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VFI SF6 -INSULATED INSTALLATION, OPERATION AND MAINTENANCE INSTRUCTIONS
MN285004EN October 2015
Electronic control
Line current is sensed by internally mounted current
sensing transformers. When current in excess of the
minimum trip value is detected, the control initiates a signal
which trips the faulted phase or phases, as applicable.
Refer to the applicable Installation and Operation manuals
for control operation and setting procedures.
•
S285-75-1, Tri-Phase Electronic Control, Installation and
Operation Instructions.
Figure 1. Vacuum Interrupter mechanism assembly.
Loadbreak switch
In many configurations Eaton’s Cooper Power series RVAC
switch is integrated within the VFI switchgear. Refer to
Service Information MN285003EN
for operation information
for the RVAC switch.
Vacuum interrupters
Load and fault interruption takes place within sealed vacuum
interrupters (Figure 1). Vacuum interrupters provide fast, low
energy arc interruption and produce no arcing by-products to
contaminate the insulating medium.
Bushings
If 600-amp deadbreak aluminum type bushings are
furnished, they conform to IEEE Std 386™ standard.
200-amp interfaces are provided as either 200-amp bushing
wells or 200-amp one-piece 35 kV bushings; both conform
to IEEE Std 386™ standard.
Bushings are mounted in-line and are located a minimum of
24 inches above the pad.
Cabinet construction
VFI switchgear features deadfront, tamper-resistant,
low-profile construction. It is suitable for operation in
areas subject to excessive moisture, occasional flooding
and blowing snow. Cabinets meet the enclosure security
requirements of ANSI
®
standard C57.12.28.
Swing-up doors are provided with door stays and fitted with
stainless steel hinges. On units wider than 46 inches, split
doors are provided to allow easy operation by one person.
Cabinet style doors can also be provided as an option. Both
source and tap doors can be fully open at the same time.
Each door has a floating lock pocket with padlock provisions
and pentahead silicon bronze door bolt.
Figure 2. VFI fault interrupter components.
Flux Shift
Tripper
Vacuum
Interrupter
Operation One-Line
Diagram
Tri-Phase Control
Bushings
(Shown With
Optional Indicators)
SF
6
Fill Port and
Pressure Gauge,
Located in Source
Side Cabinet (Not
Visible in View)
Recessed Lifting Provisions
Tri-Phase Control
Interrupter Operating Handles
Grounding Lugs
(Not Visible In View)
