Memorial Hermann Best Practices
July, 2013
SECTION 26 13 16 MEDIUM VOLTAGE FUSIBLE INTERRUPTER SWITCHGEAR
PART 1 - GENERAL
1.01
A.
1.02
Metal Enclosed Load Interrupter Switch, free-standing, single, duplex, selector, or lineup as
shown on the drawings.
RELATED SECTIONS
A.
Section 26 05 00: Common Work Results for Electrical
B.
Section 26 05 13: Medium Voltage Cable
C.
Section 26 05 73: Power System Studies
D.
Section 26 12 13: Liquid Filled, Medium Voltage Transformers
E.
Section 26 12 16: Dry Type, Medium Voltage Transformers
F.
Section 26 13 19: Medium Voltage Vacuum Interrupter Switchgear
1.03
.
WORK INCLUDED
REFERENCES
A.
ANSI/IEEE C37.20.2 - Standard for Metalclad and Station Type Cubicle Switchgear
B.
ANSI/IEEE C37.20.3 - Standard for Metal Enclosed Interrupter Switchgear
C.
ANSI/IEEE C37.20.4 - Standard for Indoor AC Switches for Use in Metal Enclosed Switchgear
D.
ANSI/IEEE C37.22 - Preferred Ratings for Indoor Medium Voltage Switches Used in Metal
Enclosed Switchgear
E.
ANSI/IEEE C37.57 - Metal Enclosed Interrupter Switchgear Assemblies - Conformance Testing
F.
ANSI/IEEE C37.58 - Conformance Test procedures for Indoor AC Medium Voltage Switches for
Use in Metal Enclosed Switchgear
G.
ANSI/IEEE 48 - Standard Test Procedures and Requirements for High-Voltage AlternatingCurrent Cable Terminations
H.
ANSI Z55.1 - Gray Finishes for Industrial Apparatus and Equipment
I.
ANSI C1 / NFPA 70 - National Electrical Code
J.
ANSI C2 - National Electrical Safety Code
K.
ANSI / NECA 1 - Practices for Good Workmanship in Electrical Construction
L.
NEMA SG5 - Power Switchgear Assemblies
M.
NEMA SG6 - Power Switching Equipment
MEDIUM VOLTAGE FUSIBLE INTERRUPTER SWITCHGEAR
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Memorial Hermann Best Practices
July, 2013
1.04
A.
Provide a minimum of 8 copies of the following documents, where applicable, to Owner for review
and evaluation in accordance with general requirements of Division 01 and Division 26:
1.
Front view and floor plan of switchgear
2.
Switchgear anchoring locations
3.
Conduit and busway entry / exit locations
4.
Location of shipping splits
5.
One-line and three-line diagrams of switchgear bus and protective devices
6.
Switchgear ratings including:
a.
Short circuit rating
b.
System voltage rating
c.
Continuous current rating
7.
Protective device schedule including:
a.
Device type
b.
Sensor and trip rating
c.
Location within the switchgear
d.
Cable quantity and size capabilities for each device
8.
Panel drawing showing all major protection, instrumentation, and control devices
mounted within the switchgear
9.
Schematic diagram showing power, metering, and control circuits for the switchgear and
circuit breakers
10.
Bill of Material listing (including quantity, location, catalog number, and ratings) of all
major protection, instrumentation and control devices
11.
Switchgear nameplate schedule
B.
Submit product data (8 copies)
C.
Submit manufacturer's installation instructions. (8 copies)
1.05
A.
1.06
PROJECT RECORD DOCUMENTS
Submit a minimum 8 copies of record information including:
1.
As-built record drawings as follows:
a.
Front View
b.
Floor Plan
c.
Elementary Diagram showing power, metering and control circuits
d.
Switchgear internal wiring diagrams
e.
Bill of Material
f.
One Line Diagram
g.
Three Line Diagram
2.
Instruction books on major components
3.
Installation drawings
4.
Certified test reports
5.
Recommended renewal parts information
OPERATION AND MAINTENANCE DATA
A.
Provide minimum 8 copies of installation, operation and maintenance procedures to owner in
accordance with general requirements of Division 01 and Division 26.
B.
Submit operation and maintenance data based on factory and field testing, operation and
maintenance of specified product.
1.07
.
SUBMITTALS
QUALITY ASSURANCE
MEDIUM VOLTAGE FUSIBLE INTERRUPTER SWITCHGEAR
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Memorial Hermann Best Practices
July, 2013
A.
Manufacturer: Company specializing in medium voltage load interrupter switchgear with at least
five years documented experience.
B.
Provide listing by Underwriters Laboratories for 5KV or 15KV class medium voltage load
interrupter switchgear.
1.08
DELIVERY, STORAGE, AND HANDLING
A.
Switchgear shall be provided with adequate lifting means and shall be able to be rolled or moved
into installation position and bolted directly to floor without using floor sills.
B.
Deliver, store. Protect, and handle products in accordance with recommended practices listed in
manufacturer's Installation and Maintenance Manuals.
C.
Deliver each switchgear lineup in shipping sections for ease of handling. Each section shall be
mounted on shipping skids.
D.
Inspect and report concealed damage to carrier within specified time.
E.
Store in a clean, dry space. Maintain factory protection or cover with heavy-duty plastic, minimum
6 mil, to keep out dirt, water, construction debris, and traffic. Heat enclosures to prevent
condensation.
F.
Handle switchgear in accordance with manufacturer's written instructions to avoid damaging
equipment, installed devices, and finish. Lift only by installed lifting provisions.
1.09
PROJECT CONDITIONS (SITE ENVIRONMENTAL CONDITIONS)
A.
Follow applicable NEMA, ANSI, and NECA standard practices before, during, and after
switchgear installation.
B.
Switchgear shall be located in well-ventilated areas, free from excess humidity, dust, and dirt and
away from hazardous materials. Ambient temperature of area will be between minus [30] and
plus [40] degrees C. Indoor locations shall be protected to prevent moisture from entering
enclosure.
1.10
A.
1.11
A.
1.12
SEQUENCING AND SCHEDULING
Provide a written detailed description of scheduled installation, testing, and startup dates.
WARRANTY
Manufacturer warrants equipment to be free from defects in materials and workmanship for
greater of 1 year from date of installation or 18 months from date of delivery.
EXTRA MATERIALS/ACCESSORIES
A.
Provide a list of recommended maintenance materials.
B.
Provide one set of spare fuses for each type and size of fuse installed. Provide an adequately
sized storage cabinet with hinged door to house the spare fuses.
PART 2 - PRODUCTS
2.01
A.
.
MANUFACTURERS
Eaton/Cutler-Hammer
MEDIUM VOLTAGE FUSIBLE INTERRUPTER SWITCHGEAR
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Memorial Hermann Best Practices
July, 2013
B.
Square D
C.
Siemens
D.
Products of manufacturers not listed as approved will be considered for approval if technical data
is submitted at least two weeks before bid date. Substitutions will not be considered after this
period.
2.02
A.
PRIMARY INCOMING LINE SECTION - The load interrupter switch shall have an incoming
terminal compartment with NEMA drilled pads. Refer to the drawings for specific wire size and
type. The terminal compartment may be part of the switch structure unless shown otherwise. The
terminals shall be radial feed, unless otherwise indicated.
B.
Provide a set of intermediate class surge arresters mounted inside the terminal section and
grounded to the metal structure. Arrestors KV rating shall match the equipment ratings shown on
the drawings. Arrestors shall be equal to GE TRANQUELL(r).
C.
When part of a unit substation, the load interrupter switch is close-coupled to transformer as
shown on the drawings. Provide kirk-key interlocking transformer secondary main circuit breaker
such that fuse compartment cannot be opened unless secondary breaker is open and interupter
switch is open. Switch finish shall match transformer finish.
D.
Non-Loadbreak Selector Switches
1.
For 5 or 15kV ratings, furnish a two-position non-loadbreak selector switch for the
selection of two incoming sources in series with the load break MVS switch where shown
on contract drawing. The selector switch shall have the same continuous current rating
as the load interrupter switch in the same structure. Interlocking shall be supplied so that
the selector switch can only be operated with the load interrupter switch in the open
position. Also, neither the main door nor the load interrupter switch shall be able to be
closed without the selector switch being positively locked in one of the two source
positions.
E.
Duplex Switchgear Assembly
1.
Furnish, where shown on the drawings, a duplex switchgear assembly configuration
consisting of two (2) load interrupter switches with common load side bus to feed one
load circuit, which shall be fused. Key interlocks shall be supplied to prevent opening the
front door of each vertical section containing one of the two switches unless both
switches are locked open.
2.03
A.
2.04
A.
.
EQUIPMENT
RATINGS
Ratings - The load interrupter switch ratings shall be as follows:
1.
Nominal System Voltage and Bus Current rating shall be 15 kV, 1200 ampers, unless
otherwise indicated on the drawings.
2.
System Type: - solidly grounded wye
3.
Basic Impulse Level (BIL) - 5kV - 60 BIL or 15kV - 95 BIL.
4.
Momentary Current - 40kA asymmetrical for 5kV and 15kV
5.
Fault Close Current - 40kA asymmetrical for 5kV and 15 kV
CONSTRUCTION
The load interrupter switch assembly shall be metal enclosed front accessible or rear accessible},
full height, self-supporting sections constructed of ANSI/IEEE C37.20.3 sheet steel doors,
barriers, and side covers, and bolted frame. Each section shall be adequately braced and shall
MEDIUM VOLTAGE FUSIBLE INTERRUPTER SWITCHGEAR
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Memorial Hermann Best Practices
July, 2013
have adequate ventilation to prevent distortion of the cubicle doors and windows under operating
conditions.
B.
The load interrupter switch shall be fused. The switch shall be two position, 3-pole, gang operated
with a stored energy quick make/quick break mechanism that opens and closes the switch
regardless of speed at which the operating handle is moved. Switch shall be operated from the
front of the cubicle by means of a non-removable operating handle.
C.
Provide non-metallic phase barriers form the full length of the switch blade and fuse for each
pole.
D.
The double air-interrupter switch shall be rated as 15 kV, 1200 ampers unless otherwise indicated
in the drawings. It shall consist of two 2-position (open, close), 3-pole, gang-operated, air
interrupter switches, equipped with stored-energy mechanisms. Switches shall be key interlocked
so that both switches must be open to access the fuses.
E.
Where used on a unit substation with an alternate source of power to the secondary bus, the
switch shall be key interlocked with the secondary main such that the main must be open to
access fuses.
2.05
A.
One set of three (3) current limiting power fuses {{GE Type EJO}} shall be mounted in separate
compartment within each switch unit.
B.
Fuses shall be accessible through a hinged door mechanically interlocked with interrupter switch
such that entry may be accomplished by de-energizing the switch. On switch feeding unit
substations that have a possible 2nd source of power, a warning sign shall be placed on the door
indicating that fuses may be energized when switch is open. Fuses shall be rated as indicated on
the drawings and suitable for use on circuit having short-circuit capacity of 250, 500 or 750 MVA
symmetrical at 5kV or 15kV.
C.
Fuses shall be accessible through a hinged door mechanically interlocked with interrupter switch
such that entry may only be accomplished by de-energizing the switch. Current rating of fuses as
indicated on drawings and shall be suitable for use on circuit having short-circuited capacity as
noted on the drawings.
D.
Fuses shall be held in position with provision for removal and replacement from the front without
the use of special tools.
2.06
.
FUSES
MAIN BUS
A.
All phase bus conductors shall be tin-plated copper and be mounted on NEMA rated
cyclophenolic epoxy insulators. Bus connections shall be bolted with a minimum of 2 bolts. The
bus shall be braced to withstand the effects of a short circuit within the ratings of the equipment.
All bus shall be insulated with sleeve type insulation. Where joints are made, the joints shall be
covered with molded covers.
B.
The full-length ground bus conductor shall be copper directly fastened at the front of each vertical
section. A 4/0 AWG two hole, long barrel compression lug shall be provided at each end of the
ground bus. Ground bus shall be sized such that a line-to-ground or double line-to-ground fault
current of 125% of 3 phase fault current rating shall be cleared by maximum size fuse possible
without damage to the bus or supports.
C.
Provide glass polyester standoff insulators on switches and fuse mountings
D.
Provide removable insulated boots for all terminations.
MEDIUM VOLTAGE FUSIBLE INTERRUPTER SWITCHGEAR
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Memorial Hermann Best Practices
July, 2013
2.07
A.
The switch shall be NEMA 1 for indoor use., NEMA 2, drip proof for indoor use or NEMA 3R for
outdoor use.
B.
Provide each vertical section with a sloped weatherproof roof with labyrinth shaped joints. All
exterior openings shall be screened with rodent barriers. Provide a minimum of (1) 250 watt, 120
volt space heater in each vertical section each thermostatically controlled. Provide ventilated
openings to allow airflow in each vertical section. The ventilated covers shall be externally
removable for safe access to the filter media.
C.
A large shatter-resistant inspection window made of Lexan shall be provided in the door of each
switch section to allow operator viewing of the switch blade position without opening the door.
D.
Individual doors shall be provided for the switch and fuse compartments. A mechanical interlock
shall be provided to prevent access to the live side of the switch when the switch is in the "on"
position or the fuse compartment door is open. Additionally, a horizontal safety barrier between
the two compartments shall be provided. All steel doors shall have concealed hinges and captive
hardware to secure the door in the closed position.
E.
Provisions for padlocking the load interrupter switch in either the open or close position shall be
provided.
F.
The structure shall be provided with a removable lifting means and be suitable for jacking or
rolling into position.
G.
Permanent non-corrosive nameplate. All units shall have the appropriate hazardous danger
signs prominently displayed on the exterior and interior of each section.
H.
Louvered, penetration resistant, vents on indoor units. Louvered, penetration resistant, vents with
removable filters on outdoor units. Walk-in enclosure shall have power exhaust fans sized for a
minimum of 4 air changes per hour.
I.
Provide relays, meters, control switches as required, mounted on a front hinged panel. To the
extent possible while meeting the requirements of the specifications, , relays shall be provided by
the same manufacturer for all power distribution equipment provided for this project. Meters shall
be provided by the same manufacturer for all power distribution equipment provided for this
project.
2.08
A.
2.09
.
ENCLOSURE
FINISH
All enclosure surfaces shall be thoroughly cleaned of scale, oil, grease, rust and other foreign
matter prior to painting and then treated with phosphoric acid, etched, and cleaned. An
electrostatic powder 2-5 mill thick coating shall be applied and oven cured. Finish shall be ANSI
61 light Gray. Paint finish shall be rated for 1,000 hours salt spray per ANSI C37.20.3.
CIRCUIT MONITOR
A.
Where electronic power monitor is indicated on the drawings, provide a Cutler-Hammer IQ
Analyzer 6600, GE KVC2, or approved equal meter, mounted as required. Refer to Section 26
09 15, Electronic Power Monitor, for acceptable manufacturers.
B.
Provide a customer metering compartment with front hinged doors. Provide multi-function
electronic relays unless otherwise indicated on the drawings.
C.
Electronic power monitor shall be as specified in section 26 09 13.
MEDIUM VOLTAGE FUSIBLE INTERRUPTER SWITCHGEAR
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Memorial Hermann Best Practices
July, 2013
2.10
A.
One (1) terminal pad per phase shall be provided for attaching contractor-supplied cable terminal
lugs for a maximum of two (2) conductors per phase of the sizes indicated on the drawings.
Sufficient space shall be allowed for contractor supplied electrical stress relief termination
devices.
B.
Small wiring, fuse blocks and terminal blocks within the vertical section shall be furnished as
indicated on the drawings. Each control wire shall be labeled with wire markers. Terminal blocks
shall be provided for owner's connections to other apparatus.
C.
The switchgear shall be wired with type SIS #14 AWG, stranded, except where larger size wire is
specified. CT circuits shall be #10 AWG. The switchgear shall be provided with terminal blocks for
outgoing control connections. Wire markers shall be provided for each end of all control wires.
D.
Current transformer wiring shall use shorting type terminal blocks.
E.
Protective Relays: Provide instruments as indicated on drawings for each switch.
2.11
A.
2.12
A.
2.13
.
WIRING/TERMINATIONS
INSTRUMENT TRANSFORMERS
Current Transformers: The current transformer assembly shall be insulated for the full voltage
rating of the switchgear. Relaying and metering accuracy shall conform to ANSI Standards.
Voltage transformers are fixed mounted with primary current-limiting fuses and shall have ratio as
required to deliver secondary voltage of 120V at rated bus voltage. The transformers shall have
mechanical rating equal to the momentary rating of the switch and shall have metering accuracy
per ANSI Standards. High accuracy and/or ratios below 300:5 - two per phase.
ACCESSORIES AND ADDITIONAL FEATURES
Each load interrupter switch shall include:
1.
Dust resistance enclosure
2.
UL labeled as service entrance switchgear
3.
Plastic Mimic bus
4.
Weather resistance enclosure
5.
Rear doors. (identical to front)
6.
Vertical barriers
7.
Auxiliary switches, 2-NO 2-NC
8.
Space heaters with thermostat
9.
Operations counter
10.
Bottom closure plates
11.
Rodent barriers
12.
Tamper resistant hardware
13.
Porcelain insulators
14.
Provide a control power transformer to power space heaters on outdoor enclosure
15.
Provide metering as indicated on drawings
16.
Provide motor operators for the switch(es) as indicated on the drawings
17.
Provide motor operators and an automatic transfer scheme as indicated on the drawings
18.
Louvered, penetration resistant, vents with removable filters on indoor units
19.
The neutral bus, where required, shall be full size and installed on 600 volt insulators
20.
Provide infrared scanning ports
21.
The load interrupter switch shall be installed in a metal clad switchgear assembly. See
section 26 13 19 for assembly details and requirements.
TESTING
MEDIUM VOLTAGE FUSIBLE INTERRUPTER SWITCHGEAR
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Memorial Hermann Best Practices
July, 2013
A.
Each load interrupter switch shall receive all routine commercial tests in accordance with
applicable ANSI standard.
B.
Manufacturer shall provide 10 certified copies of factory test reports.
PART 3 - EXECUTION
3.01
EXAMINATION
A.
Visually inspect switchgear for evidence of damage and verify that surfaces are ready to receive
work.
B.
Visually inspect to confirm that all items and accessories are in accordance with specifications
and drawings.
C.
Verify field measurements are as shown on drawings and as instructed by manufacturer.
D.
Verify that required utilities (e.g., control voltage for heater circuits on outdoor switchgear) are
available, in proper location, and ready for use.
E.
Beginning of installation means installer accepts existing surface conditions.
3.02
INSTALLATION
A.
Install in accordance with manufacturer's instructions, applicable requirements of the National
Electrical Code, National Electrical Safety Code, ANSI/NECA 1, and in accordance with
recognized industry practices.
B.
Use jumper cables, as provided by the switchgear manufacturer, to connect the primary surge
arresters.
C.
Bending of high-voltage cables should be avoided or minimized. All necessary bends should
meet at least the minimum radii specified by the cable manufacturer.
3.03
FIELD QUALITY CONTROL
A.
Visually inspect for physical damage.
B.
Perform mechanical operator tests in accordance with manufacturer's instructions.
C.
Check torque of all bolted bus connections, including cable terminations.
D.
Touch-up paint all chips and scratches with manufacturer-supplied paint and leave remaining
paint with owner.
E.
Verify key interlock operation.
F.
Perform insulation resistance tests per manufacturer's published instructions.
G.
Perform low frequency withstand tests according to ANSI/IEEE C37.20.2, paragraph 5.5.
H.
Provide field service, start-up, and training for load interrupter switchgear.
END OF SECTION
.
MEDIUM VOLTAGE FUSIBLE INTERRUPTER SWITCHGEAR
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