Areva MVAJ05 User manual

Types MVAJ05, 10, 20
Tripping and Control Relays
Service Manual
R8141B

HANDLING OF ELECTRONIC EQUIPMENT
A person’s normal movements can easily generate electrostatic potentials of several
thousand volts. Discharge of these voltages into semiconductor devices when
handling circuits can cause serious damage, which often may not be immediately
apparent but the reliability of the circuit will have been reduced.
The electronic circuits of AREVA T&D products are immune to the relevant levels of
electrostatic discharge when housed in their cases. Do not expose them to the risk of
damage by withdrawing modules unnecessarily.
Each module incorporates the highest practicable protection for its semiconductor
devices. However, if it becomes necessary to withdraw a module, the following
precautions should be taken to preserve the high reliability and long life for which the
equipment has been designed and manufactured.
1. Before removing a module, ensure that you are a same electrostatic potential
as the equipment by touching the case.
2. Handle the module by its front-plate, frame, or edges of the printed circuit
board. Avoid touching the electronic components, printed circuit track or
connectors.
3. Do not pass the module to any person without first ensuring that you are both
at the same electrostatic potential. Shaking hands achieves equipotential.
4. Place the module on an antistatic surface, or on a conducting surface which is
at the same potential as yourself.
5. Store or transport the module in a conductive bag.
More information on safe working procedures for all electronic equipment can be
found in BS5783 and IEC 60147-0F.
If you are making measurements on the internal electronic circuitry of an equipment
in service, it is preferable that you are earthed to the case with a conductive wrist
strap.
Wrist straps should have a resistance to ground between 500k – 10M ohms. If a
wrist strap is not available you should maintain regular contact with the case to
prevent the build up of static. Instrumentation which may be used for making
measurements should be earthed to the case whenever possible.
AREVA T&D strongly recommends that detailed investigations on the electronic
circuitry, or modification work, should be carried out in a Special Handling Area such
as described in BS5783 or IEC 60147-0F.

SAFETY SECTION
1. INSTALLATION 11
1.1 General 11
1.2 Receipt 11
1.3 Unpacking 11
1.4 Storage 11
1.5 Installation 12
2. COMMISSIONING 12
2.1 Commissioning preliminaries 12
2.1.1 Electrostatic discharge (ESD) 12
2.1.2 Inspection 12
2.1.3 Wiring 12
2.1.4 External links 12
2.2 Preliminary checks 13
2.3 Insulation tests 14
2.4 Operate/reset operation 14
2.4.1 Self, hand, electrical and hand/electrical reset 14
2.4.2 Self-reset 2.5s delayed reset 15
2.5 Restoration of wiring 15
2.6 Problem analysis 15
3. MAINTENANCE 15
4. MECHANICAL SETTINGS 15
4.1 General 15
4.2 Cleaning contacts 16
4.3 Contact settings 16
4.4 Settings 16
4.4.1 Relay types MVAJ05 16
4.4.2 Relay types MVAJ10, MVAJ20 17
5. SPARES 17
5.1 Repairs 17
6. CONNECTION DIAGRAMS 18
7. COMMISSIONING TEST RECORD 33
REPAIR FORM 35

Figure 1 Typical application diagram MVAJ051 19
Figure 2 Typical application diagram MVAJ053 20
Figure 3 Typical application diagram MVAJ054 21
Figure 4 Typical application diagram MVAJ055 22
Figure 5 Typical application diagram MVAJ101 23
Figure 6 Typical application diagram MVAJ102 24
Figure 7 Typical application diagram MVAJ103 25
Figure 8 Typical application diagram MVAJ104 26
Figure 9 Typical application diagram MVAJ105 27
Figure 10 Typical application diagram MVAJ201 28
Figure 11 Typical application diagram MVAJ202 29
Figure 12 Typical application diagram MVAJ203 30
Figure 13 Typical application diagram MVAJ204 31
Figure 14 Typical application diagram MVAJ205 32

CONTENT
1. SAFETY SECTION 3
1.1 Health and safety 3
1.2 Explanation of symbols and labels 3
2. INSTALLING, COMMISSIONING AND SERVICING 3
3. EQUIPMENT OPERATING CONDITIONS 4
3.1 Current transformer circuits 4
3.2 External resistors 4
3.3 Battery replacement 4
3.4 Insulation and dielectric strength testing 4
3.5 Insertion of modules and pcb cards 4
3.6 Fibre optic communication 5
4. OLDER PRODUCTS 5
5. DECOMMISSIONING AND DISPOSAL 5
6. TECHNICAL SPECIFICATIONS 6

1. SAFETY SECTION
This Safety Section should be read before commencing any work on the
equipment.
1.1 Health and safety
The information in the Safety Section of the product documentation is intended to
ensure that products are properly installed and handled in order to maintain them in
a safe condition. It is assumed that everyone who will be associated with the
equipment will be familiar with the contents of the Safety Section.
1.2 Explanation of symbols and labels
The meaning of symbols and labels may be used on the equipment or in the product
documentation, is given below.
Caution: refer to product documentation Caution: risk of electric shock
Protective/safety *earth terminal Functional *earth terminal
Note: This symbol may also be
used for a protective/safety earth
terminal if that terminal is part of a
terminal block or sub-assembly
e.g. power supply.
*NOTE: THE TERM EARTH USED THROUGHOUT THE PRODUCT DOCUMENTATION IS THE
DIRECT EQUIVALENT OF THE NORTH AMERICAN TERM GROUND.
2. INSTALLING, COMMISSIONING AND SERVICING
Equipment connections
Personnel undertaking installation, commissioning or servicing work on this
equipment should be aware of the correct working procedures to ensure safety. The
product documentation should be consulted before installing, commissioning or
servicing the equipment.
Terminals exposed during installation, commissioning and maintenance may present
a hazardous voltage unless the equipment is electrically isolated.
If there is unlocked access to the rear of the equipment, care should be taken by all
personnel to avoid electrical shock or energy hazards.

Voltage and current connections should be made using insulated crimp terminations
to ensure that terminal block insulation requirements are maintained for safety. To
ensure that wires are correctly terminated, the correct crimp terminal and tool for the
wire size should be used.
Before energising the equipment it must be earthed using the protective earth
terminal, or the appropriate termination of the supply plug in the case of plug
connected equipment. Omitting or disconnecting the equipment earth may cause a
safety hazard.
The recommended minimum earth wire size is 2.5mm2, unless otherwise stated in the
technical data section of the product documentation.
Before energising the equipment, the following should be checked:
− Voltage rating and polarity;
− CT circuit rating and integrity of connections;
− Protective fuse rating;
− Integrity of earth connection (where applicable)
− Remove front plate plastic film protection
− Remove insulating strip from battery compartment
3. EQUIPMENT OPERATING CONDITIONS
The equipment should be operated within the specified electrical and environmental
limits.
3.1 Current transformer circuits
Do not open the secondary circuit of a live CT since the high level voltage produced
may be lethal to personnel and could damage insulation.
3.2 External resistors
Where external resistors are fitted to relays, these may present a risk of electric shock
or burns, if touched.
3.3 Battery replacement
Where internal batteries are fitted they should be replaced with the recommended
type and be installed with the correct polarity, to avoid possible damage to the
equipment.
3.4 Insulation and dielectric strength testing
Insulation testing may leave capacitors charged up to a hazardous voltage. At the
end of each part of the test, the voltage should be gradually reduced to zero, to
discharge capacitors, before the test leads are disconnected.
3.5 Insertion of modules and pcb cards
These must not be inserted into or withdrawn from equipment whist it is energised
since this may result in damage.

3.6 Fibre optic communication
Where fibre optic communication devices are fitted, these should not be viewed
directly. Optical power meters should be used to determine the operation or signal
level of the device.
4. OLDER PRODUCTS
Electrical adjustments
Equipments which require direct physical adjustments to their operating mechanism
to change current or voltage settings, should have the electrical power removed
before making the change, to avoid any risk of electrical shock.
Mechanical adjustments
The electrical power to the relay contacts should be removed before checking any
mechanical settings, to avoid any risk of electric shock.
Draw out case relays
Removal of the cover on equipment incorporating electromechanical operating
elements, may expose hazardous live parts such as relay contacts.
Insertion and withdrawal of extender cards
When using an extender card, this should not be inserted or withdrawn from the
equipment whilst it is energised. This is to avoid possible shock or damage hazards.
Hazardous live voltages may be accessible on the extender card.
Insertion and withdrawal of heavy current test plugs
When using a heavy current test plug, CT shorting links must be in place before
insertion or removal, to avoid potentially lethal voltages.
5. DECOMMISSIONING AND DISPOSAL
Decommissioning: The auxiliary supply circuit in the relay may include capacitors
across the supply or to earth. To avoid electric shock or energy
hazards, after completely isolating the supplies to the relay (both
poles of any dc supply), the capacitors should be safely
discharged via the external terminals prior to decommissioning.
Disposal: It is recommended that incineration and disposal to water
courses is avoided. The product should be disposed of in a safe
manner. Any products containing batteries should have them
removed before disposal, taking precautions to avoid short
circuits. Particular regulations within the country of operation,
may apply to the disposal of lithium batteries.

6. TECHNICAL SPECIFICATIONS
Protective fuse rating
The recommended maximum rating of the external protective fuse for this equipment
is 16A, Red Spot type or equivalent, unless otherwise stated in the technical data
section of the product documentation.
Insulation class: IEC 601010-1 : 1990/A2 : 2001
Class I
EN 61010-1: 2001
Class I
This equipment requires a
protective (safety) earth
connection to ensure user
safety.
Insulation
Category
(Overvoltage):
IEC 601010-1 : 1990/A2 : 1995
Category III
EN 61010-1: 2001
Category III
Distribution level, fixed
insulation. Equipment in this
category is qualification tested
at 5kV peak, 1.2/50µs,
500Ω, 0.5J, between all supply
circuits and earth and also
between independent circuits.
Environment: IEC 601010-1 : 1990/A2 : 1995
Pollution degree 2
EN 61010-1: 2001
Pollution degree 2
Compliance is demonstrated
by reference to generic safety
standards.
Product Safety: 72/23/EEC
EN 61010-1: 2001
EN 60950-1: 2002
Compliance with the European
Commission Low Voltage
Directive.
Compliance is demonstrated
by reference to generic safety
standards.

Page 11
Section 1. INSTALLATION
1.1 General
Protective relays, although generally of robust construction, require careful
treatment prior to installation and a wise selection of site. By observing a few
simple rules the possibility of premature failure is eliminated and a high degree of
performance can be expected.
The safety section should be read before any work takes place and should be
referred to throughout. Special care should be taken to adhere to suitable electro-
static discharge precautions.
1.2 Receipt
The relays are either despatched individually or as part of a panel/rack mounted
assembly in cartons specifically designed to protect them from damage.
Relays should be examined immediately they are received to ensure that no
damage has been sustained in transit. If damage due to rough handling is evident,
a claim should be made to the transport company concerned immediately and
AREVA T&D should be promptly notified. Relays which are supplied unmounted and
not intended for immediate installation should be returned to their protective polythene
bags.
1.3 Unpacking
Care must be taken when unpacking and installing the relays so that none of the
parts are damaged or their settings altered and must only be handled by skilled
persons.
Relays should be examined for any wedges, clamps, or rubber bands necessary to
secure moving parts to prevent damage during transit and these should be
removed after installation and before commissioning.
Relays which have been removed from their cases should not be left in situations
where they are exposed to dust or damp. This particularly applies to installations
which are being carried out at the same time as construction work.
1.4 Storage
If relays are not installed immediately upon receipt they should be stored in a place
free from dust and moisture in their original cartons and where de-humidifier bags
have been included in the packing they should be retained. The action of the
de-humidifier crystals will be impaired if the bag has been exposed to ambient
conditions and may be restored by gently heating the bag for about an hour, prior
to replacing it in the carton.
Dust which collects on a carton may, on subsequent unpacking, find its way into
the relay; in damp conditions the carton and packing may become impregnated
with moisture and the de-humidifying agent will lose its efficiency.
The storage temperature range is –40°C to +70°C.

Page 12
1.5 Installation
The installation should be clean, dry and reasonably free from dust and excessive
vibration. The site should preferably be well illuminated to facilitate inspection.
An outline diagram is normally supplied showing panel cut-outs and hole centres.
For individually mounted relays these dimensions will also be found in publication
R6141.
Publication R7012, Parts Catalogue and Assembly Instructions, will be useful when
individual relays are to be assembled as a composite rack or panel mounted
assembly.
Publication R6001 is a leaflet on the modular integrated drawout system of
protective relays.
Publication R6014 is a list of recommended suppliers for the pre-insulated
connectors.
Section 2. COMMISSIONING
2.1 Commissioning preliminaries
2.1.1 Electrostatic discharge (ESD)
The relay uses components which are sensitive to electrostatic discharges. When
handling the withdrawn module, care should be taken to avoid contact with
components and electrical connections. When removed from its case for storage
the module should be placed in an electrically conducting anti-static bag.
2.1.2 Inspection
Carefully examine the module and case to see that no damage has occurred
during transit.
Check that the relay serial number on the module, case and cover are identical,
and also check that the rating information is correct for the system.
2.1.3 Wiring
Warning
Exposed terminals may present a hazardous voltage unless
equipment is electrically isolated.
Check that the external wiring is correct to the relevant relay diagram and/or
scheme diagram. It is especially important that DC supplies are wired with the
correct polarity. The relay external connection diagram number is given on the
rating label inside the case.
2.1.4 External links
There are two external links as detailed in tables 1 and 2.
All trip relays are supplied as high burden. With the exception of MVAJ102, 202,
they may be converted to low burden by removing the link between case terminals
22 and 24.

Page 13
Relay type Feature Link in Link out
MVAJ 051, 053, 054, 055 Burden High Low
Cut-off Instantaneous Instantaneous
MVAJ 101, 103, 104, 105 Burden High Low
201, 203, 204, 205 Cut-off 40-60ms time delayed Instantaneous
MVAJ102, 202 Link not necessary - configured as high burden models
Note: At the point at which the relay cut-off occurs the current drawn by the relay
is either reduced to an economised level or is removed entirely (ie. zero
watt cut-off state).
Table 1: Configuration of high/low burden link (terminals 22 to 24)
A second link is supplied fitted to selected 10 and 20 contact relays as detailed in
Table 2. This link, connected between case terminals 21 and 23 enables a reset
inhibitor feature to be introduced into the circuit of 10 and 20 contact electrical
reset relays, ensuring that the reset circuit is disabled when the operate circuit is
energised.
On relay types 104, 105, 204 and 205 this link may be removed if this feature is
not required.
NB. This link must remain fitted to MVAJ101 and 201 relays to enable the
economising circuit.
Relay type Feature Link in Link out
MVAJ051, 053, 054, 055, Link not available
102, 202
MVAJ101, 201 Link fitted (relay cut-off to economised state)
MVAJ103, 203 Link not available (relay cut-off to zero watts)
MVAJ104, 105, 204, 205 Cut-off state economised zero watts
reset inhibitor active disabled
Table 2: Configuration of economising/reset inhibit link (terminals 21 to 23)
2.2 Preliminary checks
Before leaving the factory all relays are accurately adjusted, tested and carefully
packed. There should be no need for any re-adjustment on commissioning.
Moving parts are held in position during transit by rubber bands and packing.
These should be removed carefully.
2.2.1 To gain access to the relay first loosen the captive cover screws, then carefully
remove the cover from the case.
The module can then be removed from the case by grasping the handles at the top
and bottom of the front plate and pulling forwards.
Care must be taken to ensure that mechanical settings of the element are not
disturbed.

Page 14
2.2.2 Carefully remove the rubber band securing the flag mechanism.
2.2.3 Check that the bottom end of the contact operating card has not been dislodged
from the slot in the armature extension.
2.2.4 Check that all push-on connections to the PCB are secure.
Check that all the push-on connections to the back of the contacts are secure.
Check that all the push-on connections to terminal block are secure.
2.2.5 Carefully actuate the armature of each unit in turn with a small screwdriver/probe.
On units fitted with hand reset flag indicators, check that the flag is free to fall
before, or just as, any make contacts close.
2.2.6 Check that the serial number in the cover and the relay case match that of the
module. Replace the module in the case and refit the cover. Make sure that the
reset mechanism in the cover is correctly located with respect to the relay element
and that the flag (or mechanism) can be reset.
Check that the armature(s) are in the reset position by pressing the appropriate
reset buttons.
2.3 Insulation tests
The relay and its associated wiring may be insulation tested between:
– all electrically isolated circuits
– all circuits and earth
An electronic or brushless insulation tester should be used giving a dc voltage not
exceeding 1000V. Accessible terminals of the same circuit should first be strapped
together. Deliberate circuit earthing links removed for the tests must subsequently
be replaced.
2.4 Operate/reset operation
Warning
Exposed terminals may present a hazardous voltage unless
equipment is electrically isolated.
2.4.1 Self, hand, electrical and hand/electrical reset
The operate circuit is terminated to case terminals 27(+), 28(-). The electrical reset
circuit is terminated to case terminals 25(+), 26(-). Disconnect external wiring from
these terminals to allow application of the test supply.
With the relay reset check the continuity of the closed contacts (shown as break
contacts on the drawing).
Check operation of operate circuit and the electrical reset circuit (if applicable) by
energising the relay with 60% of the lower nominal supply voltage.
The relays should switch cleanly with one movement.
Check the operating time of the relay at 100% lower nominal supply voltage and
check the continuity of the closed contacts (shown as make contacts on the
drawing).

Page 15
2.4.2 Self-reset 2.5s delayed reset
The operate circuit is terminated to case terminals 25(+), 27(+), 28(-). Disconnect
external wiring from these terminals to allow application of the test supply.
With the relay reset check the continuity of the closed contacts (shown as break
contacts on the drawing).
Check operation of operate circuit by energising the relay with 60% of the lower
nominal supply voltage.
The relays should switch cleanly with one movement.
Check the operating time of the relay at 100% lower nominal supply voltage and
check the continuity of the closed contacts (shown as make contacts on the
drawing).
Check the delayed reset time by energising the relay with full rated supply volts to
case terminations 25(+), 27(+), 28(-), then remove energisation from the case
termination 27(+). Time the closure of a normally closed contact from this point in
time. The reset time shall be between 2 - 2.8s.
2.5 Restoration of wiring
Restore any external wiring connections that may have been disturbed during the
above tests.
2.6 Problem analysis
Repeat Section 2.2 with particular attention to the connection of external links.
If the relay is found to be faulty it should be returned to AREVA T&D for repair and
recalibration. There are no user serviceable parts inside.
Section 3. MAINTENANCE
Periodic maintenance is not necessary, however routine testing should be carried
out the meet the customer requirements.
Check the relay for operation at 60% lower nominal supply voltage and for
contact wear. If required, the mechanical settings may be checked against those
shown in Section 4.
Section 4. MECHANICAL SETTINGS
4.1 General
Contacts are set at the factory and should not require adjustment.
If contacts show signs of contamination during maintenance it may be necessary to
clean contacts and check settings.
Contacts must be checked by qualified personnel only to
ensure that settings are not disturbed.
The safety section should be read before attempting any adjustments.

Page 16
4.2 Cleaning contacts
Contacts should be cleaned with the burnishing tool, supplied in relay tool kits.
On no account should cleaning fluids, knives, files or abrasive materials be used.
4.3 Contact settings
Armature gap measurements should be made with the top of the feeler gauge level
with the centre line of the core.
Contact pressures are measured with a gramme gauge at the contact tips.
In general contact gaps and follow through are defined by quoting an armature
gap at which the tips should be just closed or just open. Follow through should be
measured at the centre of the armature. Some mechanically operated contact gaps
must be measured directly with feeler gauges at the contact tips.
The relay contact state is always defined with the relay in the reset position unless
otherwise specified on the appropriate circuit diagram.
Symbols used on diagrams
Contact type Normal duty
Make (normally open) M
Break (normally closed) B
4.4 Settings
Settings should be within those specified in the following tables.
4.4.1 Relay types MVAJ05
Standard armature gap 1.5 to 1.25 mm
Make Follow through – just closed 0.5 mm
– just open 0.6 mm
Force to make 25 to 30 grammes
Break Contact gaps 1.25 to 1.5 mm
Force to break 25 to 30 grammes
Break Cut off contact (top left-hand viewed from front)
Force to break 25 to 30 grammes
Contact gap 0.2 to 0.5 mm
(measured at armature)

Page 17
4.4.2 Relay types MVAJ10, MVAJ20
Standard Following Units
flag flag
Standard armature gap 1.5 to 1.4 1.5 to 1.25 mm
Make Follow through – just closed 0.5 0.5 mm
– just open 0.6 0.6 mm
Force to make 26 to 29 20 to 25 grammes
Force to make 30 to 35 25 to 30 grammes
(when less than 4 make)
Break Contact gaps 1.25 to 1.5 1.25 to 1.5 mm
Force to break 26 to 29 20 to 25 grammes
Break Cut off contact (bottom right-hand viewed from front)
Force to break 25 to 30 20 to 25 grammes
Contact gap measured 0.4 to 0.6 0.4 to 0.6 mm
at the armature centre
Section 5. SPARES
When ordering spares, quote the full relay model number and any component
reference numbers, or briefly describe the part required.
5.1 Repairs
Should the need arise for the equipment to be returned to AREVA T&D for repair, then
the form at the back of this manual should be completed and sent with the equipment
together with a copy of any commissioning test results.

Page 18
Section 6. CONNECTION DIAGRAMS
5 contact versions
01 MVAJ051 01 self reset
01 MVAJ053 01 hand reset
01 MVAJ054 01 electrical reset
01 MVAJ055 01 hand and electrical reset
10 contact versions
01 MVAJ101 01 self reset
01 MVAJ102 01 self reset (2s delayed reset)
01 MVAJ103 01 hand reset
01 MVAJ104 01 electrical reset
01 MVAJ105 01 hand and electrical reset
20 contact versions
01 MVAJ201 01 self reset
01 MVAJ202 01 self reset (2s delayed reset)
01 MVAJ203 01 hand reset
01 MVAJ204 01 electrical reset
01 MVAJ205 01 hand and electrical reset
Where required, any specific diagram may be supplied on request. If the actual
diagram number is not known, please provide the full model number and serial
number. Typical diagrams follow.