Velatia Ormazabal transforma.plur Instruction manual

LIB
transforma.plur
Transformers with corrugated tank
and submerged in dielectric liquid
from 3150 kVA
General Instructions
IG-287-EN, version 03, 24/07/2020

In view of the constant evolution in standards and design, the characteristics of the elements contained in this manual are subject
to change without prior notice. These characteristics, as well as the availability of components, are subject to confirmation by
Ormazabal.
CAUTION!
When medium-voltage equipment is operating, certain components are live, other parts may be in movement and some may
reach high temperatures. Therefore, the use of this equipment poses electrical, mechanical and thermal risks.
In order to ensure an acceptable level of protection for people and property, and in compliance with applicable environmental
recommendations, Ormazabal designs and manufactures its products according to the principle of integrated safety, based on
the following criteria:
• Elimination of hazards wherever possible.
• Where elimination of hazards is neither technically nor economically feasible, appropriate protection functions are
incorporated in the equipment.
• Communication about remaining risks to facilitate the design of operating procedures which prevent such risks,
training for the personnel in charge of the equipment, and the use of suitable personal protective equipment.
• Use of recyclable materials and establishment of procedures for the disposal of equipment and components so
that once the end of their service lives is reached, they are duly processed in accordance, as far as possible, with the
environmental restrictions established by the competent authorities.
Consequently, the equipment to which the present manual refers complies with the requirements of section 11.2 of Standard
IEC 62271-1. It must therefore only be operated by appropriately qualified and supervised personnel, in accordance with the
requirements of standard EN 50110-1 on the safety of electrical installations and standard EN 50110-2 on activities in or near
electrical installations. Personnel must be fully familiar with the instructions and warnings contained in this manual and in other
recommendations of a more general nature which are applicable to the situation according to current legislation[1].
The above must be carefully observed, as the correct and safe operation of this equipment depends not only on its design but also
on general circumstances which are in general beyond the control and responsibility of the manufacturer. More specifically:
• The equipment must be handled and transported appropriately from the factory to the place of installation.
• All intermediate storage should occur in conditions which do not alter or damage the characteristics of the equipment
or its essential components.
• Service conditions must be compatible with the equipment rating.
• The equipment must be operated strictly in accordance with the instructions given in the manual, and the applicable
operating and safety principles must be clearly understood.
• Maintenance should be performed properly, taking into account the actual service and environmental conditions in
the place of installation.
The manufacturer declines all liability for any significant indirect damages resulting from violation of the guarantee, under any
jurisdiction, including loss of income, stoppages and costs resulting from repair or replacement of parts.
Warranty
The manufacturer guarantees this product against any defect in materials and operation during the contractual period. In the
event that defects are detected, the manufacturer may opt either to repair or replace the equipment. Improper handling of this
equipment and its repair by the user shall constitute a violation of the guarantee.
Registered Trademarks and Copyrights
All registered trademarks cited in this document are the property of their respective owners. The intellectual property of this manual
belongs to Ormazabal.
[1] For example, in Spain the “Regulation on technical conditions and guarantees for safety in high-voltage electrical installations” – Royal Decree
337/2014 is obligatory.

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General Instructions
transforma.plur: Transformers with corrugated tank
and submerged in dielectric liquid from 3150 kVA
Contents
Contents
1. Description and main characteristics.......................4
1.1. Design, manufacturing and testing ...........4
1.2. Individual or routine tests ....................4
1.3. Test protocol.................................4
2. Lifting, moving and handling ...................................5
2.1. Lifting and moving by crane .................5
3. Transport ..................................................................11
3.1. Preparing the load for transport .............11
3.2. Transport agents............................13
3.3. Selecting the route for road transport .......13
3.4. Checking impact detectors..................13
3.5. Liability.....................................13
4. Storage......................................................................14
5. Installation ...............................................................15
5.1. Receiving the transformer...................15
5.2. Transformer site.............................16
5.3. Transformer electrical connections ..........16
5.3.1. Standard procedure.........................16
5.3.2. Special transformers with electrostatic screen
between primary and secondary ............18
6. Start up .....................................................................19
6.1. Transformer check before commissioning....19
7. Maintenance.............................................................21
7.1. Access for maintenance operations ..........21
7.2. Transformer check ..........................21
7.2.1. Transformer temperature....................21
7.2.2. Oil volume inspection.......................21
7.2.3. Noise .......................................22
7.2.4. Tightening screws and threaded pieces......22
7.2.5. Oil leaks ....................................22
7.2.6. Paint........................................22
7.3. Regularity of maintenance ..................24
7.4. Repairs .....................................25
8. Additional information............................................26
8.1. Reliability ...................................26
8.2. Company registration certificate.............26
9. Final annex ...............................................................27
9.1. Tightening torques..........................27

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Description and main characteristics
General Instructions
transforma.plur: Transformers with corrugated tank
and submerged in dielectric liquid from 3150 kVA
1. Description and main characteristics
1.1. Design, manufacturing and testing
[2] Medium voltage electro-technical regulations applicable when the transformer was manufactured.
Ormazabal's transformers have been designed and
constructed in accordance with the mandatory standards.
They meet the testing requirements of the current medium
voltage electro-technical regulations[2], as well as customer
specications, in particular.
Figure 1.1. Detail of transforma.plur elements
More specically, apart from the mineral oil-immersed
transformers, the organic transformer range is characte-
rised by its use of natural biodegradable ester as a dielectric
liquid, with the following general characteristics:
• Excellent dielectric properties, with a high water
saturation point, which allows it to maintain high
dielectric rigidity values with a high water content.
• High re resistance : natural dielectric ester is
classied as a K class liquid (re point > 300 ºC)
according to Standard IEC 61100. This classication
oers the possibility of avoiding having to install
xed re extinguishing systems, according to many of
the medium voltage electro-technical regulations of
dierent countries.
• High biodegradability in soils and water due to its
natural composition.
• It is not ecotoxic.
• Recyclable and reusable in other favourable environ-
mental products at the end of its service life.
1.2. Individual or routine tests
The transformers are subjected to routine tests, which
guarantee compliance with the applicable standards:
• Winding resistance measurement.
• Transformation ratio measurement and vector group
check.
• Measurementof load lossesandshort-circuitimpedance.
• Measurement of losses and no-load current.
• Power frequency applied voltage test.
• Induced voltage test.
1.3. Test protocol
All the information regarding the transformer tests is
recorded in the Test Protocol enclosed with the transformer
documentation.

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General Instructions
transforma.plur: Transformers with corrugated tank
and submerged in dielectric liquid from 3150 kVA
Lifting, moving and handling
2. Lifting, moving and handling
The lifting elements must be selected based on the
transformer's total weight, as shown on the nameplate.
To enable lifting and transport, each transformer has
anchoring and hoisting elements on the top-side part of
the tank or on the tank's cover.
To secure the transformer during transport, there are
fastenings and boreholes on the bottom of the transformer
(slides and bottom).
CAUTION!
To lift, move or fasten the transformer to the transport
bed, the cooling elements (ns, radiators, etc.) must
NEVER be forced. All the force of these operations
must be supported by the fastening, moving and
hoisting elements (braces, etc.).
Transformers must be lifted, transported and handled using
suitable, approved means.
These lifting, transport and handling means and their use
must be chosen by the handler according to the machine's
characteristics.
Ormazabal is not responsible for an unsuitable choice or
use of such means.
2.1. Lifting and moving by crane
In order to lift and move the transformer by crane, it must
be taken into account that the lifting elements allow its
total suspension. These elements are the lifting eyebolts,
incorporated on the cover or on the top part of the sides
of the tank (depending on the transformer's weight)
and identied for this purpose (e.g., painted yellow). The
following indications must be taken into account when
lifting the transformer:
• Use the eyebolts on the cover or top of the sides of
the transformer tank to lift the transformer by crane,
maintaining a horizontal position at all times.
• Use proper hooks to achieve perfect vertical elevation.
• The slings on the eyes must form a minimum angle of
80° with the transformer’s horizontal.
• The slings must not rub or damage the bushings or
other accessories
• NEVER use transformer cooling elements such as ns or
radiators as lifting elements. RISK of severe injury and
damage to the transformer.
Danger of death by crushing and damage to the
transformer or to the installation.
• NEVER use transformer cooling elements such as ns
or radiators as lifting elements. RISK of severe injury
and damage to the transformer.

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Lifting, moving and handling
General Instructions
transforma.plur: Transformers with corrugated tank
and submerged in dielectric liquid from 3150 kVA
Figure 2.2. Detail of crane hook preparation in the eyebolts Figure 2.3. Detail of lifting a transformer by crane
The following indications must be taken into account when
completely hoisting the transformer:
• Transformers with eyebolts on the sides of the tank
- The lifting elements are used via the central hole
(Figure 2.4).
Figure 2.4. Lifting element

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General Instructions
transforma.plur: Transformers with corrugated tank
and submerged in dielectric liquid from 3150 kVA
Lifting, moving and handling
- The transformer has four lifting elements positioned
at the top of the sides for transformers with eyebolts
on the tank (Figure 2.5).
Figure 2.5. Position of the lifting elements
- ALWAYS lift the transformer using the four lifting
elements (identied in yellow) at the same time.
NEVER lift the transformer without any of these four
elements
- NEVER lift the transformer using the outside holes
(Figure 2.6)
Figure 2.6. Detail of position not permitted for lifting

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Lifting, moving and handling
General Instructions
transforma.plur: Transformers with corrugated tank
and submerged in dielectric liquid from 3150 kVA
- DO NOT use the transformer cover lifting elements
in transformers with eyebolts on the tank. These
elements are invalidated to prevent any use other
than to remove the transformer from the tank if this
is tted with lifting elements (see Figure 2.7).
Figure 2.7. Detail of area not permitted for lifting on cover if there are
eyebolts on the tank
- NEVER lift the transformer using the connecting rod
of the cooling elements (Figure 2.8)
Figure 2.8. Detail of area not permitted for lifting by the n connection
rod

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General Instructions
transforma.plur: Transformers with corrugated tank
and submerged in dielectric liquid from 3150 kVA
Lifting, moving and handling
• Transformers with eyebolts on the the tank cover
Whenever the lifting eyebolts are placed on the cover
because the weight of the transformer so allows, and
they are identied in yellow (Figure 2.9).
Figure 2.9. Eyebolts on the the tank cover
In the case of transformers of lower weight, two or four
optional eyebolts are available on the cover.
In the case of transformers with four eyebolts
considerably far apart, four lifting hooks must be used
simultaneously.
In the case of transformers with two eyebolts, or four
eyebolts very close together, two hooks with the
suitable means can be used. (Figure 2.10).
Figure 2.10. Position of the four eyebolts on the cover
Figure 2.11. Position of the two eyebolts on the cover

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Lifting, moving and handling
General Instructions
transforma.plur: Transformers with corrugated tank
and submerged in dielectric liquid from 3150 kVA
The slings or lifting chains in the eyebolts must also form
an angle equal to or above 80° with the horizontal of the
transformer, and must allow fully vertical lifting at all times.
• The slings must not rub or damage the bushings or
other accessories
• ALWAYS lift the transformer using the four lifting
elements, identied for this purpose. NEVER lift the
transformer without any of these 4 elements
• Using the n panel connecting rods as lifting points for
the transformer is NOT ALLOWED (Figure 2.12)
Figure 2.12. Forbidden lifting points

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General Instructions
transforma.plur: Transformers with corrugated tank
and submerged in dielectric liquid from 3150 kVA
Transport
3. Transport
Despite the robust design and construction of the
transformers manufactured by Ormazabal, their integrity
depends critically on the safety and protection measures
taken during transport and unloading. The transformer
can be severely damaged in these operations if shaking,
vibrations, impacts or knocks above normal for goods of
these dimensions and weight occur.
3.1. Preparing the load for transport
The transformer must be xed by means of slings, chains
and other elements suitable for the mass of the transformer,
as shown on its nameplate.
The protection tools and equipment provided or
recommended by Ormazabal (according to the agreement
with the customer), such as anti-vibration mounts and
suitable elements for pulling (braces) or fastening the load,
must be used for transport.
The transformer has specially designed lashing/fastening
elements to secure it during transport/handling operations.
• Top fastening elements: when provided, there are
four in total, located on the same structure as the
lifting elements (Figure 3.1) It is essential that chains,
hooks and pulling or lashing elements NEVER interfere,
collide or exert force on the cooling ns or radiators.
For this reason, they must be mounted at an angle
that prevents the collisions or interference described.
Figure 3.1. Top fastening elements

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Transport
General Instructions
transforma.plur: Transformers with corrugated tank
and submerged in dielectric liquid from 3150 kVA
• Bottom fastening elements: located at the base of
the transformer and used for the bracing or lashing
elements for transport. (Figure 3.2)
Figure 3.2. Bottom fastening elements
• When securing the transformer, make sure that the
lashing or bracing chains do not interfere with any of
the transformer's accessories or cooling elements.
• The fastening straps are attached to the container's
fastening elements on both sides of the transformer,
producing a symmetrical tension which is oset on both
sides.
• The connecting rods of the cooling elements must not
be used as lashing points for transport, or for any other
similar function (see Figure 3.3).
Figure 3.3. NEVER use cooling elements to fasten for transport

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General Instructions
transforma.plur: Transformers with corrugated tank
and submerged in dielectric liquid from 3150 kVA
Transport
3.2. Transport agents
All agents, companies and personnel involved in
transformer transport and handling tasks must demonstrate
due preparation, training, procedures and experience
in transporting heavy equipment which is sensitive to
damage from violent events during transport, as well as
having accreditations and aptitude certicates for driving
the means of transport used.
3.3. Selecting the route for road transport
The route chosen for road transport must be the one with
the best conditions for transporting heavy loads which are
sensitive to damage from impacts, shaking, vibrations and
accelerations.
Routes that reduce the eects of accelerations, vibrations,
impacts and shaking caused by winding roads, changes of
gradient and the camber of the road should take precedence
over shortest distance.
As far as possible, priority should be given to the highest
category of motorways with minimum slope, maximum
linearity and best road surface condition.
The transformers are prepared for at, paved road transport
without signicant potholes.
On stretches of rough roads, the transport speed must be
reduced to ensure that the load does not suer sudden
accelerations and decelerations.
In any case, the current trac and transport regulations
in each transit country must be abided by.
If the transformer's transport will include sections
of roads or routes o paved roads, with normal
conditions, the customer must inform Ormazabal
of this with the order. After this is informed, the best
solution for transport must be decided between the
customer and Ormazabal .
3.4. Checking impact detectors
Ormazabal reserves the right to t impact detectors (or ask
for them to be tted) in its transformers in order to provide
evidence of events that may cause damage to the machine
during transport.
In accordance with IEC 60076-1 in section 5.7.4.2
Acceleration during transport, the transformers referred to
in this manual are designed and constructed to withstand
accelerations of at least 1g in all directions (in addition
to the vertical acceleration of gravity) without damage.
If the transport is not managed by Ormazabal, and does not
fall within the scope of its responsibility, and accelerations
greater than 1g are expected during transport, the
accelerations and frequencies must be dened in the oer
request and the transformer must be designed according
to these values.
Ormazabal is not responsible for damage during transport
under transport conditions that exceed the values dened
in the standard or those specied when the oer and/or
order of the product are requested.
3.5. Liability
Ormazabal reserves the right to not be liable for any
damage caused when transporting and handling its product
if the conditions described in this general instructions
manual are not met.

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Storage
General Instructions
transforma.plur: Transformers with corrugated tank
and submerged in dielectric liquid from 3150 kVA
4. Storage
If commissioning is not immediate, transformers must be
stored following the recommendations below:
• Store the transformer horizontally in a clean, dry place
on rm, levelled ground.
• If the transformer is equipped with plug-in terminals,
make sure the conical protector or cap provided for
keeping the connection terminals clean and intact is in
place.

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General Instructions
transforma.plur: Transformers with corrugated tank
and submerged in dielectric liquid from 3150 kVA
Installation
5. Installation
Ormazabalis not responsible for transformer insta-
llation, which must be carried out in accordance with
applicable legislation.
5.1. Receiving the transformer
The transformer is supplied ready for connection to the
network. Some parts may be supplied dismantled for
transport.
When the transformer is received (at the customer
warehouse or at the transformer’s nal location), it must
be carefully inspected, paying special attention to the
following aspects:
• The transformer ratings, as indicated on its nameplate,
must match those in the "Test Protocol", and these, in
turn, must match those specied in the associated order.
• Check the general state of the transformer and ensure
the absence of any knocks, in particular on the cooling
equipment and the insulators or terminals. If the
transformer has paint defects, it must be corrected in
accordance with the procedure set out in section “7.2.
Transformer check” - “7.2.6. Paint”.
Notifythe transport agentand Ormazabalimmediately
if any accessory is missing or damaged.
• Check that the transformer has all of its accessories,
ensuring they are not damaged.
• If the transformer has security seals, these must be
unbroken and untouched.
Figure 5.1. Transformer seal
Any manipulation or breakage of a seal cancels the
transformer guarantee as well as Ormazabal's liability.
Notify Ormazabal immediately if any anomaly
is detected upon the receipt of the transformer.
If, after a 15 day period, we have not received a
report of anomalies or defects found, it is assumed
the transformer arrived in perfect conditions and
Ormazabal shall not be liable for any future anomalies
or their consequences.

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Installation
General Instructions
transforma.plur: Transformers with corrugated tank
and submerged in dielectric liquid from 3150 kVA
5.2. Transformer site
When the transformer has a dielectric liquid of plant origin:
Natural esters have higher freezing points than those
of mineral oil. Therefore, the liquid could freeze during
prolonged exposure to temperatures below 0 °C. In these
cases, the transformer can be powered without aecting
its physical-chemical properties. However, the transformer
should be protected from low temperatures during
prolonged storage periods.
The transformer site for both indoor and outdoor
installations must allow adequate cooling.
Poor ventilation of the transformer may cause it to
overheat.
Both the technical conditions and the personal and property
safety requirements of the transformer's design and site are
dened in the applicable legislation and standards.
A horizontal base that can withstand the transformer must
be prepared, bearing in mind its total weight, which is
shown on its nameplate.
5.3. Transformer electrical connections
5.3.1. Standard procedure
Risk of death by electric shock and of irreversible
damage to the transformer or to the electrical
installation.
• The transformer electrical connections can only
be performed by qualied personnel while always
observing the proper electrical safety measures.
The steps to follow to complete the electrical transformer
connection are as follows:
1. Check that the electrical power supply to the
transformer matches the service values shown on the
transformer’s nameplate.
Risk of causing irreversible damage to the transformer
or to the electrical installation.
• Verify that the electric power supply to the
transformer meets the service values indicated in the
transformer’s name plate.
2. Open all the electrical power sources and interlock or
block the necessary breaking devices to prevent the
power supply.
3. Check that electrical voltage is not present.
4. Earth and short-circuit all the electrical power sources.
5. Delimit and mark the work area properly.
6. Check the correct level of dielectric liquid and the
internal pressure of the transformer.
In the case of dielectric liquid leakages, contact the
manufacturer.

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General Instructions
transforma.plur: Transformers with corrugated tank
and submerged in dielectric liquid from 3150 kVA
Installation
7. Earth the transformer tank using round connecting
points for a standard cross-section earthing cable, as
well as an M12 bolt (M10 to order) and 2 14mm washers
(12mm for M10). Apply 40-60Nm of torque to the M12
(25-35Nm for M10).
Tools:
Standard cross-section earthing cable.
Round terminals of suitable diameter.
1 M12 (M10) bolt.
2 14mm (12mm for M10) washers (one for each side of
the connecting points).
Figure 5.2. Detail of transformer earth connection
Start the electrical connection by earthing the
transformer tank.
8. Connect the transformer to the medium voltage
circuit, or primary circuit. To prevent leaks, use exible
connections which do not place any strain on the
transformer bushings, suciently sized to prevent
excessive overheating and, at the same time, allow for
the dilatations caused by heat without damaging the
transformer.
The tightening torques must guarantee the proper
electrical contact of the connections.
9. Connect the transformer to the secondary circuit using
exible connections which do not place any strain on
the transformer bushings, suciently sized to prevent
excessive overheating and, at the same time, allow for
the expansion caused by heat without damaging the
transformer.
The tightening torques must guarantee the proper
electrical contact of the connections.
10. Connect the transformer’s neutral to the electrical
installation’s neutral (where appropriate).
11. Check that the tap changer position is correct; and,
in the case of a multi-voltage transformer, ensure the
medium voltage or primary circuit is connected to the
electrical voltage that is going to be used as service
voltage.

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Installation
General Instructions
transforma.plur: Transformers with corrugated tank
and submerged in dielectric liquid from 3150 kVA
5.3.2. Special transformers with electrostatic screen between primary and secondary
Transformers which are to be connected to renewable
generation plants (photovoltaic or wind) or to power
electronics equipment must have the following additional
considerations:
• Transformers may be tted with an internal electrostatic
screen to mitigate the eects of disturbance associated
with power electronics. The electrostatic screen must
have its connector bushing identied as P.E. or E.S. and
must be connected rigidly to the installation's earth
(preferably the protection earth, if there are two earth
installations).
Risk of death by electric shock and of irreversible
damage to the transformer or to the electrical
installation.
• If the transformer is tted with an electrostatic screen,
connect it to the installation's earth.
• The transformers may have more than one secondary
winding. Properly connecting the windings to the
dierent sources which will supply energy to the
transformer must be taken into account.
• Transformers with only one secondary can have
duplicate external connections for easier connection.
The correct distribution of power between them must
be taken into consideration.

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General Instructions
transforma.plur: Transformers with corrugated tank
and submerged in dielectric liquid from 3150 kVA
Start up
6. Start up
6.1. Transformer check before commissioning
Once the transformer is connected to the power networks,
and before connecting the electrical power source, the
following checks should be performed:
1. Check that the network values and the transformer
rated voltage match.
Natural esters have higher freezing points than those
of mineral oil. Therefore, the liquid could freeze during
prolonged exposure to temperatures below 0 °C. The
transformer can be powered in these cases, although
these situations should be avoided wherever possible.
2. If the machine has these instruments, check the correct
oil level on the oil level indicator or Buchholz relay.
3. Feed the no-load transformer and check its correct
connection and regulation by measuring the values
in the secondary. Where the transformer has natural
ester-type dielectric liquid and is powered after a
prolonged period of exposure to temperatures below
0 °C, the dielectric uid might be solid. Once the load
transformer has been powered, it will recover its usual
liquid stage.
4. Regulate the transformer's voltage using the
corresponding tap changer, taking into account the
following safety precautions:
Failure to follow these safety precautions may result in
death by electric shock or irreversible damage to the
transformer or to the electrical installation.
If the transformer has a natural ester as dielectric
liquid and has been exposed for a prolonged period
to ambient temperatures below 0 °C before being
powered, the uid might be solid. The tap changer
control CANNOT be used under these circumstances.
The transformer must be warmed up until the uid
is liquid enough for the tap change control to be
handled.
a. If the transformer has a no-load tap changer:
i. The no-load voltage tap changers must always
be operated without electrical power, ensuring
the handle is well locked and in its working
position.
ii. Check that the electrical voltage applied
matches the transformer's rated voltage. In the
case of anomaly, contact the Ormazabal.
iii. If, after commissioning the transformer, it is
necessary to perform an adjustment, follow the
safety instructions specified in section 6.1 of this
general instructions manual.
d. If the transformer has an on-load tap changer (OLTC),
follow the specific instructions for this changer as
supplied with the transformer.

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Start up
General Instructions
transforma.plur: Transformers with corrugated tank
and submerged in dielectric liquid from 3150 kVA
5. Keep the transformer supplied with no-load for at least
12 hours, checking that there are no anomalies in any of
the transformer instruments.
6. Progressively apply the load until the operating power
is achieved, while ensuring that the transformer
temperature does not go over 105 °C. In the case of
renewable generation transformers, connect to the
generation source in low generation conditions and let
it increase naturally.
Risk of death caused by electric shock and of
irreversible damage to the transformer or to the
electrical installation.
• Before handling the installation, exactly follow the
instructions of Section 6.1 of this general instructions
document.
• Do not operate the tap changer with no load with
electrical power applied to the transformer.