S&C Alduti-Rupter Switches Outdoor Distribution Owner's manual

Alduti-Rupter®Switches
Outdoor Distribution (25/34.5 kVand 34.5 kV★)
Three-Pole Vertical-Break Style
Reciprocating Operating Mechanism
June 29, 2020
© S&C Electric Company 1977-2020, all rights reserved Instruction Sheet 761-525
Installation and Operation
Table of Contents
Section Page Section Page
Introduction
Qualified Persons ........................... 2
Read this Instruction Sheet ................... 2
Retain this Instruction Sheet. . . . . . . . . . . . . . . . . . . 2
Proper Application .......................... 2
Operating Considerations..................... 2
Warranty .................................. 3
Warranty Qualifications ...................... 3
Safety Information
Understanding Safety-Alert Messages........... 4
Following Safety Instructions .................. 4
Replacement Instructions and Labels ........... 4
Location of Safety Labels ..................... 5
Safety Precautions ......................... 6
Shipping and Handling
Inspection ................................. 7
Packing ................................... 7
Handling .................................. 8
Installation
Mounting to Wood........................... 9
Uncrating the Switch......................... 9
Attaching Couplings to the Switch Poles ......... 9
Mounting the Support Members ...............10
Lifting the Switch ...........................10
Installing Pipe Couplings with Piercing
Set Screws...............................12
Installing the Interphase Pipe ..................13
Installing the Vertical Operating Pipe ............14
Installing the Operating Handle ................15
Checking Alignment .........................17
Installing the Key Interlock ....................18
Checking Operation .........................19
Connecting the High-Voltage Connectors ....... 25
Operation
Opening and Closing the Switch .............. 26
★Also applicable to three-pole vertical-break style switches rated 14.4 kV, 2400 amperes continuous.

2S&C Instruction Sheet 761-525
Introduction
Qualified Persons WARNING
Only qualified persons who are knowledgeable in the installation, operation, and
maintenance of overhead and underground electric distribution equipment, along
with all associated hazards, may install, operate, and maintain the equipment
covered by this publication. A qualified person is someone who is trained and
competent in:
• The skills and techniques necessary to distinguish exposed live parts from nonlive
parts of electrical equipment
• The skills and techniques necessary to determine the proper approach distances
corresponding to the voltages to which the qualified person will be exposed
• The proper use of special precautionary techniques, personal protective
equipment, insulated and shielding materials, and insulated tools for working on
or near exposed energized parts of electrical equipment
These instructions are intended only for such qualified persons. They are not
intended to be a substitute for adequate training and experience in safety
procedures for this type of equipment.
Read this
Instruction Sheet NOTICE
Thoroughly and carefully read this instruction sheet and all materials included in
the product’s instruction handbook before installing or operating your Alduti-Rupter
Switch. Familiarize yourself with the Safety Information and Safety Precautions on
pages 4 through 6. The latest version of this publication is available online in PDF
format at sandc.com/en/support/product-literature/.
Retain this
Instruction Sheet
This instruction sheet is a permanent part of your Alduti-Rupter Switch. Designate a
location where you can easily retrieve and refer to this publication.
Proper Application WARNING
The equipment in this publication is only intended for a specific application. The
application must be within the ratings furnished for the equipment. Ratings and
other application information can be found in Specification Bulletin 761-31.
In most applications, Alduti-Rupter Switches are capable of switching rated continuous
load currents at full voltage. The ratings for the particular switch are listed on nameplates
attached to the operating handle and the switch. See Figure 1 on page 3.
These interrupter switches are not intended for breaking fault currents.
Operating
Considerations
Circuit-making and circuit-breaking is involved in the normal operation of these
interrupter switches, and partial or precautionary opening or closing of the switch should
not be attempted. If the switch is covered in ice or snow, do not "chop" the switch between
the Open and Closed positions to dislodge the ice.
To operate the switch, swing the handle through its full stroke without hesitation. Do
not assume the operating handle position indicates the Open and Closed position of
the interrupter switch blades. After opening or closing the switch, always make a visual
check of the blade position to determine the switch blades are in the intended position.
Then, tag or padlock the operating handle in accordance with standard system operating
practices. In all cases, make sure the operating handle is locked before "walking away"
from the switch.

Introduction
Warranty The warranty and/or obligations described in S&C’s Price Sheet 150, “Standard Conditions
of Sale–Immediate Purchasers in the United States,” (or Price Sheet 153, “Standard
Conditions of Sale–Immediate Purchasers Outside the United States”), plus any special
warranty provisions, as set forth in the applicable product-line specication bulletin,
are exclusive. The remedies provided in the former for breach of these warranties shall
constitute the immediate purchaser’s or end user’s exclusive remedy and a fulllment of
the seller’s entire liability. In no event shall the seller’s liability to the immediate purchaser
or end user exceed the price of the specic product that gives rise to the immediate
purchaser’s or end user’s claim. All other warranties, whether express or implied or
arising by operation of law, course of dealing, usage of trade or otherwise, are excluded.
The only warranties are those stated in Price Sheet 150 (or Price Sheet 153), and THERE
ARE NO EXPRESS OR IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS
FOR A PARTICULAR PURPOSE. ANY EXPRESS WARRANTY OR OTHER OBLIGATION
PROVIDED IN PRICE SHEET 150 (OR PRICE SHEET 153) IS GRANTED ONLY TO THE
IMMEDIATE PURCHASER AND END USER, AS DEFINED THEREIN. OTHER THAN AN
END USER, NO REMOTE PURCHASER MAY RELY ON ANY AFFIRMATION OF FACT OR
PROMISE THAT RELATES TO THE GOODS DESCRIBED HEREIN, ANY DESCRIPTION
THAT RELATES TO THE GOODS, OR ANY REMEDIAL PROMISE INCLUDED IN PRICE
SHEET 150 (or PRICE SHEET 153).
Warranty
Qualifications
The standard warranty is applicable to the Alduti-Rupter Switch detailed in this instruction
sheet except when it is power-operated using a switch operator not manufactured by S&C.
Figure 1. Switch nameplates with ratings.
Nameplate on switch base
Nameplate on operating handle

4 S&C Instruction Sheet 761-525
Safety Information
Understanding
Safety-Alert
Messages
Several types of safety-alert messages may appear throughout this instruction sheet and
on labels and tags attached to your Alduti-Rupter Switch. Familiarize yourself with these
types of messages and the importance of these various signal words:
DANGER
“DANGER” identifies the most serious and immediate hazards that will likely
result in serious personal injury or death if instructions, including recommended
precautions, are not followed.
WARNING
“WARNING” identifies hazards or unsafe practices that can result in serious
personal injury or death if instructions, including recommended precautions, are
not followed.
CAUTION
“CAUTION” identifies hazards or unsafe practices that can result in minor personal
injury if instructions, including recommended precautions, are not followed.
NOTICE
“NOTICE” identifies important procedures or requirements that can result in
product or property damage if instructions are not followed.
Following Safety
Instructions
If you do not understand any portion of this instruction sheet and need assistance, contact
your nearest S&C Sales Ofce or S&C Authorized Distributor. Their telephone numbers
are listed on S&C’s website sandc.com, or call the S&C Global Support and Monitoring
Center at 1-888-762-1100.
NOTICE
Read this instruction sheet thoroughly and carefully
before installing an Alduti-Rupter Switch.
Replacement
Instructions
and Labels
If additional copies of this instruction sheet are needed, contact your nearest S&C Sales
Ofce, S&C Authorized Distributor, S&C Headquarters, or S&C Electric Canada Ltd.
It is important that any missing, damaged, or faded labels on the equipment be replaced
immediately. Replacement labels are available by contacting your nearest S&C Sales
Office, S&C Authorized Distributor, S&C Headquarters, or S&C Electric Canada Ltd.

S&C Instruction Sheet 761-525 5
Safety Information
Reorder Information for Safety Labels
Location Safety Alert Message Description Part Number
ADANGER Electrocution Hazard G-6580-1
BWARNING Piercing Set Screws G-3176R1●
CWARNING Handle Operation G-4400R5
DWARNING Electrocution Hazard—Grounding Strap G-6596●
● This part is a tag to be removed and discarded after the switch is installed and adjusted.
Location of Safety Labels
C
B
D
A

6 S&C Instruction Sheet 761-525
Safety Precautions
DANGER
Alduti-Rupter Switches operate at high voltage. Failure to observe the precautions
below will result in serious personal injury or death.
Some of these precautions may differ from company operating procedures and rules. Where
a discrepancy exists, users should follow their company’s operating procedures and rules.
1. QUALIFIED PERSONS. Access to switches and
controls must be restricted only to qualified persons.
See the “Qualified Persons” section on page 2.
2. SAFETY PROCEDURES. Always follow safe operating
procedures and rules.
3. PERSONAL PROTECTIVE EQUIPMENT. Always use
suitable protective equipment, such as rubber gloves,
rubber mats, hard hats, safety glasses, and flash
clothing in accordance with safe operating procedures
and rules.
4. SAFETY LABELS AND TAGS. Do not remove or
obscure any of the “DANGER,” “WARNING,”
“CAUTION,” or “NOTICE” labels and tags. Remove tags
ONLY if instructed to do so.
5. ENERGIZED COMPONENTS. Always consider all
parts live until de-energized, tested, and grounded.
6. LOAD-INTERRUPTER SWITCH POSITION. Always
confirm the Open/Close position of load-interrupter
switches by visually observing the position of the
blades. Switches may be energized from either side and
with the blades in any position.
7. MAINTAINING PROPER CLEARANCE. Always
maintain proper clearance from energized components.
8. OPERATION. Circuit-making and circuit-breaking are
involved in the normal operation of this interrupter
switch and, as a result, “partway” opening or closing is
undesirable. To operate, swing the operating handle
through its full travel vigorously and without hesitation.
See the “Operation” section on page 26.

S&C Instruction Sheet 761-525 7
Shipping and Handling
Inspection
Examine the shipment for external evidence of damage as
soon after receipt as possible, preferably before removal
from the carrier’s conveyance. Check the bill of lading to
make sure the listed shipping skids, crates, and containers
are present:
If there is visible loss and/or damage:
1. Notify the delivering carrier immediately.
2. Ask for a carrier inspection.
3. Note the condition of shipment on all copies of the
delivery receipt.
4. File a claim with the carrier.
If concealed damage is discovered:
1. Notify the delivering carrier within 15 days of receipt of
shipment.
2. Ask for a carrier inspection.
3. File a claim with the carrier.
Also, notify S&C Electric Company in all instances of
loss and/or damage.
Packing
Study the erection drawing carefully and check the bill of
materials to be sure all parts are at hand. When a standard
mounting arrangement is specied, the shipment includes:
• Three switch poles
• Operating-pipe sections for interphase, horizontal-
connecting, and vertical sections (The switch may be
furnished “less operating pipe,” if specied.)
• Operating-mechanism components, such as handle,
rod guides, outboard bearing, and couplings—each
tagged and keyed to the bill of material for ready
identication
The components included with these modifications are
shown on the erection drawing bill of material under the
specified “-SX” suffix. They include:
-S1 One tubular fiberglass insulating section in vertical
operating shaft
-S2 One Cypoxy™ Insulator unit in vertical operating
shaft
-S6 Key interlock—single lock for a “locked-open”
application
-S6L Provision for key interlock—allows future addition
of single lock for “locked-open” application
-S7 Auxiliary contact switch with 4 N/O and 4 N/C
contacts (600 Vac, 20 A)
-S8 Provision for power operation of pole-mounted
switches by S&C Switch Operator—Type AS-10
-S9 Provision for power operation of steel-structure
or pedestal-mounted switches by S&C Switch
Operator—Type AS-10
-S16 Provision for power operation of pole-mounted
switches by S&C 6801M Automatic Switch Operator
The “-V1” or “V2” erection drawing suffix adds (one or
two, respectively) extra 6-foot 10-inch (208-cm) lengths
of pipe and includes the appropriate number of extra
couplings and guides.
Drawing RD-10009 , detailing the various modifications,
is included in addition to the erection drawing.
Power Operation: If sufx “-S8”or “-S9” is specied,
S&C Instruction Sheets 769-510 and 769-511, “Type
AS-10 Switch Operators,” are included with the switch
operator shipment. Instruction Sheets 769-510 and
769-511 cover installation, operation, and adjustment of
the appropriate switch operator and should be used in
conjunction with this instruction sheet where applicable.
If sufx “-S16” is specied, associated S&C Instruction
Sheets for the 6801M Automatic Switch Operator are
included with the switch operator shipment. Not all
mounting arrangements are suitable for power operation;
consult the nearest S&C Sales Ofce for details.

8 S&C Instruction Sheet 761-525
Shipping and Handling
Handling
The crates the switch pole-units are packed in are designed
to be moved and lifted using a lift truck. Raised slots in the
bottom of the crates are provided for a lift truck’s forks.
NOTICE
To minimize time-consuming final adjustments
after installation, make sure the switch poles are in
their fully Closed position during installation of the
interphase and vertical operating pipe sections. S&C
recommends tying the switch blades to their jaw
contacts with wire or a cable tie.
WARNING
DO NOT lift the switch pole-units by rigging on the
“live parts” or subject these parts to undue stress from
slings or fall lines.
Lifting the switch by the live parts will damage the
switch. Rough handling may cause damage to the
blades and contacts.
Failure to lift the switch properly can result in
switch damage, causing improper operation,
arcing, or electrical shock.

S&C Instruction Sheet 761-525 9
Installation
Mounting to Wood
Follow these steps when mounting to wood:
NOTICE
When mounting to a wood structure, a spring-type
washer must be used between the square washer
and the nut to maintain fastener tightness in the
event of wood shrinkage. See Figure 2.
Uncrating the Switch
STEP 1. Remove the switch poles from their crates and
arrange them on the ground in the same order in
which they will be mounted on the structure.
Protect the bearings from contamination by
dirt, mud, oil, etc. If necessary, use blocks to
keep the bearings clear of the ground.
Attaching Couplings to the Switch Poles
STEP 2. Attach the pipe couplings to the hex-crimped,
galvanized-steel pipe operating shaft of each
switch pole. Torque the clamp bolts to nal
tightness. See Figure 3.
Spring-type
washer
Figure 2. Applying the spring washer.
Pipe
coupling
Clamp bolt
Hex drive
shafts
Figure 3. Attaching the pipe couplings to the switch hex-crimped
galvanized steel pipe operating shafts.

10 S&C Instruction Sheet 761-525
Installation
Mounting the Support Members
Follow these steps when mounting support members:
STEP 3. Mount the support members (supplied by others
or ordered separately) on the structure for
the switch pole-units and the horizontal-pipe
bearing. See Figure 4.
Lifting the Switch
WARNING
DO NOT lift the switch poles by rigging to the live parts.
Avoid allowing the switch poles to swing while lifting.
Lifting the switch by the live parts will damage the
switch. Rough handling may cause damage to the
blades and contacts.
Failure to lift the switch properly can result in switch
damage, causing improper operation, arcing, or
electrical shock.
STEP 4. Hoist the switch poles using the lifting angles
provided and bolt them into position on their
supporting members as shown on the erection
drawing. See Figure 5.
Remove the lifting angles.
CAUTION
Make sure the surfaces on which the
switch pole bases are mounted are flat
and true. Mounting to an uneven surface
can cause the bases to twist, placing
undue strain on the insulators and throwing
the blades out of alignment, resulting in
difficulties operating the switch. Use shims
as required.
Figure 4. The support members.
Support members by others or
ordered separately
Figure 5. Hoisting the switch pole into position.
Lifting
angles

S&C Instruction Sheet 761-525 11
Installation
STEP 5. Mount the horizontal-pipe bearing on its sup-
port member as shown on the erection drawing.
See Figure 6.
STEP 6. To minimize time-consuming nal adjust-
ments, make sure each switch pole is fully
closed with blades against their blade stops and
the switch drive lever within -inch (2 mm) of
the closed stop-bolt. Tie the switch blades to
their stationary main contact assemblies. See
Figure 7.
Figure 6. Mounting the horizontal-pipe bearing.
Horizontal-pipe bearing
Support member
Figure 7. Tying the switch blade to the stationary main contact
assembly.
Blade
Tie
Switch drive lever
Stationary main
contact assembly
Stop-bolt
Blade stop
Tie
contact assembly

12 S&C Instruction Sheet 761-525
Installation
Installing Pipe Couplings with Piercing
Set Screws
WARNING
Failure to properly install pipe couplings with piercing
set screws can cause slippage of operating pipe,
resulting in improper operation of the switch, arcing,
equipment damage, or electrical shock.
STEP 7. To properly install piercing set screws:
(a) Make sure the cutting tip of the piercing set
screw does not protrude through the body of
the clamp.
(b) Insert the operating pipe section into the
coupling and nger-tighten the clamp bolt(s).
(c) Adjust the operating pipe to the correct
length. Then, tighten the clamp bolt(s) to
nal tightness.
(d) Tighten the piercing set screw, piercing the
pipe, and continue turning until a rm
resistance is felt.
(e) Make sure the clamp bolt(s) are tight. See
Figure 8.
Piercing set screw in shipping position (cutting tip
does not protrude through body of the clamp)
Operating pipe installed, clamp bolt fully tightened,
and piercing set screw in final position
Clamp bolt
Clamp
Coupling body
Piercing
set screw
Slug pierced
from pipe
Figure 8. Installing the pipe couplings with piercing set screws.

S&C Instruction Sheet 761-525 13
Installation
Installing the Interphase Pipe
Follow these steps when installing the interphase pipe:
STEP 8. Install the interphase and, if applicable, the
outboard pipe sections as shown on the erection
drawing. See Figure 9. Follow the directions in
the “Installing Pipe Couplings with Piercing Set
Screws” section on page 12.
Torque the clamp bolt of each pipe-coupling
clamp to final tightness, but do not tighten the
associated piercing set screw, until so directed
in Step 23 on page 21, after the mechanism has
been adjusted to attain full closure of all three
poles.
STEP 9. Attach the interphase drive lever to the
interphase (or outboard) pipe section in the
position shown on the erection drawing. See
Figure 10.
Make sure the lever is at the 45-degree
position, as indicated on the erection draw-
ing. Torque the coupling clamp bolt to final
tightness. Then, tighten the piercing set screw,
piercing the pipe, and continue until a firm
resistance is felt.
NOTICE
For the most favorable mechanical
advantage, the interphase drive lever
should be within 5 degrees of the 45-degree
position when the switch is in the Open
position as well as in the Closed position.
Figure 9. Pipe connecting switch poles.
Outboard pipe section
Interphase drive lever
Interphase pipe sections
Figure 10. Interphase drive lever installation.

14 S&C Instruction Sheet 761-525
Installation
Installing the Vertical Operating Pipe
Follow these steps when installing the vertical operating
pipe:
STEP 10. One of the pipe sections furnished is threaded at
one end to accommodate the operating handle
assembly. See Figure 11. Install this section of
pipe last, with the threads at the lower end.
If only one vertical operating-pipe section
is required, proceed to Step 13 on page 15.
STEP 11. Position and install the rod guide(s) with the
arm pointing upward on the pole or structure in
accordance with the dimension shown on the
erection drawing. See Figure 12. A positioning
stud is furnished which holds the rod guide arm
at 45 degrees.
STEP 12. Install the upper section of vertical operating
pipe between the interphase drive lever
coupling and the uppermost rod guide, with the
rod-guide arm pointing upward at a 45-degree
angle. See Figure 13. (A positioning stud is fur-
nished that holds the rod guide at 45 degrees.)
Follow the directions in the “Installing Pipe
Couplings with Piercing Set Screws” section on
page 12.
Torque the clamp bolts to final tightness.
Then, tighten the piercing set screws, pierc-
ing the pipe, and continue turning until a firm
resistance is felt.
If more than one rod guide is used, install
vertical operating-pipe sections between the
rod guides in the same manner.
Figure 11. A threaded vertical operating pipe.
Figure 12. Attaching the rod guide.
Positioning stud
Figure 13. Installing the upper operating pipe section into the
rod guide.
Positioning
stud
Uppermost
section of
vertical
operating
pipe
Clamp
bolt

S&C Instruction Sheet 761-525 15
Installation
Installing the Operating Handle●
Follow these steps when installing the operating handle:
STEP 13. Mount the operating handle assembly as shown
on the erection drawing. At the same time, use
one of the mounting bolts to attach one end of
the ground strap (the end with the grounding
connector attached) to the handle mounting
plate.■See Figure 14.
STEP 14. Install the lowest vertical operating-pipe sec-
tion by threading one end of the pipe into the
coupling on the operating handle assembly.
Approximately ¼ -inch (6 mm) of thread should
extend through the coupling. Tighten the
locknut. See Figure 15.
● If suffix “-S8” or “-S9” is specified, refer instead to S&C Instruction
Sheet 769-510, “Type AS-10 Switch Operators.” If suffix “-S16” is speci-
fied, refer instead to S&C Instruction Sheet 1045M-510, “6801M Auto-
matic Switch Operators, Reciprocating and Rotating Switch Operation:
Installation.”
■ The grounding recommendations described in this document may
differ from the standard operating and safety procedures of certain
electric utility companies. Where a discrepancy exists, the operating
procedures of the electric utility apply.
Figure 14. Mounting the operating handle.
Figure 15. Installing the lowest operating pipe section into the
operating handle assembly.
Locknut

16 S&C Instruction Sheet 761-525
Installation
STEP 15. Insert the upper end of this pipe section in the
lowest rod guide or—if only one vertical
operating-pipe section is used—the interphase
drive lever coupling and, while holding the
operating handle at a point approximately
20 degrees from the Closed position, torque the
rod guide (or interphase drive lever) coupling
clamp bolt. See Figure 16.
NOTICE
Do not tighten the piercing set screw at
the top of the lowest section of vertical
operating-pipe until satisfactory operating
handle adjustment is attained in the
“Checking Alignment” section on page 17.
STEP 16. Fasten the free end of the grounding strap to the
lowest vertical operating-pipe section a few
inches above the operating handle assembly
with the U-bolt connector provided for this
purpose. See Figure 17. Then, connect the lower
end of the strap to a suitable earth ground, using
the grounding connector provided at that end of
the strap.●
●The grounding recommendations described in this document may
differ from the standard operating and safety procedures of certain
electric utility companies. Where a discrepancy exists, the operating
procedures of the electric utility apply.
Figure 16. Installing the lowest operating pipe section into the
rod guide (or interphase drive lever) coupling.
Figure 17. Attaching the grounding strap.
Lowest section
of vertical
operating pipe
Clamp bolt

S&C Instruction Sheet 761-525 17
Installation
Checking Alignment
Follow these steps when checking alignment:
STEP 17. Remove the ties holding the switch blades to
their stationary main contact assemblies. See
Figure 18.
Remove the 45-degree positioning stud from
each rod guide. See Figure 13 on page 14.
Open and close the switch slowly to make
sure no operational difficulties are encountered
because of undetected damage in shipping.
WARNING
Open and close the switch slowly ONLY when
checking alignment or making adjustments
to the de-energized switch.
When opening or closing an energized
switch, swing the operating handle vigorously
through its full travel without hesitation.
Arcing and damage to the switch will occur
if the energized switch is operated slowly or
left in the partially Open or Closed position.
STEP 18. Move the operating handle slowly to the closed
position. See Figure 19. A denite resistance
should be felt at the end of the stroke, indicating
all slack in the operating linkage has been
taken up.
STEP 19. If there is still slack, repeat the procedure in
Step 15 on page 16 but move the operating handle
more than 20 degrees in the opening direction
before torquing the clamp bolt on the lowest rod
guide (or interphase drive lever) coupling. See
Figure 20.
Conversely, if considerable force is needed to
move the handle to the fully Closed position, or
if the handle does not swing 180 degrees to the
fully Open position, loosen the clamp bolt on
the lowest rod guide (or interphase drive lever)
coupling, and move the handle to a position less
than 20 degrees from the Closed position. Then,
torque the clamp bolt on the lowest rod guide
(or interphase drive lever) coupling. Proper
“resistance” in the operating linkage during a
closing operation is essential to ensure positive
switch closure.
If a key interlock is used (suffix “-S6”
or “-S6L”), proceed to Step 20. Otherwise,
proceed to the “Checking Operation” section on
page 19.
Figure 18. Removing the tie at the stationary main contact
assembly.
Figure 19. Verifying the slack has been taken up in the
operating linkage.
Remove tie
Figure 20. Torquing the clamp bolt at the lowest rod guide
(or interphase drive lever) coupling.
Clamp bolt

18 S&C Instruction Sheet 761-525
Installation
Installing the Key Interlock
Follow these steps when installing the key interlock:
STEP 20. The interlock group includes a Superior Type
B4003-1 Mk II single- or multiple-key interlock
(or equivalent), with zero bolt projection and
¾ -inch (19 mm) bolt travel, locking disc, and
interlockbracket.If“provisiononly”isspecied,
the interlock is not included.
Attach the key interlock to the interlock
bracket so the interlock bolt, when extended,
engages a slot in the locking disc on the operat-
ing handle. See Figure 21.
STEP 21. Block one of the two slots in the locking disc
with the blocking screw provided. (The slot to
be blocked depends on whether a locked-open
or locked-closed arrangement is required.) See
Figure 22.
NOTICE
Key interlocks are intended for proper
sequencing of switch operations; they
are not intended to provide security. The
operating handle assembly includes a
locking bar for padlocking the switch in the
Open or Closed position.
Interlock bolt
Figure 21. Attaching the key interlock to the interlock bracket.
Locking disc
Figure 22. The blocking slot in the locking disc.
Blocking
screw

S&C Instruction Sheet 761-525 19
Installation
Checking Operation
Follow these steps when checking operation:
STEP 22. Open and close the switch slowly through its
full travel.
WARNING
Open and close the switch slowly ONLY
when checking operation or making
adjustments to the de-energized switch.
When opening or closing an energized
switch, swing the operating handle vigorously
through its full travel without hesitation.
Arcing and damage to the switch will occur
if the energized switch is operated slowly or
left in the partially Open or Closed position.
Check to make sure the following conditions
exist:
(a) With the operating handle as far as it will go
in the closing direction, all main contacts of
the interrupter switch are fully closed with
the blades against their blade stops. See
Figure 23.
(b) Each switch drive lever is within -inch
(2 mm) of the closed stop-bolt. See Figure 24.
Figure 23. Checking that the blade is fully closed.
Main contacts fully closed
Blade stop
Figure 24. Verifying the switch drive lever assembly is within
 -inch (2 mm) of the closed stop-bolt.
Switch
drive lever
Stop-bolt

20 S&C Instruction Sheet 761-525
Installation
In the unlikely event that only one or two
switch poles are fully closed, loosen the
clamp bolt(s) on the interphase pipe
coupling(s) with the switch in the Closed
position. Push the switch blade(s) against
the blade stop(s), and torque the clamp bolt
of each pipe-coupling clamp to nal
tightness. Then, tighten the associated
piercing set screws, piercing the pipe, and
continue turning until a rm resistance is
felt. See Figure 25.
(c) With the operating handle as far as it will go
in the opening direction, each switch drive
lever should lie snugly against its open stop.
See Figure 26. There should be perceptible
tension in the operating pipe, locking the
switch open.
In the unlikely event these conditions are
not met, more switch blade travel is required.
Move the operating handle to its mid-
position to take the strain off the operating-pipe
linkage and loosen the two nuts that clamp the
adjustable arm of the interphase drive lever.
See Figure 27.
Shorten the adjustable lever arm one step,
or  ⅓  -inch (9 mm) and retighten the bolts.
Shortening the adjustable lever arm increases
switch-blade travel. Then, readjust for full
operating handle travel as described on page 17.
Repeat this procedure—shortening the
adjustable lever arm of the interphase drive
lever in one-step increments and readjusting
for full operating handle travel—until full
switch-blade travel is attained as described in
(a) t h roug h (c).
Blade
Pipe
couplings
Clamp bolt
Blade stop
Blade
Figure 25. Adjusting the interphase pipe.
Figure 26. Verifying the switch drive lever is against its open
stop.
Switch drive lever
Open stop
Figure 27. Shortening the adjustable lever arm of the interphase
drive lever.
Nuts (2)
Clamp bolt
Adjustable lever arm
Piercing set screw