Siemens Medium-Voltage Gas-Insulated Switchgear Technical Overview

Medium-Voltage, Gas-Insulated
Arc-Resistant Switchgear
Types 8DA10 & 8DB10

Siemens medium-voltage gas-insulated arc-resistant switchgearis:
Increased safety1
Improved reliability2
3 Increased flexibility
4 Innovative features
5 Easy to use
Cost effective6 Type 8DA10 gas-insulated arc-resistantswitchgear
Power Distribution
Medium-Voltage Gas-Insulated Switchgear
Page 2

• Non toxic
• No hazardous substance 1)
• Colorless, odorless and chemical neutral(inert)
• Heavier then air
• ... with compact design
• ... with high personnel safety
• ... with minimized fire load
• ... with high operational availability & reliability
Until today no climate-neutral gas is known with comparablecharacteristics
Core Technology: Insulating Medium SF6
SF6 technology enableselectrical
equipment ...
Page 3

• Vacuum interrupter technology
• Ratings:
• Maximum voltage: 4.76 kV, 15 kV, 27 kV or 38 kV
• Continuous section current: up to 2,500 A
(or 4,000 A using parallel circuitbreakers)
• Short-circuit current: up to 40 kA
• Lightning-impulse withstand (BIL): up to 200 kV
• Tested to ANSI/IEEE C37.20.7-2007/
IEC 62271-200 arc-resistant internal arc
classification type 2B (front, side, rear with low-
voltage compartment door open)
• Low-pressure SF6 gas used as an insulating
medium for all primary components
• Primary components virtually maintenance-free
due to controlled gas environment
Page 4
Features & Benefits

© Siemens Industry, Inc. 2016.
• Circuit breaker endurance:
• Mechanical endurance: 10,000 times
• Mechanical endurance (optional): 30,000 times
• Electrical endurance : 10,000 times
• Full-fault switching capability: 50 times
• Compact footprint per section:
• 24” W x 64” D (8DA10 single bus)
• 24” W x 105” D (8DB10 double bus)
• Integral isolation by use of a three-position
selector switch (CONNECTED, DISCONNECT &
GROUND positions)
• Fixed-mounted circuit breakers (no special tools
for racking or lift truck for handling)
• Over 94,000 sections installed worldwide with
more than 4,500 installed in the U.S
Features & Benefits
Page 5

8DA10 Single Busbar Lineup Up To 42 kV
Page 6
Front
view
Available at Koontz Wagner,
6510- Bourgeois Houston, TX 77066

8DA10 single bus bar 8DB10 double bus bar
Types 8DA10 & 8DB10
Isolated-phase design eliminates possibility of phase-to-phase faults inside the switchgear
Page 7

Compartmentalization
Single-busbar switchgear
Arrangement of gas-filled compartments
1 2 3 Item Description
1, 2, 3
Gas zone, one each for
main bus phase 1, phase
2 & phase 3
4
Gas zone, common for
circuit breaker phase 1, 2
& 3 associated feeder
connections
5
Gas zone, common for
bus sectionalizer bus for
phases 1, 2 & 3
1 2 3
5
4
Page 8
1 2 3

Item Unit
Single-busbar (8DA10)
& double-busbar
(8DB10) switchgear
Single- pole
(8DA11) & double-
pole (8DA12)
traction power
supply switchgear*
Rated maximum design voltage kV 15 27 38** 17.5 27.5
Rated frequency Hz 50/60 50/60 50/60 16.7 50/60
Rated short-duration power-frequency
withstand voltage
kV 36 50 80 50 95
Rated lightning-impulse withstand voltage kV 95 125 200 125 200
Rated peak-withstand current kA 104 104 104 82 104
Rated short-circuit making current (peak) kA 104 104 104 82 104
Rated short-circuit withstand current 3 s kA 40 40 40 31.5 40
Rated short-circuit breaker current kA 40 40 40 31.5 40
Rated normal current of busbar, maximum A 5,000 5,000 5,000 2,500 3,150
Rated normal current of feeders, maximum A 2,500 2,500 2,500 2,000 2,500
Technical Data
* Consult Siemens Smart Grid division, Rail Electrification business, for information on traction power supply switchgear.
http://w3.usa.siemens.com/smartgrid/us/en/rail-electrification/Pages/Rail-Electrification.aspx
** Consult Siemens for rated maximum design voltage up to 42 kV.
Page 9

Footprint comparison (MV AIS & MV GIS - only equipment size considered)
38 kV
15 kV
MV
AIS
MV
GIS
MV
GIS
MV
AIS
~75% ~55%
Space saving
MV GIS Smaller Than MV AIS – Compact Footprint
Single bus
Page 10
comparison

• Tested to ANSI/IEEE C37.20.7-2007/IEC 62271-200 for
internal arcing faults
• Arc-resistant internal arc classification type 2B
(front, side, rear with low-voltage compartment
door open)
• Reduced level of PPE permitted by NFPA 70E
for arc-resistant switchgear
Page 11
MV GIS Is Tested For Arc Resistance

Comparison of PPE3 level required foroperations
Activity MV air-insulated switchgear (AIS)1 MV GIS
Open/close
circuit breaker
HRC 2 (door closed)2
HRC 4 (door open)
HRC 04
Isolate circuit
HRC 4 (racking, door open or closed)
(Note: isolation in metal-clad requires
racking to test or disconnect position)
HRC 0 (operation of
three-position switch to
open position)
Application of
safety grounds
HRC 4 HRC 04
Page 12
1 Non-arc-resistant.
2 HRC = hazard risk category HRC 0 = lowest level HRC 2 = 8 cal/cm2 PPE HRC 4 = 40 cal/cm2 PPE.
3 Derived from tables 130.7 (c) (15) (a) in NFPA 70E-2012. Refer to NEC 70E for detailed requirements.
4 HRC 0: non-melting or untreated natural fiber-protective clothing, long-sleeved shirt, long pants, safety glasses or goggles,
hearing protection.
For Major Operational Activities
Reduced Level Of PPE Can Be Used For MV GIS

UL/cUL Listed* as
arc resistant to
ANSI/IEEE C37.20.7-2007
* Ratings dependent
UL Listed*
Page 13

Low-voltage
compartment
Page 14
Busbar
Drive mechanism/
three-position switch
Gas monitoring
Drive mechanism/
circuit breaker
Circuit breaker
pole housing
Current transformer
Cable connection
from the bottom
Circuit Breaker Section (8DA10 Single Bus Shown)

Busbar housing
Three-position
switch (shown OPEN)
Pole housing
Busbar Design Up To 5000 A
Busbar 5000A
Busbar up to 4000A
Busbar
Busbar
Twin busbar housing
Busbar
Page 15

Three-Position Selector Switch
OPEN
Page 16
READY-TO-
GROUND
CLOSED

• Compact – same footprint from
2.4 kV to 42 kV
• Gas insulation eliminates derating
due to altitude
• Video camera system to view three-
position switch status – complies
with NEC visible disconnect
requirement (NEC 225.51 &
230.204)
• Capacitive voltage indicators –
avoids need for hot-stick for
checking energization of primary
• Integral grounding switch –
grounding cables are unnecessary
Overview of innovative features
Innovative Features
Page 17

8DA/B ANSI
Camera housing and mounting
Page 18

8DA/B ANSI
Hardware
 RJ45 (ethernet) and USB
connector on laptop necessary
 USB-A 2.0 or 3.0
 Ethernet
Ethernet connection
USB interface
Screw caps for protection
1
3
2
Page 19 2014 IC1000-F320-A121-X-4A00 Murtaza Khan MS U.S.

8DA/B ANSI
Software
 No special software tool and
software expertise required
 Only web browser is needed
 Mozilla Firefox
 Microsoft Internet Explorer
 Google Chrome
 Safari
 Other browsers might work,
but are not covered with
development tests
Ethernet connection
USB interface
12
3
Page 20

8DA/B ANSI
Operation
 Open screw caps (at switchgear front or
rear wherever it is applicable)
 Connect USB and RJ45 plugs (between
switchgear interface and laptop, cables
are supplied)
 Start web browser and type in any
address
 Three reference pictures on top view
(CLOSED, OPEN, GROUNDED)
 Camera live-view below
 Three software buttons available to
switch view from phase L1, L2 and L3
Ethernet connection
USB interface
1
3
2
Page 21

View Port Via Video Camera
Page 22
Use of PC to
view position of
selector switch

C2
C1
Potential
indicator
or
indicator
Capacitively Coupled Voltage Indication System
Page 23
• Coupling electrode built into pole-support
plate of the circuit breaker
• For checking the energization state ofeach
pole
• No hot stick required to check voltage
presence
Plug-in LRM voltage indicator

Circuit
OFF &
ISOLATED
Ready To
Ground
Circuit
GROUNDED
Circuit
CLOSED
Three-Position Selector Switch
Page 24

Lockout/Tagout
Page 25

• Sealed pressure system protects
against environmental influences
(IP65)
• Single-pole enclosure eliminates
possibility of phase-to-phase faults
inside switchgear
• Division of gas compartments
enables rapid problem isolation
• Mean time between major failure:
• MV GIS — 5,300 years
(based on last 10 years data)
• MV AIS — 856 years (estimate)
Sources: IEEE 493 Gold Book (for MV AIS), Siemens internal data (for MV GIS)
Overview of reliability features
High-Operational Reliability
Page 26

Source: IEEE 493 Gold Book, Annex E, table XVIII, page 479
• Thermocycling
• Mechanical structure failure
• Mechanical damage from foreign source
• Shorting by snakes, birds, rodents, etc.
• Malfunction of protective device
• Above normal ambient
• Exposure to chemicals or solvents
• Exposure to moisture
• Exposure to dust or other contaminants
• Exposure to non-electrical fire
• Normal deterioration from age
• Severe weather condition
• Others
7%
3%
7%
3%
10%
3%
3%
30%
10%
7%
10%
3%
4%
Share
Not applicable
to MV GIS





Estimated
50% of
failure
causes
not
applicable
with
MV GIS
Page 27
OverviewoffailurecausesforMVAIS
Reduces Or Eliminates Causes Of
50% Of Failures In MV AIS
MV AIS
failure cause

• Vacuum interrupter mounted in
circuit breaker pole housing
• Non-sliding current transfer from
vacuum interrupter moving contact
to three-position switch
Page 28
Vacuum Interrupter

Ring-core current
transformers:
• Current transformers
located outside gas
zone
• Secondary part
accessible outside
the enclosure (& gas
zone) without
exposure to primary
voltage
• Free of dielectrically-
stressed cast-resin
parts
A
C
B
A
Page 29
Current Measurement
Current transformer
installation
(basic scheme)
Item Description
A
Feeder current
transformer on the
cable housing
B
Feeder current
transformer on the
cable
C
Busbar current
transformer

• Mounted separately & connected via a
plug-in cable
• Grounded metal-enclosed
• Connected line-ground
• VT solid insulated with grounded metal-enclosure
• Outside main circuit
• Fused
• No gas work required to remove or install
Voltage transformer
with primary fuse
Line-Side (Cable-Side) Voltage Transformer
Item Description
1 Bus connected VT
2 Cable connected VT
1
2
Page 30

• Internal cone type plug-in connections
per EN-50181/DIN 47637
• Sizes available up to 1,250 A per
conductor (cable) and up to
2,500A for cast-epoxy insulated bus
• Size 2, up to 40 mm (1.57”) O.D.,
up to 800A
• Size 3, up to 46 mm (1.81”) O.D.,
up to 1,250A
• Size 3.5, up to 50 mm (1.97”) O.D.,
up to 1,250A
• Diameter is over insulation, without
voltage detection tap
Page 31
Plug-In Cable Termination System

Low Maintenance Over Life Cycle
Page 32
Types 8DA10/8DB10
Visual inspection Every 5 years
Condition
inspection
Every 10 years
Maintenance
After 1,000 operating cycles of the disconnectors &
grounding switches or after 10,000 operating cycles ofthe
circuit breaker.
These intervals are guidelines which have to be adjusted to the different operating conditions
(i.e., dusty environment, frequent condensation, etc.) which can affect operating mechanism

Maintenance Checks
Page 33
Visual
inspection
Condition
inspection
Maintenance Description
X X X Check & document SF6 gaspressure
X X
Check & document dew-point (humidity
content) (≤15 ˚C)
X X
Check & document gas quality
(air content) (SF6 share ≥95%)
X
Check operating mechanism & interlocking
of disconnector & grounding switch. If
required, grease linkage & bearings.
X
Vacuum circuit breaker operating
mechanism

Dielectric withstand
in relation to gas
pressure/leakage
(example: 38 kV)
Gas pressure(abs.)
0/100 50/50 100/0 1.0 1.3 1.5 1.7 bar
200
50
SF6 / air mixture (%)
SF6 at gauge
pressure
0
100
ANSI rated 60 Hz withstand 80
ANSI rated impulse (BIL) 150
30
Switching under
normal conditions still
possible
Dielectric Withstand
Normal atmospheric pressure
Page 34

ReliabilityFootprint
Maintenance
MV AIS
Consider not just the one-time purchase cost,
but also the total life-cycle cost
Spare Parts
MV GIS
Safety
Consider These Investment Decision Advantages

Questions Answers
Can the circuit breaker interrupt if
there is a leak and no SF6 gas is
available?
Yes, the vacuum interrupters are
independent of the SF6 gas and all the
interruption occurs inside the vacuum
interrupters. SF6 gas is only used for
insulation.
What is the SF6 leakage rate in
Siemens MV GIS 8DA/B?
The low leakage rate is possible as
the normal pressure is 1.5 bar (22
psig) or less, and the SF6 gas is used
only for insulation, not for interruption.
Leakage is below 0.1% per year.
Page 36
Go-To-Market
FAQs

Questions Answers
Is SF6 a greenhouse gas“GHG”? Yes, SF6 is a GHG with atmospheric
lifetime of 3,200 years.
Are there any taxes applicable on use
of SF6 gas in MV switchgear or any
regulatory requirements?
No, users are required to report
annually SF6 volume if their inventory
exceeds 17,800 lbs at any time.
How do I quantify 17,800 lbs of SF6
gas in terms of number of sections?
8DA10 ~ 2,700 sections
8DB10 ~ 1,400 sections
What is the percentage ofemissions
of SF6 gas from T&D equipments
compare to the total emissions of all
the gases in the U.S.?
In 2013, total emissions of all GHG
reported was 5,791.2 MMT CO2
equivalent. Emissions from T&D
equipments were 5.1 MMT CO2
equivalent. Net emission from T&D
equipment was < 0.1% (5.1/5,791.2)
Page 37
Go-To-Market
FAQs

Reference project in Utility/IOU
Page 38
Customer information
 Customer: Georgia Power
(Demo Unit)
 Location: Georgia
Project information
Equipment type: 8DB
 Number of sections: 4
 Voltage: 25 kV
 Short-circuit current: 40 kA
 Year of installation: 2009

Reference project in Pharmaceutical
Page 39
 Customer: Amgen, Inc.
 Location: Washington
Project information
 Equipment type: 8DA
 Number of sections: 50
 Voltage: 4.16 kV and
26.4 kV
 Short-circuit current: 40 kA
 Year of installation: 2001

Reference project in Heavy Industry/Manufacturing
Page 40
 Customer: Caterpillar, Inc.
 Location: Illinois
Project information
 Equipment type: 8DA
 Number of sections: 40
 Voltage: 13.8 kV
(shown during installation)

Reference project in Oil and Gas/Refinery
Page 41
 Customer: ConocoPhillips
 Location: Wood River,
Illinois
Project information
 Voltage: 38 kV

Reference project in Oil and Gas/Refinery
Page 42
 Customer: Hovensa
Refinery
 Location: St. Croix, U.S.
Virgin Islands
Project information
 Voltage: 38 kV

Reference project in Oil and Gas/Extraction
 Customer: Canadian
Natural Resources Ltd. -
Horizon Oil Sands
 Location: Alberta, Canada
Project information
 Voltage: 5 kV, 15 kV and
38 kV
Page 43

Reference project in Higher Education
Page 44
 Customer: NOVA
Southeastern University
Location: Florida
Project information
Voltage: 4.16 kV and 13.8 kV
 Short-circuit current: 40 kA
 Year of installation: 2009

Manufacturing Location
Siemens MV GIS Manufacturing in Frankfurt (SWF): The Home ofGIS!
Page 45

Page 46
GIS
compared to
AIS

Fixed-type, gas-insulated
medium-voltage switchgear
compared to air-insulated switchgear
T comparison
2016

MV AIS
Page 48
• Drawout type construction, where
circuit isolation is achieved by
opening the circuit breaker and
then racking it to the test or
disconnect position.
• No built-in circuit grounding
capability. Grounding of load
circuit requires drawout ground
and test device.
MV GIS
• Fixed-mounted circuit breakers
with interlocked isolation switch
and grounding switch. Isolation
meets NEC visible disconnect
requirement.
• Grounding accomplished with
grounding switch and circuit
breaker with fault-making
capability. Sequential
interlocking prohibits
mis-operation.
MV GIS Comparison To MV AIS

MV AIS
Page 49
• Drawout type construction,
requiring physical movement of
circuit breaker from connected to
test or disconnect position.
• Historic experience suggests
higher potential for failures
associated during racking.
MV GIS
• GIS achieves isolation without the
movement of the circuit breaker,
eliminating the potential for
misalignment.

Page 50
MV AIS
• Conventional-type cable
termination (cable lugs and stress
cones), exposed to contaminants
MV GIS
• Plug-in type cable termination,
which provides IP65 protection
and easy installation at site

Siemens MV GIS Advantages
Page 51
MV GIS
offers the
advantages
of a
switching
device -
a minimum
number of
parts
resulting in
a high
MTBF
1. No regular maintenance
1.Visual inspection: 5 years
2.Status inspection: 10 years
3. Maintenance after 10,000
operations
2. No impact from environmental
conditions (except for flooding)
3. Highest IP protection by having
IP65 for high-voltage parts.
4. Highest personal safety.
5. Operational safety
6. Compact design
7. No extra-storage space required
1. Saves costs - no shutdowns needed.
2. Saves insulators from dust;
provides constant insulation quality.
3. No penetration of foreign bodies like dust,
small animals and moisture.
4. High-voltage part installed in gas-insulated,
sealed housing so no access to high-voltage
parts. Fool-proof interlocks.
5. Low-maintenance switching device.
Cable grounding via the circuit breaker.
Risk of internal arcs minimized.
6. Up to ~75% space saving vs AIS.
7. Only a few small secondary spare parts
recommended.

Footprint comparison (MV AIS & MV GIS - only equipment size considered)
38 kV
15 kV
MV
AIS
MV
GIS
MV
GIS
MV
AIS
~75% ~55%
MV GIS Smaller Than MV AIS – Compact Footprint
Single bus
Space saving
Page 52
comparison

MV GIS Advantages - Maintenance
MV AIS
Required latest after 5 years of service:
• Switch off of lines, feeders and busbars
• Grounding
• All circuit breakers in testposition
• Test function of circuit breakers andand all other
switching devices
• Remove the drawout circuit breaker andremove
covers partly to access to busbars and cable
sections
• Clean the sections and all insulation, and check all
bolted connections
• Lubricate all bearings and surfaces; check panel
function and put switchgear back intoservice
Example:
Estimated time per section: 4 hours
For a 20-section lineup 80 working hours,
respective to 8 working days for maintenance
Average $180 per person per hour, i.e., $14,400
for a 20-section lineup
MV GIS
• Requires minimal maintenance
• Visual inspection: 5 years
• Check gas-pressure gauges
• General visual survey.
Example:
For the 20-section lineup, potential savings $14,400.
After 30 years, total savings $86,400
Page 53

MV GIS Advantages - Availability
MV AIS
• During maintenance, switchgear is out of
service.
• Provisions for alternative supply circuits
must exist.
• Switching procedures must be followed.
• After maintenance, original conditions need
to be re-established.
Risks:
• Switching failures.
• Network disturbances may occur.
• Human errors, tools left in equipment, loose
connections, loose bolts, missing covers,
etc.
Therefore, the risk of failures inside the
switchgear (including potential for arc
fault) may be higher.
MV GIS
• Almost maintenance free.
• No human errors can occur due to
hermetically- sealed isolation.
• Insulation cannot be contaminated.
Peace of mind
Page 54

MV GIS Advantages – Environmental Aspects
MV AIS
• Influence of dust, humidity and vermin to active
parts as busbars, breakers, cableconnections:
• Need of maintenance, cleaning ofinsulation
• Condensation – potential for partial
discharges and damage to insulation.
• Need to eliminate potential for verminin
switchgear
• Reduction in dielectric withstand (hipot and
impulse) for high altitudes
Example: 27 kV AIS at altitude of 6,562 ft (2,000 m)
needs rated insulation level of 138 kV BIL to provide
125 kV BIL at 6,562 ft (2,000 m). Since this cannot be
reached with 27 kV AIS, 38 kV AIS is required, which
means higher costs.
Additional costs and control are necessary.
MV GIS
• No environmental influences (flooding exception)
due to maintenance-free, hermetically sealed (HV)
switchgear.
• No influence of insulation level due to altitude.
Example:
Peace of mind and cost savings.
Page 55

MV GIS Advantages - Dimensions
MV AIS
For 27 kV, 2,000 A, 25 kA, AIS dimensions:
• Width: 3.0 ft (.91 m)
• Depth: 8.0 ft (2.4 m)
Floor space per section is equal to 24.0 ft²
(2.2 m2)
Example:
20-section lineup, area required:
• 480.0 ft² without required rear aisle
• 840.0 ft² with NEC clear working space in
rear.
MV GIS
For 27 kV, 2,000 A, 25 kA GIS dimensions:
• Width: 1.97 ft (.6 m)
• Depth: 5.3 ft (1.62 m)
Floor space per section is equal to 10.4 ft²
(1.0 m2) and no working space required at
rear
Example:
20-section lineup, area required:
• 209.0 ft² and no rear aisle required.
Page 56
Savings Value
271 ft2 without rear aisle $13.6 k to $180.3 k
631 ft2 with rear aisle $31.6 k to $419.8 k
Source for $ per ft² :http://www.businessinsider.com/us-city-

Aisle space
“I have to double the substation MVA,
but don’t have the space?”
38 kV switchgear
space requirements
single bus comparison
Air-insulated switchgear
99.3 ft2 = 9.2 m2
Gas-insulated switchgear
22.7 ft2 = 2.1 m2
48” (1,219)
130” (3,302mm)
Page 57
72” (1,827 mm)
aisle space (NEC)
64” (1,626mm)
24” (610mm)
72” (1,827 mm)
minimum rear access(NEC)
96” (2,438mm)
drawout space
Space Problems? MV GIS Advantages
*
* No rear access required,
eliminating need for rear aisle

MV GIS Advantages - Reliability
Source: IEEE 493 Gold Book, Annex E, table XVIII, page 479
• Thermocycling
• Mechanical structure failure
• Mechanical damage from foreign source
• Shorting by snakes, birds, rodents, etc.
• Malfunction of protective device
• Above normal ambient
• Exposure to chemicals or solvents
• Exposure to moisture
• Exposure to dust or other contaminants
• Exposure to non-electrical fire
• Normal deterioration from age
• Severe weather condition
• Others
7%
3%
7%
3%
10%
3%
3%
30%
10%
7%
10%
3%
4%
Share
Not applicable
to MV GIS





Estimated
50% of
failure
causes not
applicable
with
MV GIS
Page 58
MV AIS
failure cause
OverviewoffailurecausesforMVAIS

MV GIS Advantages – 150 kV BIL
MV AIS
Due to the requirement of 150 kV BIL at
27 kV, the switchgear selection should be
upgraded to the next voltage level.
This BIL value cannot be reached with
typical 27 kV switchgear.
Therefore, 38kV switchgear is required,
which means higher costs for the
customer:
• Higher equipment costs
• Much higher costs for real estate.
MV GIS
• Same design & footprint for voltages up to
40.5 kV
• No environmental influences due to
maintenance -free, hermetically-sealed
(HV portion) switchgear.
Cost savings.
Page 59

MV GIS Advantages – Spare Parts
MV AIS
For an estimated lifetime of 30 years, spares
needed.
•Lubricants
•Screws
•Bolts
•Nuts
•Contact fingers for draw out unit
•Isolators
•Bushings
Therefore additional cost for spares,
storage , handling, installation of parts,
staff for exchange the parts incurred.
MV GIS
Few small secondary parts recommended.
Cost savings due to minimal cost of
spares, no additional storage room,
handling cost and cost of staff.
Page 60

Siemens Medium-Voltage Gas-Insulated Switchgear Technical Overview

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