WEG GRTA-2D User manual

Motors | Automation | Energy | Transmission & Distribution | Coatings
Automatic Voltage Regulator
Regulador Automático de Tensión
Regulador Automático de Tensão
GRTA-2D
Installation, Operation and Maintenance Manual
Manual de Instalación, Operación y Mantenimiento
Manual de Instalação, Operação e Manutenção

Installation, Operation and Maintenance Manual
Manual de Instalación, Operación y Mantenimiento
Manual de Instalação, Operação e Manutenção
Document # / Nº do documento: MGML07-00141
Models / Modelos: GRTA-2D
Language / Idioma: English / Español / Português
Revision / Revisión / Revisão: 08
December / Diciembre / Dezembro, 2022

GENERAL INDEX / ÍNDICE GENERAL / ÍNDICE GERAL
Installation, Operation and Maintenance Manual
Pages 7 - 17
Manual de Instalación, Operación y Mantenimiento
Páginas 18 - 29
Manual de Instalação, Operação e Manutenção
Páginas 30 - 40
Português Español English
Apendix A / Apéndice A / Apêndice A
Pages / Páginas 41 - 47

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Automatic Voltage Regulator –GRTA-2D l 7
FOREWORD
This manual may in no way be reproduced, filed, or transmitted through any type of media, whether
it be electronically, by printing, phonographically or any other audiovisual means without prior
consent from WEG. Infringement is subject to prosecution under the law.
Due to the continuous improvement of WEG products, the present manual may be modified and/or
updated without prior notice which may result in new revisions of the installation and maintenance
manuals for the same product.
WEG reserves itself the right not to update automatically the information included in this manual.
However, customers may at any time request any updated version of the manual, which will be
supplied to them free of charge.
If requested, WEG can supply an extra copy of this manual. The customer should inform the
equipment serial number and model, when making the request.
ATTENTION
1. It is necessary to follow the procedures contained in this manual for the warranty to be valid.
2. Qualified personnel must execute the alternator installation, operation, and maintenance.
NOTES
1. The total or partial reproduction of the information supplied in this manual is authorized, if reference is
made to its source;
2. If this manual is lost, an electronic PDF file is available from our website www.weg.net or another
printed copy can be requested.

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Automatic Voltage Regulator –GRTA-2D l 9
INDEX
1SAFETY INFORMATION ............................................................................................11
2STORAGE INFORMATION.........................................................................................11
3INTRODUCTION .........................................................................................................11
4TECHNICAL CHARACTERISTICS.............................................................................12
5REGULATOR NAMEPLATE.......................................................................................12
6BLOCK DIAGRAM......................................................................................................13
7TRIMPOTS FUNCTION...............................................................................................13
8TRIMPOTS ADJUSTMENT.........................................................................................13
9OPERATION ...............................................................................................................14
9.1 VOLTAGE REGULATOR..................................................................................................................14
9.2 POWER CIRCUIT CONNECTION ....................................................................................................14
9.3 FIELD FLASHING .............................................................................................................................14
9.4 U/F OPERATION ..............................................................................................................................14
10 CONNECTION DIAGRAMS ........................................................................................15
11 DIMENSIONAL DRAWINGS.......................................................................................15
12 IDENTIFICATION OF CONNECTION TERMINALS ...................................................15
13 DIAGRAM FOR TEST WITHOUT ALTERNATOR......................................................16
14 PROBLEMS, CAUSES AND CORRECTIVE ACTIONS .............................................17
15 PREVENTIVE MAINTENANCE...................................................................................17
16 WARRANTY................................................................................................................17

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Automatic Voltage Regulator –GRTA-2D l 11
1 SAFETY INFORMATION
To guarantee the safety of the operators, the correct installation and proper operation of the equipment, the following precautions
must be taken:
▪Installation and maintenance services should be performed only by qualified personnel, using appropriate equipment;
▪The product instruction manual and specific product documentation must always be consulted before proceeding with its
installation, handling and parameter setting;
▪Adequate precautions should be taken to avoid drops, knocks and/or risks to the operators and the equipment.
Always disconnect the main power supply and wait for the alternator to come to a complete stop, before touching any electrical
component associated with the equipment including the control connectors. Do not touch the input and output connectors since
high voltages may be present even after the power has been switched off and keep them isolated from the rest of the main command
circuit of the alternator.
2 STORAGE INFORMATION
If the alternator needs to be stored for a brief period before its installation and/or start-up, the following measures should be taken:
▪The regulator must remain in its original package or in a similar package which provides the same safety conditions against
mechanical damages, excessive temperature, and humidity to avoid rusting of contacts and metallic parts, damages to integrated
circuits or any other damage arising from improper storage;
▪Properly packaged, the regulator must be kept in a dry and well-ventilated area away from direct sunlight, rain, wind, and other
adverse weather conditions to ensure the preservation of its operational functions.
Failure to comply with the above-mentioned recommendations could exempt the supplier of the equipment from any responsibilities
and liabilities from any resulting damages as well as voiding the warranty on the equipment or damaged part.
3 INTRODUCTION
The GRTA-2D automatic analog voltage regulators are compact while featuring high reliability and low cost. They were designed
with state-of-the-art technology for voltage regulation of brushless synchronous alternators.
Their control and regulation circuits use semiconductors and integrated circuits duly evaluated following the most demanding quality
requirements. Mechanical components for field flashing are not required, and its system is completely solid state and encapsulated
in epoxy resin suitable for maritime environments and able to withstand vibrations of up to 30 mm/s. It is fitted with internal voltage
adjustment by trimpot and external by potentiometer allowing an alternator voltage adjustment.
The PID control system is adjusted with two trimpots that adjust the proportional gain and the integral gain allowing a wide
adjustment range while allowing operation of the regulator with several types of alternators, and with a high number of dynamic
characteristics. The under-frequency protection set point is automatic, and the nominal operating frequency can be set to 50 Hz or
60 Hz by jumper.

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12 l Automatic Voltage Regulator –GRTA-2D
4 TECHNICAL CHARACTERISTICS
Model
Characteristics
GRTA-2D
Nominal operating current
7A
Peak Current (10sec)
10A
Analog input adjustable
±3V or ±5V or ±10V (±15%Vsen)
Droop adjustment for parallel operation
No
Sensing Input
160-300 Vac or 320-600 Vac (Vsen)
Power supply
160-300 Vac (1or 2)
Rectifier gain ratio
0,45
Output voltage¹
72-135 Vdc
Field resistance @ 20ºC
6 up to 50Ω
Static regulation
0,5%
Adjustable dynamic response
8 up to 500ms
Operating frequency
50 Hz or 60Hz
Under Frequency protection (U/F)
Automatic (fixed)
Sensing Voltage Fault Protection
Automatic
Internal voltage adjustment
Adjustable via trimpot, for the complete range of Voltage
Operating Temperature
-40° to +60ºC
EMI suppression
EMI Filter
Approximate weight
285 g ±5%
Table 4.1: Technical characteristics
5 REGULATOR NAMEPLATE
The example above shows the main characteristics to be followed before installation.
NOTE
The identification nameplate is attached to the bottom of the regulator frame.
¹for an input voltage of 170 Vac, the maximum output voltage obtained is 72 Vdc.
For 300 Vac of input voltage, the output voltage obtained is 135 Vdc, that is, the maximum dc output voltage is equal to 0.45 x the
ac voltage input.
Figure 5.1: Regulator Nameplate
Operating Frequency
Model
Power Supply
Excitation Voltage
Rated Current
Sensing Voltage

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Automatic Voltage Regulator –GRTA-2D l 13
6 BLOCK DIAGRAM
Figure 6.1: Block diagram
7 TRIMPOTS FUNCTION
Vad: Voltage adjustment
StbPI: Stability –Proportional and Integer.
StbD: Stability - Derivative.
8 TRIMPOTS ADJUSTMENT
Vad: Rotating CW, voltage increases.
StbPI: Rotating CW, dynamic response will be slower.
StbD: Rotating CW, dynamic response will be slower.
Power stage
G
U/F
DROOP
+
+
-
+
Analog input
±3 or ±5 or ±10 Vdc
Reference value
Excitation field
Automatic
field flashing
PID
Sensing

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14 l Automatic Voltage Regulator –GRTA-2D
9 OPERATION
9.1 VOLTAGE REGULATOR
It compares the actual output voltage from the alternator with the theoretical adjusted value through the trimpot of voltage adjustment
P1, plus the external voltage adjustment (if any). The error is processed by the sensing loop whose value determines the thyristor
firing angle which may vary from 0 to 180°, thus controlling the output voltage of the alternator.
9.2 POWER CIRCUIT CONNECTION
The alternator voltage or the auxiliary winding voltage is connected to the terminals 3 and E3/4. This rectified voltage is applied, in
a controlled fashion, to the alternator exciter field.
9.3 FIELD FLASHING
Generation begins through the residual voltage of the alternator. Once the voltage has reached about 10% of the nominal voltage,
the regulator controls the alternator voltage causing it to rise through the initial ramp in approximately 3 seconds. When the alternator
reaches its nominal value, the PID control loop will maintain the alternator output voltage constant within the adjusted value.
9.4 U/F OPERATION
This operation is determined at jumper of selection of operation frequency., following the logic at the membrane and the instructions
below:
▪Hz 60 = 60 Hz
▪Hz 50 = 50 Hz
The adjustment of operation is automatic made by the voltage regulator.
Figure 9.1: U/F operation
Output voltage (Vac)
Frequency (Hz)
Output voltage (Vac)
Frequency (Hz)
45
U
n
U/f
50
54
U
n
U/f
60

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Automatic Voltage Regulator –GRTA-2D l 15
10 CONNECTION DIAGRAMS
The connection diagrams are attached (Appendix A) and must be followed according to the electrical connections of alternator that
is represented in this document. For different internal connections of alternator from the representation below, consider the
connection from alternator manufacturer. The connection pins are showed below:
Figure10.1: Connection pins’ identification
ATTENTION
1. Before connecting the regulator to the alternator, check installation manual and the nominal reference
voltage;
2. If the reference voltage is not equal to the alternator output voltage, do not make the connections
without first contacting the service department.
11 DIMENSIONAL DRAWINGS
Figure 11.1: Dimensional (mm)
12 IDENTIFICATION OF CONNECTION TERMINALS
E1: Sensing Voltage (160 up to 300Vac).
E2: Voltage (320 up to 600Vca).
3: Power supply.
E3/4: Power supply.
F+, F-: Connection for alternator field.
Hz: Jumper for selecting the operating frequency 50/60 Hz (Hz 50 = 50 Hz / Hz 60 = 60 Hz).
A+, A-:Analog input for adjustment of voltage.
Aux: Selection of analog input range (±3Vdc/±5Vdc/±10Vdc).
Overview
Sideview

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16 l Automatic Voltage Regulator –GRTA-2D
13 DIAGRAM FOR TEST WITHOUT ALTERNATOR
Below is the diagram for regulator connection on the bench where the equipment operation may be verified before connection to
the alternator.
Material required:
- 1 Small screwdriver;
- 1 Incandescent lamp;
- 1 Lamp socket;
- 1 Bipolar breaker (5A recommended);
- 1 Extension cable;
- 1 Plug 220Vac.
NOTE
1. After performance of such steps as per the procedure the equipment must be sent for evaluation by WEG
technical support.
1º. Assemble the circuit according to the diagram in figure 13.1;
2º With small screwdriver, turn trimpots Vad counterclockwise until the end of stroke;
3º Turn on circuit breaker:
4º Turn slightly the trimpot Vad clockwise (the lamp must shine after certain position of trimpot)
5º With lamp on, turn slightly the trimpot Vad counterclockwise (after certain position of trimpot, the lamp must turn off);
6º Turn off the circuit breaker.
Figure 13.1: Test diagram
/5A
/1A

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Automatic Voltage Regulator –GRTA-2D l 17
14 PROBLEMS, CAUSES AND CORRECTIVE ACTIONS
Table 14.1
Problems
Causes
Corrective Actions
Generated voltage decreases when load is
applied, and it does not return.
▪Dropping speed of the driving machine;
▪Under frequency protection engaged.
▪Correct speed regulation.
▪Adjust Under frequency protection by rotating
trimpot P5 clockwise (CW).
Alternator voltage does not increase.
▪Residual voltage excessively low
▪Terminals F (+) and F (-) are inverted.
▪Sensing voltage is under pattern or not
connected.
▪With the regulator switched- on, use external
battery (12Vdc) (*) to force excitation.
▪Invert F (+) and F (-).
▪Connect your sensing voltage to the
compatible pin to the nominal voltage from
your generator following the instructions
contained in this manual.
Generated voltage oscillates at no load.
▪Dynamic not well adjusted.
▪Alternator excitation voltage excessively
low.
▪Adjust StbPI and StbD trimpots;
▪Check if the U/F limiter is working, if it is,
increase the machine speed.
▪Check the polarity of the F+ and F-
connections in relation to the generator field
cables;
▪Insert 10Ω/100W resistor in series with field.
Voltage oscillates at a specific load point.
▪Third harmonic of the auxiliary coil is
high.
▪Eliminate auxiliary coil and proceed with the
connections according to the diagrams of
pages 43, 44 or 45.
Voltage surges.
▪Lack of sensing.
▪Faulty electronic circuit.
▪Sensing voltage incompatible with
regulator.
▪Check if alternator phases are present in the
sensing.
▪If the regulator is encapsulated, replace it.
(*) For battery diesel generator where the alternator neutral is grounded battery should always be used independently.
15 PREVENTIVE MAINTENANCE
Periodical inspections of the equipment are required to ensure they are clean, dust and moisture free. It is essential that all terminal
and connections are kept free from corrosion.
16 WARRANTY
See Installation and Maintenance Manual for WEG Alternators.
WEG Group - Energy Business Unit
Jaraguá do Sul - SC - Brazil
Telefono: 55 (47) 3276-4000
[email protected]
www.weg.net

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Regulador Automático de Tensión –GRTA-2D l 19
PREFACIO
Esta publicación no podrá en ninguna hipótesis ser reproducida, almacenada o transmitida a través de algún
tipo de medio, sea electrónico, impreso, fonográfico o cualquier otro posible medio audiovisual, sin la
autorización previa de WEG Industrias S.A. Los infractores estarán sujetos a las penas previstas en la ley.
Esta publicación podrá ser alterada y / o actualizada y podrán resultar en nuevas revisiones de los
manuales de instalación, operación y mantenimiento, teniendo en vista el continuo perfeccionamiento de los
productos WEG.
La WEG se reserva el derecho de la no-obligatoriedad de actualización automática de las informaciones
contenidas en estas nuevas revisiones. No obstante, eso, y en cualquier momento el cliente podrá solicitar
material actualizado que le será provisto sin cargos resultantes.
En caso de pérdida del manual de instrucciones, la WEG podrá proveer ejemplar separado y caso fuera
necesario, informaciones adicionáis sobre el producto. Las solicitaciones podrán ser atendidas, siempre que
sea informado el número de serie y modelo del equipo.
ATENCIÓN
1. Es imprescindible seguir los procedimientos contenidos en este manual para que la garantía tenga
validez;
2. Los procedimientos de instalación, operación y mantenimiento del alternador deberán hacerse por
personal calificado.
NOTAS
1. La reproducción de las informaciones de este manual, total o en partes, se permite desde que la
fuente sea citada;
2. Si se extraviar este manual, el archivo electrónico en formato PDF está disponible en el sitio
www.weg.net o podrá ser solicitada otra copia impresa.