several sections,
each with it’s own generator.

Operational Cost Savings

Savings can also occur on the operation side when
generator set life is extended from being used only
when needed to support the load. Also, when it is
anticipated that the load will grow significantly in the
future, the capital investment can be reduced by
starting with small sets and paralleling additional
units as load increases dictate.

Uninterruptible Maintenance

When one engine - generator set is out of service for
maintenance or repair, having others synchronized
on the same bus can provide the needed back-up
power, should an outage occur.