S&C Vista SD Underground Distribution Switchgear is solid-dielectric switchgear that features load interrupter switches and fault interrupter switches for switching 600A and 200/600A circuits respectively. It is considerably smaller than traditional air-insulated gear and is suitable for subsurface vault installation. It utilizes vacuum interrupters and manual operating mechanisms, and optional motor operators are available for remote operation. Terminals have field-replaceable bushings and the overcurrent control can be programmed using a PC.

1. April 13, 2015
© S&C Electric Company 2014-2015, all rights reserved Photo Sheet 695 -700
S&C Vista® SD Underground
Distribution Switchgear
Outdoor Distribution (17.5 kV and 29 kV)
With Visi-Gap™ Load-Interrupter Switches
and Visi-Gap™ Fault Interrupters — Vault
Installation Style
S&CVistaSDUndergroundDistributionSwitchgearfeatures
load-interrupter switches for switching 600-ampere main
feeders, and microprocessor-controlled fault interrupters
for the switching and protection of 600-ampere main feeders
and 200- or 600-ampere taps, laterals, and sub-loops. These
elbow-connected components are encapsulated in an
environmentally friendly solid-dielectric insulating material.
Vista SD Switchgear is available in ratings through 29 kV
and 16 kA symmetrical interrupting.
Vista SD Underground Distribution Switchgear is
considerably smaller than traditional air-insulated gear; it
can be installed exactly where it’s needed. It’s completely
submersible and thus suitable for installation in subsurface
vaults subject to flooding. Single-way Vista SD assemblies
are ideally suited for application on the primary side of
network transformers. Multi-way assemblies, from three
to six load-interrupter switches or fault interrupters, are
also available.
Single-wayVista SD switchgear is ideally suited for use on
the primary side of network transformers. Model 101
(fault interrupter) shown.
Multi-wayVista SD switchgear can be used in submersible
vaults with multiple source ways and/or multiple
protected ways (taps).
S&C Visi-Gap load-interrupter switches utilize a vacuum
interrupter in series with a manually operated two-position
isolating disconnect, for three-pole live switching of
600-ampere three-phase circuits. Load-interrupter switches
comply with IEEE Standard 1247 and IEC Standard
62271-103. They feature an easy-to-operate manual
operating mechanism.
S&C Visi-Gap fault interrupters utilize a vacuum
interrupter in series with manually operated two-position
isolating disconnect, for three-pole load switching of 200- or
600-ampere circuits and fault interrupting through 16 kA
symmetrical at 17.5 kV and through 12.5 kA symmetrical at
29 kV. Fault interrupters comply with both IEEE Standard
C37.60 and IEC Standard 62271-111.
Load-interrupter switches and fault interrupters can
be directly opened and closed using the manual handle
furnished. Opening and closing speed is not dependent
upon the speed with which the handle is moved. Operating
shafts are padlockable in either position.
Introducing the industry’s f irst practical solid- dielectric switchgear
with a visible open gap and f ield- replaceable bushings

2. S&C Vista® SD Underground Distribution Switchgear
Load-interrupter switches and fault interrupters can be
directly operated using the manual handle provided, or
from the side using a rope,or with a shotgun stick.
Factory-installed and wired motor operators, to facilitate
remote power operation of load-interrupter switches and
fault interrupters, are optionally available. They can be
decoupled from the operating mechanisms to permit testing
without changing the positions of the switches or fault
interrupters. The motor operators require a user-furnished
100-240 Vac 50/60-Hz control power source.
Motor operators can be factory- or user-installed and
facilitate remote operation of load-interrupter switches
and fault interrupters.
The motor operators are controlled by an accessory
cable-connected (25- or 50-feet length) portable remote
control pendant, featuring “Open/Reset” and “Close”
push buttons, operator- and isolating-disconnect position-
indicating lamps, and lamp test button. The portable remote
control pendant is fully submersible.
Easy-to-follow mimic bus and indicators on the front of
the switchgear convey the positions of the load-interrupter
switches and fault interrupters (and their isolating
disconnects), and if a fault interrupter has tripped on a
fault. The default color scheme is green for “Open/Reset”
and red for “Closed.” To reverse these colors (i.e., green
for “Closed” and red for “Open/Reset”), specify Catalog
Number Suffix “-J1.”
Mimic bus and indicators convey positions of load-
interrupter switches and fault interrupters (and their
isolating disconnects).
Large viewing windows provide a clear view of the
isolating disconnects, allowing operating personnel to
easily confirm the positions of load-interrupter switches
and fault interrupters.
Open Closed
Visible open gap provided by isolating disconnect is
easy to see through large viewing windows.
Terminals are equipped with field-replaceable
600-ampere-rated bushing adapters. Fault interrupters
may be optionally equipped with 200-ampere bushing well
adapters in lieu of 600-ampere bushing adapters. Bushing
and bushing-well adapter interfaces conform to IEEE
Standard 386, and accept all standard insulated connectors
and inserts.
Theself-poweredovercurrentcontrolcanbeprogrammed
using a personal computer connected to the control through
an adapter cable. The control features a variety of fuse and
relay time-current characteristic (TCC) curves that comply
with IEEE Standard C37.112.
2 S&C Photo Sheet 695-700

3. S&C Vista® SD Underground Distribution Switchgear
Ratings: IEEE IEC
kV,System Class 15 27 12 24
kV,Maximum 17.5 29 12 24
kV,BIL 95 125 75 125
Amperes,Continuous,Main Bus 600 600 630 630
Load-Interrupter Switches
Amperes,Continuous 600 600 630 630
Amperes,Load Splitting and Load Dropping❶ 600 600 630 630
Amperes,RMS,Symmetrical Momentary and One-Second 16 000 16 000 16 000 16 000
Amperes,RMS,Symmetrical Fault Closing,ThreeTime❷ 16 000 16 000 16 000 16 000
Fault Interrupters
Amperes,Continuous❸ 600 600 630 630
Amperes,Load Splitting and Load Dropping❶❸ 600 600 630 630
Amperes,RMS,Symmetrical,Interrupting 16 000■ 12 500 16 000■ 12 500
Short-Circuit Rating
Amperes,RMS,Symmetrical 16 000■ 12 500 16 000■ 12 500
❶ Parallel or loop switching.
❷ Applicable to fault closing into closed position.
❸ 200 amperes if fault interrupters are furnished with optional 200-ampere bushing wells.
■ 12,500 amperes if fault interrupters are furnished with optional 200-ampere bushing wells.
Ground bus
(optional)
Visible open gap
(isolating disconnect)
is easy to see through
large viewing windows
Parking stands
(optional)
600-A bushing
adapters
are field replaceable
Overcurrent
control
Operating mechanism
Voltage indication
feature (optional)
CT
Vista SD Switchgear has the features and options needed to match user needs. Wet-vault mounted style shown with
cables at top,operating mechanism at bottom (Catalog Number Suffix“-V1”).
S&C Photo Sheet 695-700 3