Training Course NX-Air Intro & Safety

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TRAINING COURSE COMPLIMENTS CATALOGUETRAINING COURSE COMPLIMENTS CATALOGUETRAINING COURSE COMPLIMENTS CATALOGUETRAINING COURSE COMPLIMENTS CATALOGUE
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NX-Air_M_P Training Intro Doc Sasol.doc
1006884 - N. Inderbiethen Page 2 25.09.2012
First Line Operation & Maintenance – Training Course
Siemens Vacuum Switchgear Type "NX-Air W / M & P"
Index
INTRO An Introduction to Vacuum Technology
A BRIEF INTRODUCTION TO THE SIEMENS VACUUM CIRCUIT BREAKER MANUFACTURING
PROCESS AND A TECHNICAL OVERVIEW OF THE ARC PRINCIPLE AND DESIGN PHILOSOPHY
BEHIND THE CONCEPT OF "VACUUM ARC INTERRUPTION" AND THE SCIENCE INVOLVED TO
ACHIEVE ONE OF THE HIGHEST GRADES OF TRUE "HIGH QUALITY ELECTRICAL SWITCHING
PRODUCTS" AVAILABLE TODAY…
1. Safety Instructions
2. NX-Air W / M & P Switchgear Description
in an introductory slide-show format
3. NX-Air All Types Descriptive Catalogue
4. NX-Air M & P Contactor Panel
5. NX-Air & NX-Air P Circuit Breaker Panel
6. 3AH & K (new) Vacuum Circuit Breakers
7. Vacuum Circuit Breaker Type: 3AH-1
10. Breakers Interrupter Table, Harting plug
description & Breaker-Mech Wiring Dwgs.
11. Sion Circuit Breaker Manual
12. Vacuum Contactor Slideshow
13. 3TL Vacuum Contactors Group Manual
14. 3TL 6 Vacuum Contactor Manual
15. 3TL 8 Vacuum Contactor Manual
16. Vacuum Contactor HR Fuse Types
17. Motorised Racking Manual for NX-Air M
18. Modular Metering & VT Truck Manual
19. Internal Arc Protection Scheme
20. Earthing Switch Operation for NX-Air P
21. Panel, C/B & Contactor Test Sheets
22. Circuit Schematic Drawing of Incomer
23. Circuit Schematic Drawing of Bus-section
24. Circuit Schematic Drawing of Meter Panel
25. Circuit Schematic Drawing of Feeder
26. Circuit Schematic Drawing of Motor Panel
27. Siemens Notepad / Drawing paper

Vacuum switching technology Arc quenching
During the galvanic separation of the contacts, the current to break produces a metal-vapour
arc discharge. The current flows through this metal-vapour plasma until the next current
zero. Near the current zero, the arc extinguishes. The metal vapour loses its conductivity
after few microseconds already the insulating capability of the contact gap recovers quickly.
To maintain the metal-vapour arc discharge, a specific minimum current is required. If this
minimum current is not reached, it will chop before the natural current zero. To prevent
impermissible switching overvoltages while switching inductive circuits, the chopping current
must be limited to the lowest possible values. Using a special contact material, the chopping
current in vacuum circuit-breakers is just 2 to 3 A. Due to the fast recovery of the contact
gap, the arc is safely quenched even if the contacts are separated right before a state of
"current zero". Therefore, the arcing times in the last pole to clear are 15ms as a maximum.
Depending on the breaking current and the interrupter dimensions, different contact
geometries are used.
Welcome to Siemens Technology
The history of Siemens's manufacture of various types
of circuit breakers recently achieved its first century. In
the past hundred years a very thorough knowledge of
all types of switching devices in every possible type of
medium have been researched, tested and tried.
So, it would be ironic if the technology which we now
call "vacuum" was not discovered during the global
space age. Unlike to normal air or mixtures of nitrogen
and oxygen a vacuum presents the perfect forum for a
safe switching environment being able to minimise
arcing and contact burn.

Key to description of parts:
IInntteerrrruupptteerr DDeessiiggnn
The interrupters are of a very compact
design as can be seen in the cross-section
drawing provided. The area or volume of
space occupied within the interrupter is at a
perfect vacuum state. This would be the
same as if switching the contacts in outer-
space, where there is no air, as in
"nitrogen" or "oxygen" which could
contribute in any way to assist with ignition
or explosive tendencies. This compact
design of the Siemens vacuum interrupters
provides a very high switching capacity in
very compact dimensions:
for example: vacuum interrupters for 15
kV/40 kA with housing dimensions of 125
mm diameter by 161 mm length, or for 12
kV/13.1 kA with 68 mm diameter by 115
mm length. A very high QA level has been
achieved in the product market. This quality
assurance is due mainly to Siemens
following the TQM and DIN / ISO 9001
procedures & specifications, which call for
rigorous material, manufacture &
production checking. Every batch is
checked & tested individually before
delivery and only if the QA result is a 100%
pass, are the interrupters released for
delivery. Some of the tests that are
performed include: testing of the
interrupters for assuring the seal of vacuum
sealing, testing for reliable long operation
and long life, environmental protection
involved in the manufacture of these
vacuum interrupters and our guarantee to
only use environmentally compatible
materials, such as copper, ceramics and
high-grade steel. Such, that the
manufacturing processes do not damage
the environment. (e.g. no CFC's are used in
production (this fulfilling the Montreal
agreement); also all the components are
cleaned and kept free from micro-fibres &
contamination in a ultrasonic plant, with the
entire manufacturing line concealed in a
protected atmosphere.
Vacuum interrupters for the medium-voltage range are available from Siemens for all applications on the international market from 1 kV
up to 40.5 kV. Vacuum Interrupters are also used in special design applications where the operational voltage that they are exposed to
is well in excess of 40.5kV, even up to as high as 132kV. When used in these applications the interrupter is immersed in SF6 Gas within
a pressurised chamber, so that the switching of "contacts" are still done within a vacuum inside the interrupter, but therefore in this
application the entire interrupter itself is immersed and insulated by SF6 gas. This type of configuration enables using the same
switching technology in much higher operational voltages.
Applications:
Vacuum interrupters are used in vacuum circuit breakers, vacuum switches, vacuum contactors, transformer tap changers, in circuit
breakers for use in railway applications, auto-reclose switches, and lastly also in special applications such as nuclear fusion.
Introduction to the Vacuum interrupters

Inside the Vacuum interrupter - The Manufacturing process
To prove the atmospheric pressure, in 1654 Otto von Guericke
created a vacuum with the Magdeburg hemispheres for the first
time in history. More than 35 years ago, Siemens developed
vacuum switching technology, leading it to series production.
What was then a fundamental innovation has been developed
further to a proven technology, which now has a worldwide
market share of about 70 percent. Vacuum switching
technology from Siemens meets all the requirements placed on
circuit-breakers and contactors in medium-voltage switchgear
up to 40.5 kV, and is now an integral part of many applications
because of its clear advantages.
The Siemens vacuum interrupters are manufactured inside the Siemens Factory in Berlin under various processes. We
will briefly take you on a short journey through this process and discuss some of the important facts of how these
vacuum interrupters are made until they are assembled in the form of a finished product such as a Contactor or vacuum
circuit breaker.
Contact rod processing
In our numerically controlled multi-axis lathes, the raw parts are given
the external contour and the slots of the contact carrier surface in just
one single operation. The fully automatic process reduces the error rate
to a minimum. A constantly high quality characterizes the produced
parts.
Contact material processing
Siemens is the only manufacturer of vacuum interrupters worldwide to
produce the contact material itself. The basic raw materials copper and
chrome are combined to a powerful contact material by means of the
arc-melting procedure. The resulting raw parts are processed to RMF or
AMF contact discs, whereby the slotted AMF discs are de-bured at the
end. All processing steps are electronically recorded for quality
purposes.
Metallography
To fulfil the highest quality demands, samples of the contact material are
examined by metallography. Here, the homogeneity of the contact
material, the quality of the melting process as well as the brazed
connection between the contact material and the contact rod are
checked.
Endurance test for bellows
To enable them to meet the requirements for high endurance in real
practice, the bellows are regularly subjected to an endurance test every
three months. The test is carried out in a fully automatic test cabin with
the travels adjusted to the respective type.

Vacuum interrupter assembly under clean-room conditions
After having finished and cleaned the surfaces by electroplating and
performed an optical inspection of the surface consistency of all single
parts, the interrupter is assembled. The high-vacuum solder is applied at
the joints of the components, the parts are aligned, and the interrupters
are fixed. As cleanliness during assembly is especially important, all
operations are done under air-conditioned "clean-room atmospheric"
conditions – in this way we can guarantee a constantly high quality of the
interrupters and maximum possible ratings up to 72 kA according to
IEEE C37.013.
High-vacuum brazing furnace
In the high-vacuum brazing furnace, the joints of the vacuum interrupters
are brazed at temperatures up to 900 °C and a press ure of 10-6 mbar.
Thus, the interrupters fulfil the quality requirement “sealed for lifetime”.
Thanks to the fully automatic production process, the high quality can be
constantly reproduced at any time.
X-ray test
The evaluation of the interrupters by means of the X-ray procedure is
used to verify the positions as well as the completeness of the internal
components, and the quality of the brazing points. In this way we ensure
the high quality of our products.
Forming and high-voltage testing of vacuum interrupters
During forming, the definitive internal dielectric strength of the vacuum
interrupter is established with gradually increasing voltage, and this is
verified by a subsequent lightning impulse voltage test. Both operations
are done with higher values than those specified in the standards, as
evidence of the extraordinary quality of the Siemens vacuum
interrupters. This is the prerequisite for a long endurance and a high
availability.
Switching device production
The switching device production is set up as a direct flow production.
Various assemblies are prefabricated in parallel and combined at the
mounting place of the switching device. The flow production reduces the
order lead times and thus the delivery times of the switching devices to a
minimum.
Laser welding
Laser welding provides a completely positive material joint between
individual components – as a prerequisite for highly resistant,
dynamically stress able assemblies such as the operating mechanism
box. Its superiority over conventional welding becomes apparent, above
all, by the fact that no hollows are produced – which would be
susceptible to humidity – and that the material cannot loose shape
anymore. The consequence: a high dimensional accuracy with the
lowest tolerances possible – and thus, reduction of later adjustments to a
minimum.
Stamping and laser cutting
In the pre-production, the steel plates are processed by highly automatic
and highly productive stamping and laser cutting machines – providing
the assured adherence to minimum tolerances, even with high
quantities. The high degree of automation results in a process-safe,
trouble-free production with short lead times, almost without any down
time. Loading, operating and programming is possible with the machine
running, without interrupting the production process.

Surface Treatment
Electroplating is used to improve the material surfaces and to protect
them against corrosion. By plating with a second material, the
mechanical and electrical properties of the carrier materials are
sustainably improved. This provides an optimised surface – which is
decisive for a longer service life of the product and its permanently
maintenance-free design.
Final assembly of switching devices
For all switching devices, the individual constructional units are pre-
assembled in parallel. During final assembly, the different constructional
units, the pole structure as well as the operating mechanism box are
combined, and the device is equipped with the order-specific secondary
system. Parallel work operations reduce the production lead time of the
switching device to a minimum – sometimes even short-term customer
requirements can still be implemented.
Final inspection and testing of circuit-breakers
After having passed the routine and high-voltage tests successfully, the
circuit-breakers are inspected at the final testing station to detect visible
sources of faults. The rating plate is not attached until this last visual
inspection has been completed successfully, and then the circuit-breaker
is released for dispatch. To reduce complaints to a minimum, the order is
checked for completeness and conformity before leaving – after all, you
are expecting quality in every detail.
& finally the finished products:

The Electro- Magnetic Concept of how a Vacuum Interrupter works:
Definition of a Vacuum Interrupter:
A vacuum interrupter is an operable single contact that has been
homogeneously sealed during its manufacture, in such a way that
the atmosphere within the interrupter, which would normally be
present around the contact surfaces, has been totally withdrawn
or "sucked out" of the inside chamber and then simultaneously
sealed immediately thereafter. In this sealed form there is then no
atmosphere, particles that may be ionized, or any gases present
that may contribute to igniting any type of flame or burning from
an arc around any of these contact surfaces inside the
interrupter. This making it almost impossible for any combustion
or burning to take place during the arcing-time that would usually
occur during an "on" or "off" operation of the circuit breaker.
The interior part of the interrupter is therefore at total vacuum
potential, i.e. equivalent to the conditions that would normally be
found in outer-space. The top pole contact of the interrupter is
usually fixed and the lower contact is the one which moves up
and down to achieve the operation. The interrupters on a circuit
breaker truck are usually 3 that are mounted side by side for the
3 phases usually required for industrial electrical operations on
plants. Vacuum Interrupters are also hugely environmentally
friendly, as they will maintain and contain all their lifetime of
switching gasses and debris, inside their own sealed housing
during their full service lifetime, which can range up to 25 years
pending certain operational circumstances. During operation
vacuum interrupters are also themselves not affected by the
environment, as they have been completely sealed with special
materials such as porcelain.
Philosophy of the -
In radial magnetic-field contacts, the arc burns diffusely until approx. 10 kA (momentary value). Higher currents
burn across a contracted arc. In this case, local overheating of the contacts must be avoided. An additional
magnetic field thus produces this required force, which makes the arc rotate on the arcing rings of the contacts
via the magnetic field generated by the flow of current through the contact tips. Thus, contact erosion at the base
point of the arc is distributed over the entire ring surface at a completely even rate.

Philosophy of the -
In axial magnetic-field contacts, the arc remains diffuse, even with high currents due to the axial magnetic-
field. The disc-type contact surfaces are uniformly stressed, and localised melting is avoided. In alternating-
current circuit breakers, the actual function of the quenching system is to de-ionize the contact gap
immediately after current zero. For all conventional quenching systems, this means that the arc must already
be cooled before reaching the minimum quenching distance and the following current zero. Involuntarily, this
increases the arc's power a lot (magnetic component), resulting in it responding better to following the
magnetic field that develops between these two contact surfaces . In the case of vacuum circuit-breakers,
however, the arc is not cooled down. The metal-vapour plasma is highly conductive. This results in a very
small arc voltage ranging between 20 and 200 V. For this reason, and due to the short arcing times, the
energy converted in the contact gap is very low. Because of this relatively low stress, the quenching system
is maintenance-free. In stationary condition, the pressures in the interrupter is very low – less than 10-9 bar,
so that contact distances of just 6 to 20 mm are required to reach a very high dielectric strength. Apart from
circuit-breakers, the vacuum switching technology can also be used in contactors and other type of switches
such as barrel switches. Today, more than 70% of all circuit-breakers installed in medium-voltage systems
are based on vacuum switching technology.
CROSS-SECTIONAL SIDE VIEW OF AN INTERRUPTER
HIGH-SPEED CAMERA SHOTS OF THE "ARC
DISSIPATION" ON A POLE CONTACT SURFACE OPENING
UNDER REAL FULL-LOAD CONDITIONS

Maintenance and servicing
Symbols used Operation symbol: Identifies an operation.
Asks the operator to perform an operation.
Result symbol: Identifies the result of an operation.
1.1 General instructions
Independently of the safety instructions given in these operating instructions, the local laws, ordinances,
guidelines and standards for operation of electrical equipment as well as for labour, health and
environmental protection apply, and these are to be complied with, in line with the latest Regulations. All
methodologies & actions applied to any services of the equipment or to repairs are to comply with specified
methods as described and discussed in the Siemens specific procedure relevant to the equipment and parts
in question. All work performed, whether on site or in the works, of whatever nature, must comply with the
ACT.
1.2 The Five Golden Safety Rules of Electrical Engineering
The Five Safety Rules of Electrical Engineering must generally be observed during operation of the products
and components described in these operating instructions:
Isolating.
Securing against reclosing.
Verifying safe isolation from all sources of supply.
Earthing and short-circuiting methods are safe & can withstand kA rating.
Covering, tagging and locking out of all adjacent live parts and shutters.
1.3 Delivery in line with Specifications
The switchgear corresponds to the relevant laws, prescriptions and standards applicable at the time
of delivery. If correctly used, they provide a high degree of safety by means of logical mechanical
interlocks and shockproof metal enclosure of live parts.

1.4 Qualified personnel – Training and legalities
Qualified personnel in accordance with these instructions, are persons certified or qualified to undertake this
type of work, either by certification through some form of education, studies, or training, which can be backed
up by a recognized certificate, degree, or letter of appointment. For such persons, or qualified Electrical
Artisans, Technicians and Engineers, that are permitted by their organisations, the National Regulator, or any
form of other legally acceptable appointments, who are similarly familiar with the regulatory requirements and
the safe operational safety requirements of these products and also have the appropriate qualifications for this
"type of work", must also obtain the necessary background knowledge about the transport, installation and
commissioning of these products. Therefore these personnel must have also participated in this training course
for "The first line safety, operation and maintenance" requirements of the Siemens air-insulated medium-voltage
switchgear type "SIMOPRIME".
The aim of this training, is that it provides a firm basis of "safety awareness, knowledge and understanding of
the equipment" in the form of detailed information about the design, operation, installation, testing and
troubleshooting of the SIMOPRIME switchgear. After successful participation, the participants of this training
course get a certificate of Competence to operate and perform the first line maintenance for this "specific" type
of equipment only, as the minimum required training for performing operations on specific electrical apparatus,
or as usually specified under the regulation, the Act or by the D.O.L.
The certificate for this course only authorises the participants to be appointed to "switch" or "operate" the
Siemens "specific" equipment, but then also only after they have fully satisfied the D.O.L., the N.R.S., the Act &
any other regulatory requirements required by the law, to perform "MV switching", within their specific "place of
work", as the authorised or responsible person, and that he or she has been fully trained on all the precautions
and dangers that are associated with this specific process. The certificate of this training will only allow the
operator to switch "Siemens type Simoprime medium voltage switchgear" electrically, provided that he is
certified on HV Regulations, has a letter of appointment to do this switching for and on behalf of his/her
employer, and has been appointed by letter, as the Operational or Responsible person to do such.
The attendee therefore acknowledges and realises, that by signing the attendance register, that it is up to his
"own full responsibility" to ensure his/her understanding of the subject matter, credible certifications to perform
the work and understand and apply the regulatory requirements, that are covered herein, so that at the end of
this course, they do not leave the venue with any remaining questions or uncertainties, to ensure that he or she
has satisfied their every curiosity, or remaining questions that they may have had, in terms of the Safety aspects
of the operations and functions of this equipment.
Siemens cannot be held liable, or will not accept any liability, or responsibility, for the direct or indirect actions
of any customer staff, that are out of, or beyond our control, supervision, or deviate from any regulation, even if
by accident or omission, or even if such procedures may be covered, yet have been misunderstood in this
training course which has been presented. It is the attendees own responsibility at the end of this course to
ensure that all the procedures and legal requirements of the NRS, the Act and any additional safety regulations,
such that may be required by such as even their employer, are all implemented, understood and upheld before
performing any work in the field.
The Completion of this course does not authorize staff to be appointed to do any "Switching". This is a separate
course on offer, which covers the regulations and the Act and is referred to as "High Voltage Switching
Regulations Training". For further information about this training, please contact: Niels Inderbiethen, on cell –
072 287 4525, who will arrange for a quotation for the course to be held either on our, or the clients own
premises.
We wish you a pleasant learning experience in attending this Siemens Training Course…
With our sincere thanks… from all of us… at…
SIEMENS LTD SOUTH AFRICA
Establishing safe conditions first, before the execution of any works

Furthermore, qualified personnel must have the following training and authorisation:
Training and instruction or authorisation to switch on, switch off, earth and identify
power circuits and equipment / systems as per the relevant safety standards (and the
recently added new requirements by law, such as HV Reg's & legal appointments)
Training and instruction about the relevant safety standards and the use of
appropriate safety equipment specifically relevant to the equipment they will be
switching (such as this course).
Training in first aid and emergencies behaviour in the event of possible accidents or
evacuation requirements relevant to their specific plant i.e. (plant specific)

1.5 Discussion of the features within the 3AH & K (New) operating mechanism.
The operating mechanism is fitted with an integrated mechanical interlock which prevents dangerous
switching conditions or operations from being carried out when the power is on.
The operating mechanism unit is only found on trucks fitted with a circuit-breaker.
The mechanism is fitted with isolating contacts that indicate the breaker position during racking.
Mechanical interlocks are provided to safeguard the operator during racking procedures.
Visual racking control status is provided with graphic representation.
The operating mechanism is fitted with a closing solenoid allowing for remote "close" control.
Mechanical indication of “closing spring charged” indicator can be seen through front of truck cover.
The first shunt release coil, which is also used for remote tripping, is the electrical tripping solenoid which
mechanically pushes against the trip lever that triggers the trip roller bearing.
The mechanism is fitted with an operating cycle counter, which counts every open and then closed
operation as one single operation increment on the counter.
Other solenoids may also be additionally fitted to extend the conditions of the trip operations, these
include under-voltage coils and uniquely driven shunt-trip coils. The circuit-breaker tripping signal can
also be additionally routed through protection relays and logic contacts to extend the desired level of
protection.
The circuit breaker mechanism is fitted with an electrical anti-pumping device which prevents more than
one auto re-closure, when the breaker is switched back on a fault that has still not cleared.
Varistor module fitted for the auxiliary voltage W 60 V, the auxiliary switch has 6NO+6NC contacts.
1.6 Parts of the 3AH5 circuit breaker operating mechanism:

1.7 Nameplate:

1.8 SION vacuum circuit breaker.
Component Identifications:
Part identification & features of the SION Operating Mechanism.
Component Identifications:

Maintenance and servicing
1.9 General Maintenance
The vacuum circuit-breakers / contactors switchgear are maintenance-free within the scope of the
permissible number of operating cycles. Under normal environmental and operating conditions the
maintenance intervals are longer than five years. Built-in equipment such as voltage transformers,
current transformers, relays, meters, protection equipment, etc. must be serviced and maintained as
specified in the associated operating instructions.
Commercially available tools are sufficient for carrying out the maintenance work.
After maintenance, put the equipment again into operation as per the operating instructions.
Carry out maintenance and servicing at shorter intervals (to be specified by the owner) if
there is a lot of dust, or if the air is extremely humid and/or polluted.
Grease main fixed contacts of bushings and fixed contacts of earthing switches as well as
other surfaces exposed to friction (e.g. shutter operating linkage, guide rails) at shorter
intervals (to be specified by the owner): Tin of Long-term 2 grease (8BX1022).
Independently of the regular maintenance, immediately determine the cause of faults and
short circuits and replace any damaged components.
Maintenance intervals
The maintenance intervals described hereafter are a recommendation when the switchgear is
operated under normal environmental conditions. In case of extreme operating conditions the
maintenance intervals must be adjusted accordingly.
Annual maintenance
Carry out general check for damages, dust layers, humidity in the switchpanels, and for partial
discharge noises.
Check whether accessories are complete and in good condition (including the truck).
Maintenance after five years
Operate earthing switches for test.
Clean switchpanels.
Check function of switchpanels and put switchgear again into operation.
Check primary connections of current and voltage transformers.
Check bolted joints (see "Installation", Section 9.2, Page 32).
SAFETY FIRST - Maintenance of vacuum circuit-breaker / vacuum contactor
Preconditions: • Supply voltage switched off
• Circuit-breaker in OPEN position
• Spring not charged

Niels Inderbiethen
Specialist – Technical Support
FAC/ASS ETDPSETA SAQA AcrNo:ATS/12/2838
MCS (Metering) & PTI (Training) Services
SG Services (Smart Grid)
Siemens Southern Africa
IC Sector (Infrastructure & Cities)
Newmarket Street, Northriding
T: +27 10 222 7315
F: +27 86 506 5941
M: +27 72 287 4525
niels.inderbiethen@siemens.com
www.siemens.co.za
- END OF THIS TRAINING ADDENDUM MANUAL -
NNB
(PLEASE REFER TO THE DIFFERENT NX-AIR W, M&P SWITCHGEAR PANEL
DOCUMENTATION FOR A FULL DESCRIPTION OF RACKING IN THE RACKING ORR
MOTORISED RACKING OPERATIONAL PROCEDURES.
ADDITIONAL INFORMATION ON THE CIRCUIT EXAMPLE DRAWINGS FOR THE
CUSTOMERS SWITCHBOARD (SINGLE LINE DRAWINGS AND THE 3AH CIRCUIT
BREAKERS WIRING DIAGRAMS) IS ALSO PROVIDED IN THE LAST SECTIONS,
SECTIONS 22-26 OF THIS MANUAL)

Training Course NX-Air Intro & Safety

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