S&C VacuFuse II User guide

Instruction Sheet 466-501
December 19, 2022
© S&C Electric Company 2022, all rights reserved
VacuFuse®II Self-Resetting Interrupter—Quick Operation Guide
Outdoor Distribution (12.47 kV through 27.0 kV)
Understanding the LED Indicators and POSITION Indicator
LED Indicators
There are two LEDs on the base of the VacuFuse II interrupter. See Figure 2.
The CHARGING LED is white and indicates the VacuFuse II interrupter is harvesting
energy to close the vacuum interrupter. When the VacuFuse II interrupter is powered, the
CHARGING LED will start flashing at one flash per second as long as sufficient voltage
is present in the cutout mounting and the vacuum interrupter is open. When full charge
is achieved, the READY TO CLOSE LED will illuminate and the CHARGING LED will
continue blinking.
POSITION Indicator
The POSITION indicator is located on the base of the VacuFuse II interrupter’s housing.
It contains a highly reective visible red or green target that indicates the position of
the vacuum interrupter inside the device. The target is green when the vacuum
interrupter is in the Open position and red when the vacuum interrupter is in the
Closed position, unless the VacuFuse II interrupter was ordered with the “-J1” sufx
(red open/green closed).
Installing a VacuFuse II Interrupter into the Cutout Mounting
WARNING
Provide training to line crews on the use of both a hotstick and an extendostick
before installing or operating the VacuFuse II Self-Resetting Interrupter. The
VacuFuse II interrupter is different from other cutout-mounted devices. Failure to
properly handle a VacuFuse II interrupter with a hotstick and/or an extendostick
may lead to serious injury or death.
For instructions on how to install a cutout mounting, see the “Installing the VacuFuse II
Self-Resetting Interrupter Mounting” section of S&C Instruction Sheet 466-500.
WARNING
VacuFuse II Self-Resetting Interrupters must be installed, operated, and maintained
by qualified persons knowledgeable in overhead electric power distribution equipment
and the associated hazards. This guide is not a replacement for adequate training
and experience in safety procedures for this product. Read S&C Instruction Sheet
466-500 thoroughly and carefully before installing or operating your VacuFuse II
Self-Resetting Interrupter.
DANGER
VacuFuse II Self-Resetting Interrupters may be energized from either side and in any
position. Always consider all parts live until de-energized, tested, and grounded.
Understanding the Closing Sequence
Note: The VacuFuse II Self-Resetting Interrupter is shipped from the factory with the
vacuum interrupter in the Open position.
When closing the VacuFuse II Self-Resetting Interrupter into the cutout mounting
the CHARGING LED will blink at a one-second interval as long as there is sufficient
voltage present in the cutout mounting and the vacuum interrupter is open. The READY
TO CLOSE LED will steadily illuminate when the VacuFuse II interrupter has harvested
enough energy to close the vacuum interrupter and when the manual operating lever is
in the Down position.
The VacuFuse II Self-Resetting Interrupter requires 45 ±10 seconds to harvest enough
energy to close the vacuum interrupter.
There are two ways to close the vacuum interrupter:
Option 1: Automatic Delayed Close
Place the manual operating lever into the Up position at any time prior to closing the unit
into the cutout mounting, or less than 35 seconds after the CHARGING LED has begun
blinking. When closed into the cutout mounting in this state, the CHARGING LED will
blink at a one-second interval if there is sufcient voltage present in the cutout mounting
and the vacuum interrupter is open. The VacuFuse II interrupter will automatically close
the vacuum interrupter after 45 ±10 seconds.
Option 2: Manual Close
Place the manual operating lever into the Down position prior to closing the unit into the
cutout mounting or less than 35 seconds after the CHARGING LED has begun blinking.
Wait until the READY TO CLOSE LED illuminates and is solidly lit. At that time, the
interrupter is ready to be closed manually by moving the manual operating lever to
the Up position. Three seconds after the lever is moved to the Up position, the vacuum
interrupter will close.
Always check the position of the vacuum interrupter by confirming the POSITION
indicator at the base of the interrupter is red before walking away. See Figure 1.
Figure 1. A VacuFuse II Self-Resetting
Interrupter (vacuum interrupter closed).
POSITION
indicator
LED
indicators
Figure 2. A VacuFuse II Self-Resetting
Interrupter (vacuum interrupter open).
CHARGING
LED
POSITION
indicator in
the Open
(green)
position
READY TO
CLOSE LED
STEP 1. If using an existing cutout mounting: Visually inspect the cutout mounting
for damage or excessive wear, particularly in the upper and lower contact
areas. If ANY damage is visible, replace the cutout mounting before proceeding.
DO NOT install and/or energize a VacuFuse II interrupter into a damaged
cutout mounting.
STEP 2. Installation using insulated gloves: With the manual operating lever in the
Up position, insert the VacuFuse II interrupter into the proper cutout mounting
with gloved hands, as shown in Figure 5 on page 2.
Installation using the Talon™ Handling Tool: Attach a Talon Handling
Tool to a short hotstick. Insert the curled prong of the Talon tool into the lifting
eye of the trunnion, and raise the VacuFuse II interrupter into the mounting.
Rotate the hotstick counterclockwise 180 degrees to disengage it.
Closing the VacuFuse II Interrupter into the Cutout Mounting
NOTICE
Read the “Understanding the Closing Sequence” section before closing the
VacuFuse II interrupter into its cutout mounting.
STEP 1. Conrm the VacuFuse II interrupter is in the Open position by viewing its
POSITION indicator. Place the manual operating lever in the correct position
for the closing sequence desired.
STEP 2. Stand rmly in front of and in line with the cutout mounting. Do not operate
standing directly underneath the VacuFuse II interrupter. If using an
extendostick, stand from 6 to 10 feet (1.8 to 3.1 m) away from the pole.
STEP 3. Insert the straight prong of a Talon tool or distribution prong into the pull-ring.
STEP 4. Swing the VacuFuse II interrupter to within approximately 45 degrees of the
fully Closed position. See Figure 3.
STEP 5. While rmly gripping the stick, drive the VacuFuse II interrupter closed with
forward force. Maintain the forward force until the interrupter properly closes
and latches into the cutout mounting.
STEP 6. Disengage the prong from the pull-ring, taking care to avoid pulling the
VacuFuse II interrupter open.
Figure 3. A VacuFuse II interrupter within
approximately 45 degrees of the fully
Closed position.
45°

2 S&C Instruction Sheet 466-501
VacuFuse®II Self-Resetting Interrupter—Quick Operation Guide
Outdoor Distribution (12.47 kV through 27.0 kV)
STEP 2. Wait about one minute 45 seconds until the VacuFuse II interrupter drops out.
If the VacuFuse II Self-Resetting Interrupter stays in its cutout mounting, confirm the
POSITION indicator at the base of the VacuFuse II interrupter displays a green target.
In this case, the VacuFuse II interrupter may not be powered and cannot drop out. Refer
to the “Troubleshooting” section of S&C Instruction Sheet 466-500 to determine the
appropriate action to take.
If the VacuFuse II Self-Resetting Interrupter is in its cutout mounting with the
vacuum interrupter in the Closed position and operating the manual operating lever
to the Open position does not work, or the VacuFuse II interrupter is to be removed
from its cutout mounting in the Closed position for any other reason, follow the instruc-
tions in the “Removing the VacuFuse II Interrupter from the Cutout Mounting using
Loadbuster®—The S&C Loadbreak Tool” section of S&C Instruction Sheet 466-500.
WARNING
DO NOT attempt to open a VacuFuse II Self-Resetting Interrupter that is in the
Closed position without using a loadbreak tool, such as S&C’s Loadbuster tool. An
arc started by opening a VacuFuse II Self-Resetting Interrupter under load without
a loadbreak tool can cause equipment damage, serious injury, or death.
Instructions for using S&C’s Loadbuster tool can be found in S&C Instruction Sheet
466-500.
STEP 3. Removal using gloved hands: Remove the VacuFuse II interrupter from its
mounting with gloved hands, as shown in Figure 5.
STEP 4. Removal using the Talon Handling Tool: Attach a Talon tool to a short
hotstick. Insert the curled prong of the Talon tool into the lifting eye of the
trunnion, and raise the VacuFuse II interrupter out of its mounting.
If the VacuFuse II Self-Resetting Interrupter Is Found Open
WARNING
The VacuFuse II Self-Resetting Interrupter is designed to protect distribution
transformers from internal and external fault current. A VacuFuse II interrupter found
in the Open and Drop Out position should not be closed using the manual operating
lever until the cause of the fault current has been determined and repaired. Closing
without repairing the fault could result in equipment damage, injury, or death.
WARNING
VacuFuse II Self-Resetting Interrupters must be dropped out from the cutout mounting
to be considered open.
VacuFuse II Self-Resetting Interrupters are different from other cutout-mounted
devices, including the VacuFuse® Self-Resetting Interrupter. VacuFuse II interrupters
have a voltage-harvesting power supply that allows up to 1 mA of current to go through
them, even when the vacuum interrupter is open.
Failure to consider the current through the VacuFuse II interrupter when the vacuum
interrupter is open may lead to serious injury or death.
After responding to an overcurrent event, the VacuFuse II interrupter’s vacuum inter-
rupter will open and the POSITION indicator will show a green target. If the overcurrent
event persists after the reclosing event, the interrupter will lock out and drop out from
the cutout mounting. Note that non-reclosing VacuFuse II interrupters will lock out and
drop out from the cutout mounting every time the device responds to an overcurrent
event. Follow these steps if the VacuFuse II Self-Resetting Interrupter has operated and
is in the Open and Drop Out position:
STEP 1. Remove the VacuFuse II interrupter from its mounting, if required by utility
practice, following the steps in the “Removing the VacuFuse II Interrupter from
the Cutout Mounting” section.
STEP 2. Determine and resolve the cause of the fault. After the fault has been resolved
and repairs completed, install the VacuFuse II interrupter and close it into the
mounting as described in the “Installing a VacuFuse II Interrupter into the
Cutout Mounting” section.
If Maintenance Is to Be Performed on the Transformer
STEP 1. Open the vacuum interrupter inside the VacuFuse II interrupter by moving the
manual operating lever to the Down position using the straight prong of the
Talon Handling Tool or a distribution prong. See Figure 4.
STEP 2. After the VacuFuse II Self-Resetting Interrupter opens and drops out (after
approximately 1 minute and 45 seconds), remove the unit from its mounting, if
required by utility practice. Follow the steps in the “Removing the VacuFuse II
Interrupter from the Cutout Mounting” section. This creates a visible open gap
showing the transformer is isolated from the feeder. Depending on utility
practice, additional grounds may be required.
STEP 3. Follow your utility’s standard practice for transformer maintenance. After
maintenance is complete, install the VacuFuse II interrupter and close it into
the mounting as described in the “Installing a VacuFuse II Interrupter into the
Cutout Mounting” section.
Opening and Closing the VacuFuse II Interrupter
WARNING
The VacuFuse II Self-Resetting Interrupter is designed to protect distribution
transformers from internal and external fault current. A VacuFuse II interrupter found
in the Open and Drop Out position (POSITION indicator displaying a green target)
should NOT be closed until the cause of the fault current has been determined and
repaired. Closing without repairing the fault could result in equipment damage, injury,
or death.
The vacuum interrupter inside the VacuFuse II interrupter can be opened using the yellow
manual operating lever on the side of the VacuFuse II interrupter, with or without power.
The interrupter must be closed in the cutout mounting with sufcient voltage present
for at least 45 seconds before the vacuum interrupter can be closed by moving the lever
to the Up position.
The VacuFuse II Self-Resetting Interrupter will drop out of the cutout mounting after
one minute when the vacuum interrupter is in the Open position and the READY TO
CLOSE LED is lit.
To open: Pull the yellow manual operating lever down rmly using the straight prong of
the Talon tool or a distribution prong. Remove the tool right away. The vacuum interrupter
inside the VacuFuse II interrupter will open, and the POSITION indicator will show the
green target. See Figure 2 on page 1. After one minute and 45 seconds of the vacuum
interrupter in the Open position, the VacuFuse II interrupter will drop out.
To close: Push the pull-ring of the manual operating lever up rmly using the straight
prong of the Talon tool or a distribution prong. The vacuum interrupter inside the
VacuFuse II interrupter will close after 45 seconds of sufcient voltage present at the
cutout mounting, and the POSITION indicator will show the red target. See Figure 2.
If the VacuFuse II interrupter is inadvertently closed into a fault, the vacuum interrupter
will trip open independently of any force still applied to the manual operating lever.
To reset the manual operating lever after manually closing into fault current:
When the VacuFuse II interrupter trips in response to a fault, the lever does not move,
leaving the lever in the Up position when the vacuum interrupter is in the Open position.
The lever can be “reset” by operating it into the Down position while the vacuum
interrupter is in the Open position.
Removing the VacuFuse II Interrupter from the Cutout Mounting
WARNING
DO NOT attempt to remove a VacuFuse II interrupter from its cutout mounting
with the vacuum interrupter in the Closed position. The vacuum interrupter is in
the Closed position when the POSITION indicator at the base of the VacuFuse
II interrupter displays a red target. Removing the VacuFuse II interrupter from its
cutout mounting with the vacuum interrupter in the Closed position may cause
arcing, equipment damage, serious injury, or death.
STEP 1. Open the vacuum interrupter by pulling down on the yellow manual operating
lever. Conrm the POSITION indicator at the base of the VacuFuse II
interrupter displays a green target. See Figure 2 on page 1.
Figure 4. A VacuFuse II Self-Resetting
Interrupter.
Manual
operating
lever
Hinge-end
contact
Jaw-end
contact
Pull-ring
Trunnion
Figure 5. Guiding or removing the trunnion
from the hinge using gloved hands.
Trunnion