Eaton VacClad-W User manual

Effective December 2010
Supersedes September 2001
Instruction Booklet IB32267ARC
VacClad-W 38 kV arc-resistant
switchgear indoor housings
Contents
Description Page
Receiving, handling, and storing ..............2
Installing indoor switchgear..................4
Adjusting and testing......................12
Operation of the system ...................12
Inspection and maintenance ................13
Lubrication..............................14
Renewal parts ...........................14
A further description of arc-
resistant VacClad-W switchgear .............15
Accessories .............................22
Primary bus joints field
taping procedure (38 kV) ...................25
Read and understand these instructions before
attempting installation, operation, or maintenance
of this equipment. This equipment must be
installed and serviced only by qualified electrical
personnel. Retain this document for future use.
CAUTION
THE SWITCHGEAR DESCRIBED IN THIS BOOK HAS
BEEN DESIGNED AND TESTED TO OPERATE WITHIN
ITS NAMEPLATE RATINGS. OPERATION OUTSIDE
OF THESE RATINGS MAY CAUSE THE EQUIPMENT
TO FAIL, RESULTING IN BODILY INJURY AND
PROPERTY DAMAGE.
PURPOSE
THIS INSTRUCTION BOOK HAS BEEN PREPARED
TO HELP ENGINEERS AND TECHNICIANS INSTALL,
OPERATE, AND MAINTAIN TYPE VACCLAD-W
SWITCHGEAR. FOR INFORMATION ON THE
APPLICATION OF THIS TYPE OF SWITCHGEAR, REFER
TO THE PERTINENT ANSI AND EEMAC STANDARDS,
AND TO EATON’S CONSULTING APPLICATION GUIDE.
DANGER
ALL APPLICABLE SAFETY CODES, SAFETY STANDARDS,
AND SAFETY REGULATIONS MUST BE STRICTLY
ADHERED TO WHEN INSTALLING, OPERATING, OR
MAINTAINING THIS EQUIPMENT.

2
Instruction Booklet IB32267ARC
Effective December 2010
VacClad-W 38 kV arc-resistant
switchgear indoor housings
EATON CORPORATION www.eaton.com
Section 1: Receiving, handling, and storing
indoor switchgear
1.1 Receiving indoor switchgear
The switchgear is shipped to the customer as completely
assembled as possible. Depending on the number of switchgear
vertical sections, it may be necessary to ship the switchgear in
several groups to facilitate handling.
Each indoor switchgear is bolted to wooden skids and covered
with weatherproof material.
VCP-W breakers are shipped in individual containers. See breaker
I.B. 3A74792 for breaker handling instructions.
Each switchgear group and all the cartons and crates are labeled
with the shop order number and a shipping weight. On one of the
groups there will be a shipping packet, securely attached, that
contains the shipping lists, drawings, and so on.
When the switchgear arrives at the installation site, check it to make
sure all the parts described on the shipping list have been received.
Do this before discarding the packing material to prevent losing
parts. If the switchgear has been damaged, file a claim as soon as
possible with the carrier and notify the nearest Eaton representative.
If the switchgear is going to be installed as soon as it has been
received, unpack it and handle it according to the procedure outlined
in the following paragraphs. If the switchgear is to be stored, inspect
it to make sure the shipment is complete and undamaged. Repack
it so it will be protected until it has been installed. (See section on
storage of equipment.)
1.2 Handling indoor switchgear
Table 1 gives the approximate weights of the various combinations
of switchgear and the various ratings of breakers.
The preferred method of handling all switchgear assemblies is by
crane. Lifting members are bolted to the top of each shipping group.
Put a crane hook through each of the four holes to lift and move the
group. After the group has been moved into installation position,
remove the lifting members and discard them. Figure 1 shows the
lifting members for indoor switchgear.
If a crane is not available, move the group into installation position
on rollers. Skids run the length of the group. If the group is to be
skidded sideways, the front and back skids are enough. If it is to
be moved across its depth (from front to back), put in several short
skids across the depth of the group and roll it into position.
ote:N Never maneuver the switchgear directly on the rollers. Always use the
skids to protect the switchgear from being distorted or damaged.
Handle all switchgear whether crated or not crated with great care.
The instrument panels on the front of the vertical sections contain
delicate instruments, relays, and meters that can be damaged by
rough handling. If the switchgear is not put into service right away,
cover it to keep clean. (See section on storage of equipment.)
Figure 1. Handling of Indoor Shipping Group
Arc Pressure
Relief Flaps
Remove and
Discard Lifting
Angles After the
Installation

3
Instruction Booklet IB32267ARC
Effective December 2010
VacClad-W 38 kV arc-resistant
switchgear indoor housings
EATON CORPORATION www.eaton.com
Table 1. Typical Weights (Approximate)
Type VCP-W 38 kV Arc-Resistant Switchgear
Type of Vertical Section Main Bus Ampere Rating Indoor Vertical Section Less Breaker lbs (kg)
Breaker 1200
2000
2500
3000
3500 (1591)
3700 (1682)
4000 (1818)
4000 (1818)
Auxiliary section (no breaker) 1200
2000
2500
3000
3000 (1364)
3200 (1450)
3500 (1591)
3500 (1591)
Type VCP-W Circuit Breaker
Breaker Type Current Ampere Rating Breaker Element Static Weight lbs (kg) Breaker Element Impact Weight lbs (kg)
380 VCP-W 16
380 VCP-W 25
380 VCP-W 32
380 VCP-W 21
600
1200
1600
2000
1070 (486)
1080 (491)
1090 (495)
1140 (518)
1605 (730)
1620 (736)
1635 (743)
1710 (777)
380 VCP-W 40 600
1200
1600
2000
2500
1070 (486)
1080 (491)
1090 (495)
1140 (518)
1240 (564)
1605 (730)
1620 (736)
1635 (743)
1710 (771)
1860 (854)
1.3 Storing indoor switchgear
Packaging for shipping is not suitable for storage. Part of the original
packaging may be discarded when switchgear is removed from the
carrier. Switchgear bus runs, because of their open connection ends,
are particularly vulnerable to moisture and dirt during storage.
If the switchgear must be stored for a while, prepare a suitable storage
space. Keep it indoors in a heated building that is clean and dry. The
floor should be smooth and level to prevent strain and distortion in
the equipment. Be sure the space is well drained so that there is no
standing water. Store the switchgear on its skids to keep it off the
floor and to allow air to move under it freely.
Take steps to prevent the switchgear against dampness, cement
dust, corrosive atmospheres, and extreme temperature changes.
To control condensation, make sure the equipment is well
ventilated. Install temporary space heaters if necessary.
Switchgear should be checked periodically for any signs
of deterioration.
Storing the switchgear outdoors is not recommended. It is the
responsibility of the purchaser to ensure protection during storage.
All spare parts and miscellaneous equipment should be stored with
the same care as the main switchgear.
Summary of storage procedures:
1. Check the ventilation of the switchgear itself and of protective
coverings. Serious damage can result from a non-ventilated
tarpaulin.
2. Check the ventilation of enclosed storage areas of buildings.
3. Check for adequate heat; when in doubt, provide heat.
4. Check for distortion.
5. Check for damage and standing water.
6. Check weather protection including open doors, windows,
drafts, and so on.
7. Do not store outdoors.
8. Inspect periodically.
ote:N For detailed instructions on storing switchgear, refer to Eaton drawing
700B214. A copy of the drawing is attached to each group of switchgear.
1.4 Recommended safety practices
The only people who should be allowed to install, operate, or
maintain this equipment are those who meet the qualification
requirements described in the National Electrical CodeT(NECT).
To perform work on this type of equipment, one must be trained
and experienced in working with high voltage circuits. They should
be familiar with the construction and operation of this equipment
and be aware of the hazards involved.
Before attempting to do any maintenance, always be sure to
de-energize both the primary and the secondary circuits.
Never leave a breaker in an intermediate position in its compartment.
Always crank the breaker into the fully connected or withdrawn position.
Before removing a bolted-on cover, first make sure that all the
circuits have been de-energized.
Never try to disconnect or open the secondary circuit of a current
transformer that is carrying load current. In this situation, the trans-
former develops a dangerous high voltage. Before attempting work,
either de-energize the circuit by opening the breaker or short-circuit
the secondary of the current transformer.

4
Instruction Booklet IB32267ARC
Effective December 2010
VacClad-W 38 kV arc-resistant
switchgear indoor housings
EATON CORPORATION www.eaton.com
Section 2: Installing indoor switchgear
2.1 Outline of installation procedure
1. Prepare the installation foundation. It is recommended that floor
channels be embedded in the foundation to maintain a level surface.
2. At the factory, the switchgear lineup may have been divided
into groups to facilitate shipping. At the installation site, the
groups must be rejoined to form the switchgear lineup. Align
the groups, side-by-side, using the tie-bolt holes.
3. Bolt the groups together through the tie bolt holes.
4. Bolt or weld the base members of the vertical section frame,
front and rear, to the foundation channels.
5. Remove all shipping braces.
6. Connect the ground bus.
7. Connect the high voltage bus between the shipping group.
8. Connect the control wires.
9. Replace the metal barriers in the bus compartments.
10. Connect the main power cables and fully insulate the terminals
for the voltage class (see section on storage of equipment).
11. Replace the rear covers on all the vertical sections.
12. All 38 kV arc-resistant switchgear assemblies require an arc skirt
assembly to be installed above the roof of the switchgear for arc
expulsion containment.
13. Check the operation of the levering-in system in the breaker
compartments.
14. Check the potential transformers and the control power
transformers in the auxiliary compartments.
15. Perform loading check on both control and primary circuits to
ensure that the system is ready for operation.
2.2 Details of the installation
1. Prepare the foundation.
Review the floor plan drawings supplied for the order and the
following instructions carefully.
a. The minimum recommended clearances at the front, rear,
and sides of the switchgear are shown in Figure 2. Locate
the foundation so there is adequate space at the front, rear,
and sides of the switchgear lineup. Leave at least 6.6 feet
(2m) of unobstructed space above the roof of the switchgear
for arc expulsion. When applicable, an arc skirt is installed
within this space. No electrical equipment should be located
above the switchgear without proper protection suitable to
withstand arc expulsion.
b. Make sure that the foundation is flat, level, and in true plane.
c. Design the foundation so it will be strong enough to support
the weight of the switchgear without sagging. Table 1 gives
the weights of the various ratings of switchgear and breakers.
Be sure to take into account the shock or impact weight
that occurs when the breaker trips and when it closes.
The impact weight is 1.5 times the weight of the breaker.
The weights in the tables are only an approximation. The
actual weight will vary, depending on the type and the
amount of equipment in the switchgear. Use adequate
safety factors.
d. The recommended foundation consists of steel channels
embedded in a level concrete floor. The channels must lie in
a flat and level plane. A slope of 0.125 inch (3.175 mm) in 3
feet (0.9m) in any direction is acceptable. In no case may the
non-supporting areas of the foundation be higher than the
tops of the steel channels.
The anchor bolts, channels, and other materials are to
be furnished by the purchaser of the switchgear. A
4.00-inch (101.6 mm) structural channel is recommended
as the minimum size for the average indoor switchgear system
If unit substation transformers or high voltage switches
are part of the installation, be sure that the floor steel
under the transformer conforms to the specifications of
their manufacturers.
e. Install the conduits in the foundation.
When the primary and secondary cables enter the switchgear
from below, the conduits that carry them are embedded in
the foundation. A floor plan drawing is furnished with each
order. Use this drawing to determine the conduit locations.
Avoid circling of steel around single-phase cables rated 600A
or more to prevent overheating due to induced currents.

5
Instruction Booklet IB32267ARC
Effective December 2010
VacClad-W 38 kV arc-resistant
switchgear indoor housings
EATON CORPORATION www.eaton.com
Figure 2. Typical Indoor Base Plan
2. Align the shipping groups side-by-side on the foundation.
a. Remove the crating and packaging material from the groups
of switchgear that are going to be installed.
b. Let the shipping skids remain on each group until the group
has been moved into its final installation position. (The skids
help to protect the switchgear and to reduce the risk that it
will be damaged or distorted during the move.)
c. If an odd number of groups are to be installed, install the
middle one first. Then install the other groups, working out
from the middle.
If an even number of groups are to be installed, start with a
group on either side of the middle shipping break.
If a unit substation or a power center is being installed, line
up the power transformer and the adjacent switchgear group
first. Set them in the position called for on the drawing of the
base plan. Then install the rest of the groups.
d. Handling the switchgear by crane is the preferred method.
If no crane is available, the groups may be moved on the
skids and rollers.
Move the first group into position. Line up the bolt holes in
the base of the vertical sections with the bolt holes in the
steel channels in the foundation.
A few inches in front of the lineup, draw a baseline along
the length of the intended location of the switchgear. As the
groups are maneuvered into place, keep the front of each
group parallel to the baseline.
e. A bolt at each end of the wooden skids holds them to the
base of the group. Lift and remove the bolts, and discard
the skids.
f. Set the group into its installation position. Use a level to
make sure the group is level across its depth and along its
length. Use a plumb line to make sure the group is plumb.
(To level or plumb the group, use shims at the points where
the vertical sections will be bolted to the floors.)
Move each group into position and repeat the preceding
steps.
3. Bolt the groups together through the tie bolt holes.
a. Open rear doors (or remove rear covers) of the cells on side
of the shipping split. Install tie bolts between the shipping
splits. Refer to Figure 3 for the tie bolt locations. There are
five tie bolt locations at the rear of the rear-module. There are
four tie bolt locations at the rear of the mid-module. After all
tie bolts are installed, tighten the bolts.
b. Refer to Section 8.3 for instructions for breaker compart-
ment door. Open all front doors. Insert and tighten tie bolts
between the front upright members at each shipping split.
There are five tie bolt locations at the front and one location
at the rear of the mid-module. There are five tie bolt locations
at the front and two locations at the rear of the front-module.
( ) = Diagram dimensions in mm
a Anchor locations: indoor—0.5–13 inch bolts or weld, outdoor—0.5–13 inch bolts.
b Secondary conduit space: All—maximum of 1.00 inch (25.4) projection.
c Recommended minimum clearance to front of VacClad-W: 84 inches (2133.6).
d Recommended minimum clearance to LH or RH side of VacClad-W: 38 inches (965.2).
e Recommended minimum clearance to rear of VacClad-W: 42 inches (1066.8).
f Station ground connection provision.
g Finished foundation surface (including floor steel) must be flat and level and in true plane
h Primary conduit area for top or bottom entry.
i 4 inch (102 mm) channel

6
Instruction Booklet IB32267ARC
Effective December 2010
VacClad-W 38 kV arc-resistant
switchgear indoor housings
EATON CORPORATION www.eaton.com
4. Check the entire lineup to make sure it is level and plumb prior
to bolting or welding to the foundation channels.
5. Remove all shipping blocks or braces.
a. Remove shipping braces from CT bushings in the main bus
compartment and CT spouts in the cable compartment.
b. Examine all meters, relays, and so on, and remove any
shipping blocks or braces. Remove lifting angles from top
of the units and discard them.
6. Connect the ground bus.
a. The ground bus in the switchgear is assembled in sections.
There is a joint in each housing. Solderless terminals are
provided on the ground bus in each end unit. Use these
terminals to connect the ground bus to the station ground.
Make the connection as direct as possible. It should be large
enough to carry the ground fault current of the installation.
Never house it in a metal conduit.
b. The standard ground bus is a 0.25 inch (6.4 mm) x 2.00 inch
(50.8 mm) copper busbar bolted to the cross members of the
frame in the bottom of each enclosure. The ground bus runs
through the center of each section through the length of the
entire switchgear system. Where the system is split for
shipping, a splice plate (and hardware) is furnished to
bridge the shipping break when the system is installed.
Refer to Figure 4.
ote:N The importance of adequate grounding cannot be overstressed. For
the design and installation of a grounding system, refer to electric power
distribution for industrial plants (IEEETSTD. 141); grounding of industrial
and commercial power systems (IEEE STD. 142); and the National
Electrical Code, Articles 100, 200, and 250.
For generating stations and larger substations, the ground resistance should
be 1 ohm or less. For industrial plants and small substations, the ground
resistance should be less than 5 ohms. (The National Electrical Code states
that the ground resistance should never exceed 25 ohms.)
Figure 3. Tie Bolt Locations
Figure 4. Ground Bus Installation
Ground Bus
(Rear View)
Ground Bus
Extension
(Rear View)

7
Instruction Booklet IB32267ARC
Effective December 2010
VacClad-W 38 kV arc-resistant
switchgear indoor housings
EATON CORPORATION www.eaton.com
7. Connect the high voltage bus between the shipping groups.
a. Remove the horizontal metal barriers from the cable
compartment in the rear of the switchgear. Remove the
bus barrier. Also remove any other components such as
potheads, surge suppressers, and so on, that interfere with
access to the bus compartment.
ote:N Rear assembly of switchgear may vary. Figure 5 and Figure 6 show
the removal of necessary barriers (typical).
b. Obtain the section of bus that was removed to separate the
groups for shipping. Each section is labeled and shipped in
the carton with the details.
c. The surfaces in the bus joints are silver-plated. Clean the
plated surfaces of the bus section if necessary.
d. Slide the section of main bus through the supports in the
side of the vertical section. Slide the rubber snubber along
the bus until it fits inside the opening in the bus support.
When the bus section is disconnected for shipping, the
splice plates and hardware are left bolted to the end of the
bus in each of the adjoining vertical sections. Sandwich the
end of the disconnected section between the splice plates
and fit the other end of the section between the splice
plates on the end of the bus in the adjacent section. Bolt
the splice plates together on each end of the bus section.
Repeat these steps for each section of bus at each
shipping break.
Torque the bolts in the splice plate to the values shown
in Table 2.
Cover joints with the insulating boots provided. Figure 7 and
Figure 8 show the main bus installation and insulating boots.
Figure 5. Removal of Necessary Barriers
Figure 6. Removal of Necessary Barriers
(Main Bus Shown with Barrier Removed)
Main Bus
Barrier
Feeder Cable
Lugs
T-Boot-Main Bus
1C95090H01
Main Bus

8
Instruction Booklet IB32267ARC
Effective December 2010
VacClad-W 38 kV arc-resistant
switchgear indoor housings
EATON CORPORATION www.eaton.com
Table 2. Bolt Torque Values for Bus Connection
Bolt Size in Inches (mm)
Bolt Material—Torque in Foot-Pounds (Nm)
High-Strength Steel Silicon Bronze
0.25 (6.4) 5 (6.78) 5 (6.78)
0.31 (7.9) 12 (16.27) 10 (13.56)
0.38 (9.6) 20 (27.12) 15 (20.34)
0.50 (12.7) 50 (67.8) 40 (54.24)
0.62 (15.7) 95 (128.82) 55 (74.58)
Figure 7. Main Bus Installation—Dimensions in Inches (mm)

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Instruction Booklet IB32267ARC
Effective December 2010
VacClad-W 38 kV arc-resistant
switchgear indoor housings
EATON CORPORATION www.eaton.com
Figure 8. Insulating Boots
8. Connect the control wires.
a. Reconnect the wiring that was disconnected at the factory
for shipping. The wiring as well as the connecting points
are labeled.
b. Connect the wiring to the remote apparatus and to the
terminal blocks located in the control compartment, or
within the front of the vertical section.
9. Replace the metal barriers and any other parts that may have
been removed to gain access to the main bus compartments.
10. Connect the main power cables.
a. Before connecting a cable, determine its phase. The switch-
gear system is supplied with connections for phasing 1-2-3,
left to right (viewed from the front), unless indicated
otherwise on the shop order drawings.
b. If the two systems are to be paralleled, make sure the phase
rotation and the phase angles are the same. They must be
the same to prevent damaging the equipment. The phase
rotation must conform to the phase rotation on the shop
order drawing so that the instruments, meters, and relays
will operate properly.
c. When forming cables to fit inside the cable compartment,
avoid bending it sharply or kinking it. Make sure it does not
rest on sharp corners or edges that could damage the insulation.
d. Follow the instructions of the cable manufacturer to deter-
mine what minimum bending radii is permitted. Follow the
instructions on insulating the joints so that the insulation will
taper properly through the correct gradient. The insulation
will vary with the type and size of cable, and with the service
voltage for which it was designed.
e. Solderless connectors are usually furnished. The connection
must be insulated according to the recommendation of the
cable manufacturer.
f. If potheads or other types of terminators are furnished,
follow the instructions of the manufacturer when connecting
the cable to them. Use the flexible connectors to connect
the arial lugs to the conductors. This will keep strain off
the insulators of the pothead or the terminator. Tape (or
otherwise insulate) the entire joint (including the flexible
connectors). (See Section 10.)
g. If zero sequence current transformers are used, pass the
power cables through the transformer. Refer to Figure 34
and Figure 35.
11. Replace all metal barriers and secure rear doors (or rear covers)
on all the vertical sections.
Replace all metal barriers, vertical section of the bus barrier,
and any other components removed during hookup of the high
voltage bus. Replace them in a reverse manner from how they
were removed.
Close all rear doors (rear covers) and secure all bolts.
Refer to Figure 9.

10
Instruction Booklet IB32267ARC
Effective December 2010
VacClad-W 38 kV arc-resistant
switchgear indoor housings
EATON CORPORATION www.eaton.com
Figure 9. Assembled Switchgear (Shown with Rear Doors Opened)
CT Spout/Riser
Boot 1C95094G01
CT Bushing Through
Boot—1C95085H01
Incoming
CTs
Feeder
CTs
Auxiliary
Spout Boot
1C95095H01
12. 38 kV arc skirt assembly instructions.
Parts for arc skirt assembly are listed on the parts lists for
the order and supplied detail for field installation on top of the
switchgear lineup. Install the arc skirt assembly as follows.
The following instructions and illustrations show how to assemble
the arc skirts to a 38 kV switchgear enclosure. The arc skirts
are mounted to the roof to provide a degree of protection in
the event of an arc fault inside the enclosure. The arc skirts
are designed to direct the arc byproducts away from personnel
working near the enclosure.
It is important to completely read and to understand the
instructions before beginning any assembly.
Table 3. List of Parts Used
Item Number Description Eaton Number
138 kV front/rear vertical skirt 1C95598H01
238 kV side vertical skirt 1C95598H02
338 kV side vertical skirt-mounting strip 1C95598H04
438 kV vertical skirt seam cover 1C95598H05
538 kV side horizontal skirt 1C95700H02
638 kV middle horizontal skirt 1C95700H08
738 kV end horizontal skirt 1C95700H09
838 kV skirt support 1C95700H06
Step 1: Assembly of vertical skirt mounting strips (Figure 10). Bolt
one vertical skirt-mounting strip (Item 3) to the extreme left roof and
one to the extreme right roof. Use the existing roof bolts to secure
the skirt-mounting strips. Mount as shown in Figure 10.
Figure 10. Assembly of Skirt-Mounting Strips
CT Bushing End
Boot—1C95086G01

11
Instruction Booklet IB32267ARC
Effective December 2010
VacClad-W 38 kV arc-resistant
switchgear indoor housings
EATON CORPORATION www.eaton.com
Step 2: Assembly of the front and side vertical arc skirts (Figure 11).
Important: All vertical arc skirts are mounted with the bent flanges
pointing outward.
Install the front and rear vertical arc skirts (Item 1) with the large
slotted holes to the bottom. Use the existing hardware to bolt the
front and rear vertical arc skirts to the roof.
Mount the left and right vertical arc skirts (Item 2) to the vertical arc
skirt-mounting strip installed in Step 1. Use 0.25-inch (6.4 mm) bolts
with a flat, lock and nut to secure arc skirts to mounting strip.
Attach the seam covers (Item 4) to the inside of every vertical arc
skirt joint. Use 0.25-inch (6.4 mm) bolts with a flat, lock and nut to
secure the seam covers to the arc skirts.
Step 3: Assembly of the front and side horizontal arc skirts (Figure 12).
Important: All horizontal arc skirts are mounted with the bent flanges
pointing upward.
Bolt the front and rear horizontal arc skirts (Items 6 and 7) to the
vertical arc skirts using 0.25-inch (6.4 mm) bolts with a flat, lock
and a nut. Do the same with the side horizontal arc skirts.
Connect the side horizontal arc skirt (Item 5) to the end horizontal
skirt (Item 7) using 0.25-inch (6.4 mm) bolts with a flat, lock and
a nut.
Step 4: Assembly of the skirt supports (Figure 13). Important: All
skirt supports are mounted with the bent flanges pointing downward.
Bolt the arc skirt supports (Item 8) to the underside of the horizontal
arc skirts using 0.25-inch (6.4 mm) bolts with a flat, lock and a nut as
shown in Figure 13.
Space the arc skirt supports at equal distance from one another,
and be sure to install all the arc skirt supports received.
13. Review IB 3A74792, instructions for installation, operation, and
maintenance of Type VCP-W 38 kV vacuum circuit breakers.
Insert the circuit breaker into the respective breaker compart-
ment and check breaker-cell interface interlocks as explained
under Section 4 of IB 3A74792.
14. Check the fused voltage transformer in the auxiliary compart-
ments (refer to Figure 14 and Figure 15).
a. The VT primary fuses are an integral part of the VT. The
fuses are located inside of a fuse tube, located on top of the
VT. The VT(s) and fuse are both mounted on a drawout truck
(see Figure 15).
b. Verify the fused VT compartment front cover interlocks, by
levering the drawer in and out. It should not be possible to
remove the compartment front cover if the drawer is in the
fully connected position or is in between the connected and
disconnected positions. It also should not be possible to
lever the fused VT drawer if the cover is removed.
c. Refer to Sections 8.4 and 8.9 for further description of the
fused VT drawers and interlocks.
Figure 11. Mounting of Vertical Arc Skirts and Seam Covers
Figure 12. Assembly of the Horizontal Arc Skirts
Figure 13. Mounting of the Arc Skirt Supports

12
Instruction Booklet IB32267ARC
Effective December 2010
VacClad-W 38 kV arc-resistant
switchgear indoor housings
EATON CORPORATION www.eaton.com
Figure 14. Typical VT Compartment (Shown with and without
VTs Installed)
Figure 15. Typical VT Drawer Assembly (Shown Removed)
Section 3: Adjusting and testing
1. After the switchgear has been installed and connected to the
apparatus it is to control, give it a final check before it is put
into service. (Make sure the apparatus being controlled is not
connected to the system while the tests are being carried out.)
The testing equipment will depend on the size and the type of
installation. Use portable voltmeters. Use simple devices for
“ringing” or “lighting out” circuits.
2. Examine all wiring circuits to make sure they have not been
damaged or loosened during shipment or installation.
3. Make sure all the connections are correct before the equipment
is operated. “Light out” connections between the switchgear
and remote apparatus such as instrument transformers, auxiliary
switches, and remote control and interlock circuits.
4. Coordinate the settings of the relays with other parts of the
system in accordance with the standards or operating practice
of the purchaser.
5. If the covers are removed from meters, relays, or other devices
for installation or test, handle them carefully. Replace the covers
as soon as possible to keep out dust and dirt.
6. Perform a loading check of the control circuits.
Before energizing the control circuits, check the control bus
with an ohmmeter to make sure there are no short circuits in
the control wiring. If an ohmmeter is not available, connect a
small fuse in series with the source of the control power. This
will protect the control wiring against damage. (The fuse should
be one-fourth the normal rating of the circuit.)
Section 4: Operation of the system
1. Study and be sure to understand the diagrams furnished with
each switchgear system.
2. Install the circuit breaker in the test position. Lift and pull forward
secondary disconnect to engage the control circuit. Check the
breaker operations.
3. A green light on the hinged instrument panel on the front of the
breaker compartment shows the breaker is open. A red light
shows the breaker is closed. In a D-C control scheme, the red
light supervises the trip coil and indicates the trip coil circuit has
continuity. Refer to diagrams supplied for the switchgear for the
control scheme details, indicating light colors, and functions.
4. The details of the breaker control schemes vary from one instal-
lation to another. They comply with the requirements set forth
by IEEE, NEMA, and ANSI. All of the schemes are designed to
coordinate electrically with the mechanical design of the breaker.
VT Compartment
Shutters
VT Secondary
Disconnect
Ground
Connection
VT Drawer
Stop
Viewing
Window
VT Compartment
Front Cover (bolted)
Leaving
Access
VT Compartment Shown Without
Drawout VTs
VT Compartment with VT Drawer and
Front Cover Installed
Top
Mounted
Fuses

13
Instruction Booklet IB32267ARC
Effective December 2010
VacClad-W 38 kV arc-resistant
switchgear indoor housings
EATON CORPORATION www.eaton.com
Section 5: Inspection and maintenance
5.1 Safety precautions
When inspecting, repairing, and performing maintenance on switch-
gear, the fact that dangerous voltages may exist must be kept in
mind. Precautions must be taken to ensure that personnel do not
come in contact with energized high voltage parts. Failure to do
so could result in death, personal injury, or property damage.
1. All connections should be considered energized until the crew
expecting to work on them is ensured that the circuits are
de-energized, and until every possible precaution has been
taken to see that there is no chance of a circuit being
energized while the crew is working.
2. Switches, which have been opened to de-energize a circuit to
permit work on equipment, should be locked or blocked open,
and a suitable visible warning device placed on them.
3. Do not work on parts normally carrying current at high voltage
until these parts have been disconnected and grounded to the
ground bus. The purchaser should make provision for connecting
adequate flexible ground leads to every part of the switching
equipment.
4. A good and reliable ground connection is necessary for every
switchgear installation. It should be of sufficient capacity to take
care of any abnormal condition that might occur on the system
and should be independent of the grounds used for any other
apparatus. Refer to ground bus connections.
5.2 Access to switchgear parts
1. High voltage parts
VacClad-W switchgear is a metal-clad design. All major parts of
the primary circuit are isolated by grounded metal barriers and
enclosed within separate compartments. For example, circuit
breaker, main bus, and primary line and load terminations are
isolated from each other and enclosed in separate compart-
ments, which are made from grounded metal barriers and
covers. Access to high voltage parts can be gained by removing
the covers and barriers. The covers and barriers should not be
removed unless the parts to be exposed are de-energized.
2. Main contacts
Stationary main disconnecting contacts are located behind the
automatic safety shutters.
Upper and/or lower stationary contacts can be exposed by
manually opening the shutters (see Figure 22 and Figure 23).
Do not expose any contacts unless all upper and lower high
voltage parts are de-energized. Failure to do so could cause
death, personal injury, or property damage.
3. Current transformers
Window type current transformers are installed over the
bushings in the rear of the unit (see Figure 24). These CTs are
not easily removable. All primary circuits must be de-energized
prior to gaining access to any CTs.
4. VT primary fuses
Primary fuses are located inside the fuse tube(s), on top of the
VTs. Withdraw the drawer to disconnect position using levering
crank. When the drawer is in the disconnect position, the wind-
ings of the VTs are grounded through the ground fingers on back
of the cover. Verify VT fuse grounding by simply viewing through
the viewing window. Then remove the bolted front cover. The
primary fuses can now be removed by removing ground plate
on end of fuse tube. The VT drawer assembly can also be rolled
out of the compartment if necessary.
5. Control equipment
With the exception of apparatus such as current transformers
and rear mounted heaters, control equipment, and wiring is
generally accessible without exposing high voltage parts.
5.3 Inspection and maintenance schedule
To ensure high-quality service, a definite maintenance schedule,
systematically followed, is essential. Plant, operating, and local
conditions vary to such an extent that the schedule must be
prepared to suit the conditions. However, the following general
requirements should be helpful in setting up the program.
 CAUTION
BEFORE ATTEMPTING ANY INSPECTION OR MAINTENANCE, BE SURE
THAT ALL PRIMARY AND CONTROL CIRCUITS HAVE BEEN DE-ENERGIZED
AND GROUNDED AS REQUIRED, AND THAT PROPER STEPS HAVE BEEN
TAKEN TO BE SURE THAT THEY WILL REMAIN DE-ENERGIZED UNTIL ALL
WORK IS COMPLETED. FAILURE TO DO SO COULD RESULT IN BODILY
INJURY OR ELECTROCUTION. WHEN ENERGIZED, CIRCUIT CARRIES
LETHAL HIGH VOLTAGES.
1. Individual devices
The maintenance schedule for individual devices such as circuit
breakers, relays, and so on, should be based upon recommenda-
tions contained in the individual instruction book for the device.
These operations should be coordinated with the overall
program to result in the least operating inconvenience and
circuit shutdown.
2. Overall installations
The switchgear installation should be given a thorough overall
maintenance check at the end of the first year in service
because it provides an opportunity to evaluate conditions at
an early point in the life of the equipment. Where conditions
are abnormal, more frequent inspection and maintenance is
necessary; where conditions warrant, a longer period of time
between maintenance periods may be used. The following
descriptions 3–13 require attention.
3. Buses and connections
De-energize primary circuits and remove cover plates from
the primary compartments. Before cleaning, take “MEGGER”
readings between phases and each phase to ground. Inspect for
signs of overheating or weakened insulation. Remove dust from
buses, connections, supports, and enclosure surfaces. A vacuum
cleaner with a long nozzle will be of assistance. Wipe clean with
warm water and wipe dry.
After buses have been dusted and wiped clean, take “MEGGER”
readings again between each phase and ground and between
phases. Keep a record of these readings for future reference in
determining when trends occur that would indicate a lowering
of the insulation resistance.
Periodic high potential tests are not required. They are recom-
mended only after repair of high voltage buses or installation, or
when the trend of megger readings indicates it to be advisable. This
field test should be made before the main cables are connected
and should not exceed 60 kV, 60 Hz, for 1 minute. Transformer
primary fuses should be removed and surge protective devices
such as capacitors and arresters disconnected during high
potential tests.

14
Instruction Booklet IB32267ARC
Effective December 2010
VacClad-W 38 kV arc-resistant
switchgear indoor housings
EATON CORPORATION www.eaton.com
4. Primary disconnecting contacts and supports (spouts)
Remove each breaker from its compartment. De-energize
primary circuits and expose primary contacts and their supports
by manually opening automatic safety shutters. Wipe clean
with a cloth moistened in a non-flammable solvent. Inspect for
abnormal wear or overheating. Discoloration of the surfaces is
not harmful unless corrosion due to atmospheric conditions is
severe, leaving deposits on the surface. If necessary, these can
be removed by a light application of crocus cloth. Check each
breaker while it is out of the housing for all items recommended
in the instruction book applying to that particular type of breaker.
(See instruction book 3A74792.)
5. Other disconnecting contacts
Inspect all secondary disconnecting contacts such as those on
drawout transformers for abnormal wear, fatigue, or overheating.
Replace if necessary. Otherwise treat the same as main discon-
necting contacts above.
6. Control contactors
Contacts should be inspected and dressed, or replaced when
the surface becomes pitted. Unless repetitive duty has been
experienced, little attention should be required.
7. Instruments, relays, and other panel-mounted devices
Individual devices should be maintained according to the specific
instructions supplied for each device. Remove all relay covers
and inspect the interiors for dust or dirt. Relay test personnel
can easily perform this operation during periodic relay testing.
8. Secondary wiring
Check all wiring connections for tightness including those at the
current and potential transformers and at the terminal blocks
where circuits leave the switchgear. Make sure that all second-
ary wiring connections are properly connected to the switchgear
ground bus where so indicated.
9. Mechanical parts
Visually check and manually operate mechanical moving parts
such as the shutter, TOC and MOC switch assemblies, the
position interlock, hinged doors, and the drawout features of
the fuse drawers. Examine mechanical mating parts such as
the breaker secondary contacts blocks, guide rails, and trippers.
10. Ventilation
Check all labyrinths, grillwork, and air passages for obstructions
and accumulations of dirt. Check to ensure that all dynamic
flaps (Figure 17, Item 1) are open to allow natural airflow.
These flaps are designed to close automatically during an
internal arcing fault.
11. Battery and charging equipment
The control battery is such an important item in switchgear
operation that it must be given special periodic attention if it
is to give reliable service for a long period of time. Periodic
inspections and tests are recommended in the battery supplier(s)
instructions. At the same time the battery is checked, inspect
the battery charger and remove accumulations of dust and dirt.
On all chargers having a manual transfer switch for setting the
charging rate, check carefully to be sure that the selector switch
is returned to the value appropriate for a floating charge at the
end of the periodic inspection. Serious damage to the control
battery can occur if the charger is left on a high charging rate
for an extended period of time.
12. Records
The condition of each switchgear unit at the time of inspection
should be listed in a permanent record to become a guide for
anticipating the need for replacements or for special attention
between the regular maintenance periods. Megger tests are
suggested for checking the insulation. A series of these tests
will indicate any tendency toward a reduction in dielectric
strength of the insulation. Megger readings should be taken
before and after cleaning the equipment and, where possible,
under similar conditions at successive periods. Records should
include the megger reading, the temperature, and the humidity.
The readings will vary with the extent and design of the bus
structure. In contrast with a small installation, the longer switch-
gear assemblies will have a more extensive bus structure with
a greater number of insulators and thereby, a larger number of
parallel insulation resistance paths to ground which will tend to
decrease megger readings. This variation in insulation resistance
between different switchgear assemblies emphasizes the value
of a series of readings, which can be charted to establish a
normal insulation level so that progressive weakening of the
insulation can be recognized.
13. Abnormal conditions
Local conditions such as high humidity, salt-laden atmosphere,
corrosive gases, heavy dust, or severe circuit operating condi-
tions, are considered to be abnormal. They will require more
frequent inspections.
It should be emphasized that a series of inspections should be
made at quarterly intervals until the progressive facts of the local
conditions can be analyzed to determine a schedule, which will
maintain the equipment in satisfactory condition.
In some locations, conditions may be so bad that the frequency
of maintenance will interfere with operating and production
schedules. In such cases, consideration should be given to the
possibility of enclosing the switchgear equipment in a relatively
tight room and to supplying a sufficient quantity of clean air to
maintain a positive pressure in the room. Under such conditions,
maintenance schedules may then be established on a more
normal basis. Such an arrangement might also provide for
cooling the air where the ambient temperature is relatively
high, thus further improving operating conditions.
Section 6: Lubrication
VacClad-W switchgear is designed so that lubrication is not required
under normal conditions. However, abnormal local conditions such
as high humidity, salt-laden atmosphere, corrosive gases, or severe
circuit-operating conditions may demand the use of lubricants. In
such cases, a dry or powder lubricant should be used on moving
or mating mechanical parts and a thin film of petroleum jelly on
disconnection contacts. The application of the lubricants should
be held to a minimum to reduce the accumulation of dust and dirt.
Section 7: Renewal parts
When ordering renewal or spare parts, include as much informa-
tion as possible. In many cases, the style number of the new part
can be obtained from identification on the old part. Always include
a description of the part. Specify the rating, structure number, and
shop order number of the switchgear housing in which the part is
to be used.

15
Instruction Booklet IB32267ARC
Effective December 2010
VacClad-W 38 kV arc-resistant
switchgear indoor housings
EATON CORPORATION www.eaton.com
Section 8: A further description of
arc-resistant VacClad-W switchgear
Figure 16. Typical 38 kV Arc-Resistant Switchgear Assembly
(Arc Skirts Not Shown)
8.1 Arc-resistant switchgear general discussion
Arc-resistant metal-clad switchgear is metal-clad switchgear tested
for resistance to the effects of arcing due to an internal fault.
The occurrence of arcing inside switchgear produces a variety of
physical phenomena. For example, the arc energy resulting from
an arc developed in air at atmospheric pressure will cause a sudden
pressure increase inside the enclosure and localized overheating.
This results in both severe mechanical and thermal stresses on
the equipment. Moreover, the materials involved in or exposed to
the arc may produce hot decomposition products, either gaseous
or particulate, which may be discharged to the outside of the
enclosure. IEEE guide PC37.20.7, draft 15d, 200X, and EEMAC
standard G14-1, 1987, provide procedure for testing the resistance
of metal-clad and metal-enclosed medium voltage switchgear under
conditions of arcing due to an internal fault. The arc-resistant
switchgear is classified by accessibility types in the two
documents as follows:
IEEE PC37.20.7, draft 15d, 200X—Guide for testing medium
voltage metal-enclosed switchgear for internal arcing faults
Accessibility Type 1
Switchgear with arc-resistant designs or features at the freely
accessible front of the equipment only.
Accessibility Type 2
Switchgear with arc-resistant designs or features at the freely
accessible exterior (front, back, and sides) of the equipment only.
Accessibility Type 1 or Type 2 with Suffix “C”
The application of suffix “C” to Accessibility Type 1 or
Type 2 indicates that the equipment meets the additional
requirements of the Annex given in the standard. It does
not imply that the equipment may be operated with doors,
covers, or panels opened or removed and maintain its intended
degree of protection. This additional performance is intended
to reduce the collateral damage to adjacent compartments
and equipment, and should not be interpreted to indicate
any additional degree of protection for personnel. Equipment
qualified to the conditions described is labeled as Type 1C or
Type 2C (as appropriate).
Type 1C—Type 1 equipment subjected to additional testing and
assessment to verify that the internal arcing does not cause
holes in the freely accessible front of the enclosure or in the
walls separating the compartment in which the arc is initiated,
and all adjacent compartments.
Type 2C—Type 2 equipment subjected to additional testing and
assessment to verify that the internal arcing does not cause
holes in the freely accessible front, sides, and rear of the
enclosure or in the walls separating the compartment in which
the arc is initiated, and all adjacent compartments. Exception:
In metal-clad (C37.20.2) equipment, a fault in a main bus bar
compartment of a vertical section is allowed to propagate into
the main bus bar compartment of the adjacent vertical sections
if the main bus bars are in the same circuit, but not if the main
bus bars are in different circuits. Connections from the main bus
bar to switchgear components are not considered to be part of
the main bus and propagation of a fault along these connections
into the compartment containing the component is not allowed.
EEMAC G14-1, 1987—Procedure for testing the resistance
of metal-clad switchgear under conditions of arcing due to
an internal fault
Accessibility Type A
Switchgear with arc-resistant construction at the front only.
Accessibility Type B
Switchgear with arc-resistant construction at the front, back
and sides.
Accessibility Type C
Switchgear with arc resistant construction at the front, back
and sides and between compartments within the same cell or
adjacent cells. The only exception is that a fault in a bus bar
compartment of feeder cell is allowed to break into the bus bar
compartment of an adjacent feeder cell.
The IEEE standard defines Internal arcing short-circuit current as the
maximum value of the rms symmetrical prospective current applied
to the equipment under conditions of an arcing fault for the arcing
duration specified by the manufacturer. The preferred value of the
internal arcing short-circuit current is the rated short-time current of
the equipment. The preferred arcing duration is indicated as 0.5 sec-
onds at the rated power frequency of the equipment. A single test is
done to verify resistance of switchgear against pressure as well as
burn through. The actual values (which may be higher or lower than
the preferred values) of the internal short-circuit current and arcing
duration are specified by the manufacturer on the equipment
ratings nameplate.
In EEMAC standard, internal arc short-circuit current is indicated as
the prospective short-circuit current applied during the calibration
prior to testing and may be equal to or lower than the rated short-
time capability of the equipment. This standard requires testing to
prove resistance of switchgear against pressure (arcing duration
10 cycles), and testing to prove the resistance of switchgear to
burn through (arcing duration 1 second).
There are also differences in the two standards in the way test-
ing is conducted and assessed. It is not possible to list differences
between the two standards in this instruction book. Refer to the
drawings supplied for the equipment for internal arc short-circuit
current, duration, accessibility type, and standard to which the
equipment is tested. User should then refer to the applicable
standard for details of guidelines under which the equipment
is tested and qualified.
Door Handle
Open Position
Door Closed
Open Position

16
Instruction Booklet IB32267ARC
Effective December 2010
VacClad-W 38 kV arc-resistant
switchgear indoor housings
EATON CORPORATION www.eaton.com
Arc-resistant features are intended to provide an additional degree
of protection to the personnel performing normal operating duties in
close proximity to the equipment while the equipment is operating
under normal conditions. Several conditions must be met for the
equipment to perform as required. These conditions are considered
normal operating conditions for proper application of arc-resistant
switchgear designs and are as follows:
a. All doors and covers providing access to high voltage
components are properly closed and latched.
b. Arc skirt assembly is properly installed on top of the
switchgear, when applicable.
c. Pressure relief devices are free to operate.
d. The fault energy available to the equipment does not
exceed the rating of the equipment (short-circuit current
and duration).
e. There are no obstructions around the equipment that
could direct the arc fault products into an area intended
to be protected.
f. The equipment is properly grounded.
The equipment may be used without additional protection where the
fault level and the fault duration are within the equipment ratings.
When coupled with other protective schemes, selected to operate
within the rated duration of the equipment, the damaging effects
of the arcing fault associated with fault duration can be minimized.
For further review of the nature of internal arcing faults and various
mitigating techniques, refer to application paper, “Strategies for
Mitigating Internal Arc Faults in Medium Voltage Metal-Enclosed
Switchgear,” prepared by Working Group members of IEEE standard
C37.20.7.
8.2 Description of breaker compartment door features
and interlocks
Refer to Figure 17.
1. Shipping brace
Remove the orange shipping brace before breaker is put into
service, but only after the enclosure is in its final and permanent
position. The safety flap must remain open during normal breaker
operation in order to provide adequate ventilation. Do not put a
breaker into service with the safety flap closed. The safety flap
will automatically close in the event of an internal arc. Failure to
remove the shipping brace will prevent automatic closure of the
safety flap during an internal arc.
2. Instrument compartment door
The instrument door must be closed when breaker is in service.
3. Breaker compartment door
All connection and disconnection of the breaker must be done
with the door closed. The breaker door is interlocked with the
breaker to prevent opening of the door while the breaker is
connected. The door can only be opened when the breaker
has been completely racked out to the test position. A second
interlock prevents the racking in of the breaker if the door is
not closed.
4. Safety note
Important note: All doors and panels must be properly closed
and fastened for the arc-resistant feature of the switchgear
to be operative.
Dynamic
Flap
Figure 17. Breaker Compartment Door Features and Interlocks
a Shipping Brace
b Instrument Compartment Door
c Breaker Compartment Door
d Safety Note
e Levering Crank Opening
f Open Pushbutton
g Close Pushbutton
h Sliding Window
i Slot in Window
j Fixed Window
k Phosphorescent Connected Position
l Door Lock Defeat
m Pressure Relief Roof Flaps
n Levering Crank
o Manual Spring Charging Lever
p Door Locking Bolts

17
Instruction Booklet IB32267ARC
Effective December 2010
VacClad-W 38 kV arc-resistant
switchgear indoor housings
EATON CORPORATION www.eaton.com
5. Levering crank opening
The breaker must be connected and disconnected with the
breaker door closed and using the levering crank. With the
door closed, lift the cover to expose the hexagon head of the
levering-in screw. Insert the levering crank and rotate clockwise
to connect the breaker, and counterclockwise to move
the breaker to the test position.
6. Open pushbutton
With the door closed, press the right button to open the breaker
main contacts.
7. Close pushbutton
With the door closed, press the left button to close the breaker
main contacts.
8. Sliding window
This window is used for observing:
• Breaker position—connected or disconnected
• Charging spring status—charged or discharged
• Phosphorescent breaker position indicator (11).
9. Slot in sliding window
Manual spring charging lever is inserted through the slot to
manually charge the breaker springs. A vertical up and down
movement of the lever will charge the breaker springs
(approximately 38 movements are required).
10. Fixed window
This window is used to observe:
• Breaker operations counter
• Breaker contact position (open or closed)
• The phosphorescent marker (see 11)
11. Phosphorescent marker
The phosphorescent marker is only visible through the fixed
window when the breaker is in the connected position and
serves to indicate such.
12. Door lock defeat
The breaker compartment door is automatically locked closed
when the breaker is moved from the test position to the con-
nected position. In case of an emergency, it is possible to defeat
the door interlock while the breaker is in the connected position.
Be aware that by opening the breaker door while the breaker is
in the connected position defeats all safety features of the arc-
resistant switchgear. Remove the nameplate to expose a
spring-loaded locking bar. Push the spring-loaded locking bar
inward until it clears the locking tab on the door. The door can
now be opened.
Important: In order to re-close the door after defeating the
interlock, the levering-in assembly must be moved to the
test position. Failure to do so will prevent the door from
closing properly.
13. Hinge open roof
In the event of an internal arc, the explosion gasses and debris
are projected through the hinge open roof.
14. Levering crank
This crank is used to rack the breaker in and out. The socket is
designed to prevent hot gasses from escaping the front module.
Do not use any other tool to replace the levering crank.
15. Manual spring charge lever
This lever is used to manually charge the breaker. See Item 9 for
more details.
8.3 Opening and closing of breaker compartment door
Figure 18. Opening and Closing of Breaker Compartment Door
To open a closed door, follow the steps below:
1. Open the circuit breaker. Rack it out to the test/disconnected
position.
2. Remove the two bolts located at the left and right lower corners
of the door.
ote:N The door is designed to capture the loose bolts, therefore the bolts
should not be completely removed from the door.
3. Turn handle counterclockwise while lifting up on the grab handle.
The door will slide upward approximately 0.75-inch (19.1 mm).
4. When the door is at its uppermost position, rotate the door open.
Handle in Up
Position
Door Open
Turn Handle
Clockwise
Grab
Handle
Door
Locking
Bolt
Door
Locking
Bolt Door Closed

18
Instruction Booklet IB32267ARC
Effective December 2010
VacClad-W 38 kV arc-resistant
switchgear indoor housings
EATON CORPORATION www.eaton.com
To close an opened door, follow the steps below:
1. Make sure that the breaker is in the test/disconnected position.
2. With the door at its uppermost position, rotate the door closed.
3. Turn handle clockwise while pushing down on the grab handle.
The door will slide downward approximately 0.75-inch (19.1
mm). Make sure the slots in the bottom of the door are
properly aligned with the pins in the floor.
4. Insert and tighten the two bolts located at the left and right
lower corners of the door.
8.4 Fused VT compartment features and interlocks
Fused VTs are mounted on a drawer (Figure 15), which is then
inserted into the VT compartment (Figure 14). The VT drawer is
inserted (manually rolled) into the compartment until it can not be
pushed further. The fused VTs must be in the disconnect position
before inserting the drawer into the compartment. The primary shut-
ter remains closed (Figure 19). To insert the drawer further from
the disconnected position to the connected position, a front cover
(Figure 24) must be bolted in-place. When the cover is in-place and
bolted, an interlock assembly (Item 5 in Figure 24) allows the VT
shutter to open as indicated in Figure 20. After bolting the front
cover in-place, the fused VT drawer can be racked into the
connected position using a levering crank via access port (Item 4,
Figure 24) provided on the front cover. The connected and discon-
nected positions are indicated when the levering screw can not be
turned any further.
The grounding and discharging of primary fuses is accomplished via
grounding contacts (Item 8, Figure 24) provided on the back of the
front cover when the VT drawer is in the disconnected position. The
grounding of primary fuses when the VT drawer is in the discon-
nected position can be verified by simply viewing through a viewing
window provided on the front cover.
When the front cover is bolted-in place, its interlocking assemblies
(Item 5, Figure 24) interfaces with the VT drawer parts to provide
the following interlocks:
a. The front cover cannot be removed unless the VT drawer is
in the fully disconnected position.
b. The VT drawer cannot be moved or racked toward the
connected position unless the front cover is bolted in-place.
The interlocking is achieved as follows (Figure 22 and Figure 23).
• When the VT drawer is in the fully disconnected position, Cover
Lifting Angle (3) disengages Drawer Latch (4) from Stop (2),
allowing drawer to be racked into the connected position, and
Drawer Lifting Angle (5) disengages Cover Latch (1) from Stop
(2), allowing Cover to be removed.
• When the VT drawer is not in the fully disconnected position,
Cover Latch (1) engages Stop (2), preventing the cover from
being removed.
• When the Cover is removed, Drawer Latch (4) engages Stop (2),
preventing racking of VT drawer from disconnected to connected
position.
If it becomes necessary to remove the front cover when the VT
drawer is not in the fully disconnected position, the interlocking
can be defeated by removing the interlock defeat covers (Item 7,
Figure 24), and lifting the Drawer Latch (4) and Cover Latch (1)
from the Stop (2), using a screwdriver or similar tool.
Figure 19. VT Compartment Shown Without VTs, with Front
Cover Removed (Side View)
Figure 20. VT Compartment Shown Without VTs, with Front
Cover Bolted In-Place (Side View)
Figure 21. Fused VT Assembly Shown in Disconnected Position
with Front Cover Removed (Side View)
Figure 22. Fused VT Assembly Shown in Connected Position
with Front Cover In-Place (Side View)
Figure 23. Interlocking Details

19
Instruction Booklet IB32267ARC
Effective December 2010
VacClad-W 38 kV arc-resistant
switchgear indoor housings
EATON CORPORATION www.eaton.com
Figure 24. VT Compartment Front Cover Assembly
8.5 Safety features
Eaton’s VacClad-W switchgear is manufactured with several built-in
interlocks. These interlocks are intended to protect persons working
on the equipment. Never make these interlocks inoperative. Doing
so can damage property and cause severe injury.
The following are two of the interlocks:
Coding plates
A coding plate is fastened to the bottom front edge of the breaker
compartment. There is also a coding plate fastened to the front of
the breaker. If the breaker has a lower interrupting rating than the
rating of the compartment, or if the voltage and continuous current
characteristics don’t match, the coding plate on
the compartment will prevent the entrance of the breaker
into the compartment.
ote:N Even with the coding plates it is possible to put into the compartment
a breaker whose control wiring is not coordinated with that of the compart-
ment. Always check the shop order drawing to make sure that the control
wiring of the breaker and the compartment are the same.
Automatic shutter
An automatic shutter, shown in Figure 25, covers the primary
disconnecting contacts when the breaker is withdrawn from the
operating position. The shutter prevents persons who are working
on the switchgear from accidentally touching the primary contacts.
A roller on the breaker raises the shutter when the breaker is
levered into the connected position. When the breaker is levered
out, the shutter closes by spring action. Each shutter can be
padlocked in the closed or open position manually (see Figure 26).
CAUTION
DO NOT MANUALLY RAISE OR REMOVE SHUTTER UNLESS PRIMARY
CONTACTS ARE DE-ENERGIZED AND SAFETY PROCEDURES HAVE BEEN
INITIATED TO MAKE SURE THE CIRCUIT CAN NOT BE RE-ENERGIZED.
FAILURE TO EXERCISE CAUTION MAY RESULT IN BODILY INJURY AND
PROPERTY DAMAGE.

20
Instruction Booklet IB32267ARC
Effective December 2010
VacClad-W 38 kV arc-resistant
switchgear indoor housings
EATON CORPORATION www.eaton.com
8.6 Ring-type current transformers
The ring-type current transformers are installed over the bus or line
side primary bushings, which are located in the main bus compart-
ment and line compartment, respectively. Maximum numbers of
ring-type CTs that can be installed are as follows:
Bus side bushings: Two sets of standard accuracy or one set of
high accuracy.
Line side bushings: Three sets of standard accuracy or one set of
standard and one set of high accuracy.
The CTs are accessible from the rear of the enclosure only (see
Figure 27). It is not possible to add or to change transformers until
high voltage connections are removed. The polarity marks on the
transformers show the relative instantaneous polarity in the primary
and secondary windings. The diagrams show how to connect the
transformers to give polarity needed to operate relays and instruments.
8.7 Key interlocks
Key interlocks are often supplied in conjunction with disconnecting
switches, dummy elements, and special compartments to which
access is to be denied unless the circuit breakers controlling the
power to these no-load-switching devices have been withdrawn
to the test position. The operation of key interlock schemes is
generally described by a note or keying chart on the shop order
assembly drawings.
CAUTION
TO FACILITATE MANUFACTURE AND INSTALLATION PROCEDURES, A KEY
IS USUALLY SUPPLIED WITH EACH LOCK. BEFORE PLACING SWITCHGEAR
WITH KEY INTERLOCKS IN OPERATION, THE KEY SCHEME MUST BE
CAREFULLY CHECKED; AND ONLY THE PROPER KEYS LEFT IN THE LOCKS.
ALL EXTRA KEYS MUST BE REMOVED AND DESTROYED OR STORED
WHERE THEY ARE NOT AVAILABLE TO OPERATING PERSONNEL. THIS
PROCEDURE IS NECESSARY BECAUSE IMPROPER USE OF SPARE KEYS
WILL DEFEAT THE INTERLOCKING SCHEME.
Figure 25. Breaker Primary Disconnect Shutters
Figure 26. Manual Opening of Shutters (Breaker Compartment)
Figure 27. Ring Type CTs
Primary
Disconnect
Shutters
Manual
Shutter
Latch
Shutter
Primary
Studs
Shutter
Ring
Type
CTs