GRT7-TH4E/PE

Automatic Voltage Regulator

Installation, Operation and Maintenance Manual

GRT7-TH4E/PE MGEN[07-00018] REV08

Congratulations, you have just purchased a high-quality product, carefully read the
instructions in this manual before installing the equipment. This publication may not under
any circumstances be reproduced, stored, or transmitted through any type of media,
whether electronic, printed, phonographic or any other audiovisual medium, without the
prior authorization of G-MEYER COMPONENTS. Violators will be subject to the penalties
provided for by law.

This publication is subject to changes and/or updates that may result in further revisions
of the installation and operation manuals, with a view to the continuous improvement of
G-MEYER COMPONENTS products. G-MEYER COMPONENTS reserves the right not
to automatically update the information contained in these new revisions. However, at
any time the customer may request updated material that will be provided to him without
any charges arising.

This manual is always provided in printed format with the equipment when purchased.

* In the event of loss of the instruction manual, G-MEYER COMPONENTS may provide a single
copy, and if necessary, additional product information. Requests can be fulfilled if you have informed
the serial number and model of the equipment.

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SAFETY INFORMATION

To ensure the safety of operators, the correct installation of the equipment and its
preservation, the following precautions should be taken:

Only persons trained and authorized by the manufacturer are authorized to install this
equipment because improper intervention by an unqualified person may cause damage
to the equipment and generator;

Instruction manuals and product identification labels should always be observed before
installing, handling, and parameterizing;

Appropriate precautions should be taken against falls, physical shocks and/or risks to the
safety of operators and equipment;

Always disconnect the general power supply and wait for the machine to stop fully before
touching any electrical component associated with the equipment, this also includes the
control connectors. Do not touch the input and output connectors as high voltages may
be present even after disconnection from the power supply and always keep them
isolated from the rest of the main generator control circuit. Check the symbology item of
the screen printing of this manual to perform the disconnection of the equipment;

Observe the warning labels glued to the equipment, "care tension" and "hot surface care";

Failure to observe these instructions may cause shock or burns to the operator and cause
damage to the equipment or generator;

This Equipment meets IEC61010-1.

Do not touch the input and output connectors. And always keep them
isolated from the rest of the panel control circuit, unless otherwise
noted.

Always disconnect the general power supply and wait for the machine
to stop fully touching before any electrical component associated with
the equipment, this also includes the control connectors. Do not open
the equipment cover without proper precautions, as high voltages
may be present even after disconnection from the power supply.

The equipment's electronic cards may have components sensitive to

electrostatic discharges. Do not touch components or connectors
directly. If necessary, touch the grounded metal housing first or use a
suitable grounding bracelet.

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STORAGE INFORMATION

➢ In case of need for storage of the regulator for a brief period prior to its
installation and/or commissioning, the following precautions should be taken:
➢ The Regulator shall be kept in its original packaging or packaging that meets
the same safety conditions against mechanical damage, excessive
temperature, and humidity to prevent oxidation of contacts and metal parts,
damage to integrated circuits;
➢ The properly packaged regulator should be housed in a dry, ventilated place
where the direct incidence of sunlight does not occur, as well as rain, wind, and
other weather, to ensure the maintenance of its functional characteristics;
➢ After the regulator is properly packed and accommodated in such a way that it
does not absorb the vibrations and impacts suffered during transport, it will be
able to be transported by the different existing means.
➢ Failure to comply with the above recommendations may exempt the equipment
supplier from any liability for the resulting damage, as well as the loss of
warranty on the damaged equipment or part.

Failure to comply with the above recommendations may

exempt the equipment supplier from any liability for the
resulting damage, as well as the loss of warranty on the
damaged equipment or part.

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WHERE CAN THE EQUIPMENT BE INSTALLED?

The installation and/or commissioning of the equipment may be conducted at:

➢ Generator connection box;

➢ External panel near the generator;
➢ Any place protected from the environment near the Generator;
➢ This equipment is for internal use;
➢ This equipment cannot be installed in the open. Due to climatic conditions such
as rain and may oxidize its terminals causing the equipment to malfunction and
consequently the malfunction of the generator;
➢ Installation of peripherals such as external pot, keys, circuit breakers should be
installed near or near the equipment and in an easily accessible place;
➢ The installation should be done in a closed metal cabinet (grounded or not) so
that the terminals of the same are inaccessible where there is no opening that allows
access to the equipment and access must be done by means of a tool (Philips key,
screwdriver, etc.), remembering that the terminals the equipment should not be
exposed and the peripherals installed in order to meet the IEC61010-1 standard;
➢ This equipment can be installed in places that may be subject to vibrations, heat,
and electromagnetic interference because it is developed to withstand such adverse
conditions;
➢ The diagrams of connection to the generator vary according to type of generator
considering the voltage of the generator, excitation current, whether the generator is
with or without coil auxiliary, etc. All these diagrams are clearly described in item 5 of
this manual.

Failure to comply with the above recommendations may

exempt the equipment supplier from any liability for the
resulting damage, as well as the loss of warranty on the
damaged equipment or part.

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CONVENTIONS USED IN THE MANUAL

Some conventions regarding font types or formatting were used in this manual to
allow a clear and uncomplicated reading. Below are specified the main conventions
used:

NOTE (uppercase): Typed text. (uppercase/lowercase) – Notes and alerts represent

essential information that must be observed by the operator or supervisor of the
operation.

SUBJECT OF THE page – At the edges of each page the reader can have a quick
reference of the main subject being addressed in it, without having to resort to the
indexes to locate the desired information, just to flip through the manual.

Reference to titles and subtitles – References made to titles and subtitles, used during
the text to refer the reader to another more detailed topic on the subject or where the
reader can obtain the desired information contained in the manual, are written in italic
type. Words or expressions in a language other than the current language will also
be written in italic type.

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SUMMARY
INTRODUCTION ........................................................................................................................... 9
TECHNICAL CHARACTERISTICS .............................................................................................. 10
OPERATION U/F.................................................................................................................... 12
ANALOG INPUT ..................................................................................................................... 13
EXTERNAL POT .................................................................................................................... 13
BLOCK DIAGRAM.................................................................................................................. 14
LINK DIAGRAM FOR PARALLEL OPERATION ..................................................................... 15
INTERNAL LINK DIAGRAM ................................................................................................... 16
CONTROL DIAGRAM ............................................................................................................ 17
PRE-EXCITATION ................................................................................................................. 17
IDENTIFICATION ........................................................................................................................ 18
IDENTIFICATION LABEL ....................................................................................................... 18
ADHESIVE MEMBRANES...................................................................................................... 19
DESCRIPTION OF GENERATOR CONNECTION TERMINALS ............................................ 19
TRIMPOT'S FUNCTION .............................................................................................................. 20
CONNECTION TO GENERATOR ............................................................................................... 21
CONNECTION TO GENERATOR WITH AUXILIARY COIL .................................................... 22
STAR-SERIES CONFIGURATION .................................................................................... 22
STAR-PARALLEL CONFIGURATION ............................................................................... 23
DELTA-SERIES CONFIGURATION .................................................................................. 24
DELTA-PARALLEL CONFIGURATION ............................................................................. 25
CONNECTION WITHOUT AUXILIARY COIL ......................................................................... 26
STAR-SERIES CONNECTION .......................................................................................... 26
STAR-PARALLEL CONNECTION ..................................................................................... 27
DELTA-SERIES CONNECTION ........................................................................................ 28
DELTA-PARALLEL CONNECTION ................................................................................... 29
PARALLEL OPERATION OF TWO OR MORE GENERATORS ............................................. 30
FIRST INSTALLATION OF THE VOLTAGE REGULATOR ......................................................... 32
STEPS FOR CONNECTION .................................................................................................. 32
DISCONNECTION ................................................................................................................. 32
CONNECTION DIAGRAM FOR BENCH TEST ...................................................................... 33
DIMENSIONAL............................................................................................................................ 34

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SYMBOLOGY OF SERIGRAPHY ............................................................................................... 35

FIRST USE ................................................................................................................................. 35
DISCONNECTION ...................................................................................................................... 36
PREVENTIVE MAINTENANCE ................................................................................................... 37
RISK REDUCTION ...................................................................................................................... 38
NOTES TO THE PERSON RESPONSIBLE FOR MAINTENANCE AND INSTALLATION SERVICE
.................................................................................................................................................... 39
WARRANTY TERM ..................................................................................................................... 40
PROBLEMS, CAUSES AND SOLUTIONS .................................................................................. 41

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INTRODUCTION
The GRT7-TH4E/GRT7TH4PE electronic voltage regulators are compact, high-
reliability, low-cost equipment, which has been developed within the highest technology
for voltage regulation in brushless synchronous generators.

Its control and regulation circuit uses semiconductors and integrated circuits evaluated
within the strictest quality standards. It has no mechanical components for priming and
its system is fully static and encapsulated in resin resistant to sea, able to withstand
vibrations of the Generator. It has internal voltage adjustment via trimpot and external via
pot.

Its control system is adjusted through trimpot that adjusts the stability gain, allowing a
wide range of adjustment, which allows operation with the most diverse types of
generators with the most varied dynamics characteristics.

The equipment has a robust control circuit with overflow protection (U/f) supplying
excellent operability.

The intervention point of the U/F protection is adjustable via trimpot, and the rated
operating frequency is configurable to 50 or 60 Hz, and the other protections via jumper.

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TECHNICAL CHARACTERISTICS
The following table indicates the main technical characteristics of the equipment.

GRT7-TH4PE GRT7-TH4E 10A

Features GRT7-TH4E 5A
7A
Rated excitation current 5A 7A 10 A

Forced excitation current for 1 minute 7A 10 12

Glass Fuse (5x20mm) 5A/250V*** 7A/250V*** 10A/250V***

Maximum input power 750VA 1050VA 1350VA

Power consumed ≈13VA

160 to 300Vca
E1 85 to 140Vca
320 to 600Vca
Feedback (Vral)* E2 170 to 280Vca

Adjustable via trimpot, for all range of VRal voltage

Internal voltage adjustment (Vral) variation
External voltage adjustment via pot −30% of VRal for a 5KΩ** pot
Rated operating voltage (power) 220Vca
Rated operating frequency 50/60Hz
Power supply range (Val) 160Vca to 300Vca
Floating feed voltage ±30%

Power operating frequency (Power) 50 or 60Hz

Generator output voltage sub frequency

protection (U/F) 50 or 60Hz
Maximum field voltage (Vc) 36Vcc (for Minimum Val , /135Vcc (for Max Val)
External voltage control Via 5KΩ/3W pot
Power connection Monophase
Feedback connection Monophase
Rectifier gain ratio (Kc) 0,42
Field resistance at 20ºC 6 - 50Ω
Static regulation 0,5%
Adjustable dynamic response 8 - 500ms

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Working ambient temperature −40ºC to +60ºC

Maximum voltage variation operating 1% to ∆50°C
within the specified thermal limits
Maximum relative air humidity 0 - 80%
Degree of pollution 3
Altitude for operation Up to 4000m above sea level
Interference protection EMI Filter
Approximate weight 477g +/- 5%
Dimensions (WxHxD) 32.45x144.5x165

Parallel operation 10% variation ± (PAR/1 - ratio 1A and PAR/5 ratio 5A)
Polystyrene with high-impact nylon additive anti-flame
Base material (V0)
Analog input +/- 9Vcc ± 10% of Vreal
Storage temperature −40ºC/+60ºC
Encapsulation Resin
Vibration 1.5G @ 5~30Hz - 5.0G @ 30~500Hz
Min Voltage and Frequency for Pre- 5V 25Hz
Priming 5V 25Hz

*The feedback voltage (Vral) may show a variation of ±3% for the maximum and minimum
value presented in the manual.

** Check information on External Potentiometer in this manual.

*** Check fuse information in this manual.

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OPERATION U/F
The figure below shows the graph of variation of the voltage of the generator as a function
of the frequency variation. For rated operating frequency, U/f is disabled. In case of
reduced rotation (e.g. : shutdown), the excitation decreases, reducing the output voltage
of the generator. The voltage drop varies depending on the Vad setting.

13
(Vca) Voltage Drop
U/F (Vac) Voltaje…
Tensão Queda U/F

12
11
10
9
8
7
6
5
4
3
2
1
0
100 150 200 250 300 350 400 450 500 550 600
Vad (Vca / Vac / Vca)
Figure 1 U/F fall

The mode of operation is determined by the P5 trimpot, the JHz jumper , and associated
components. The Hz jumper determines the operating frequency between 50Hz and
60Hz. Trimpot P5 determines the actuation point of U/F mode, which can be from the
rated frequency (Fn) to 1/3 Fn, whose factory-adjusted value is 10% below the Fn. For
Operation at 60Hz is adjusted at approximately 54Hz and for operation at 50Hz is
adjusted to approximately 45Hz, whose value can be changed according to the need of
each application.

Figure 2 Protection actuation point U/f

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ANALOG INPUT
The analog input circuit provides a variation in the voltage reference of the generator with
a variation from -9Vcc to +9Vcc. This input has high impedance. The maximum and
minimum value of the adjustment can be found in the "Technical Characteristics" table.

EXTERNAL POT
Pot terminal 6 is common with the E3/4 terminal that will be connected to a generator
phase or neutral. Therefore, care should be taken with the isolation of the pot cables
(terminal 6 and 7) avoiding the contact of these cables with other metal parts
causing short or electric shocks.

The external pot only lowers the voltage set in Val, so when using the pot, the voltage
should be adjusted in the P1-Vad trimpot with the pot set at half resistance (e.g. 2.5KΩ
for a 5KΩ pot). To use the external pot, the jumper that releases the use of it must be
removed.

In the absence of the jumper that releases the use of the pot, the regulator will not have
voltage control by the P1-Vad trimpot.

NOTE: Only manage the jumper if the regulator is off.

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BLOCK DIAGRAM

Figure 3 Block Diagram

The operation is based on the comparison of the effective value of the feedback voltage
with the voltage reference, set by thesum of the Vad trimpot with the external trimpot.
The comparison between the adjusted voltage value and the read generates an error
which is processed by the PID mesh cujthe output determines the trigger angle of the
thyristor which can range from 0 to 180°, thus controlling the output voltage of the
generator. With zero degree of fire there is zero volts at the rectifier output, and with 180-
degree firing, you have the maximum output given by the half-wave rectifier.
The beginning of generation takes place through the residual voltage of the generator.
After reaching approximately 10% of the rated, the regulator controls the voltage of the
generator causing it to rise until it reaches the adjusted nominal value in the Vad
trimpot. From this moment on, the control mesh will keep the output voltage of the
generator constant within the adjusted value.

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LINK DIAGRAM FOR PARALLEL OPERATION

The parallel type of connection circuit is used for applications where the objective is that
there is no voltage variation in the machine output and reactive compensation.

Figure 4 Connection diagram

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INTERNAL LINK DIAGRAM

Terminal 3 of the power supply is directly connected to terminal F+ and terminal E3/4
connecting through the thyristor to terminal F-.

Figure 5 Internal connection diagram

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CONTROL DIAGRAM
The control block that is presented in the figure below demonstrates in which the GRT 7-
TH4E/PE fhi built, based on the ST1A, presented by IEEE, applied to systems where the
rectifier is alim entado from the generator output (Type ST –Static Excitation Systems),
either directly by auxiliary coils or Shunt.

Figure 6 Control Diagram

PRE-EXCITATION
If pre-excitation is required in the field, it is recommended to use an isolated DC source
or that is isolated from the regulator terminals. Optionally an insulation transformer
(excitation transformer) can be inserted between terminals 3 and E3/4 with the generator
phases through short protection.
It is also recommended to insert a diode in series with the positive of the source being
used to generate the Pre-excitation avoiding the firing of the regulator when it comes to
controlling the excitation voltage, see the example below.

Figure 7 Pre-Excitation

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IDENTIFICATION

IDENTIFICATION LABEL
The equipment identification label is found on the bottom side of the base and follows
the model of the figure. The label should be observed before the equipment is connected.

Figure 6 Pegasus GRT7-TH4PE Label

Figure 8 GRT7-TH4E Label

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ADHESIVE MEMBRANES
The adhesive membranes are used to identify the components in the stress regulator,
and they can be seen in the figure below.

DESCRIPTION OF GENERATOR CONNECTION TERMINALS

Connector Function
E1 Voltage feedback
E2 Voltage enhancement
S1 TC-S1
S2/5 TC 5A-S2
S2/1 TC 1A-S2
6 e7 External voltage adjustment pot connector (two
terminals)
F+ and F- Connection to the generator excitation field

3 Voltage supply
4/3 Voltage power, and regulator reference

Note: The values of "voltage 1" and "voltage 2" are set by E1 and E2 in the
characteristic table (pg.9)

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TRIMPOT'S FUNCTION
Trimpot Function
Voltage adjustment. Turning clockwise increases the
P1 - Vad
tension.

P4 - Stb1 Stability adjustment. Turning clockwise makes the

response slower.

Stability adjustment. Turning counterclockwise the

P3 - Stb2
response becomes faster.

Droop adjustment. Rotating clockwise increases the

P2 - Drp
compensation range of reactive

U/F limiter. Turning clockwise adjusts the operating

P5 - U/F
frequency of U/F.

Figure 9 Trimpots

Note: Some trimpots are pre-regulated and factory sealed, but if necessary,
adjustments, they can be performed according to the procedures described in this
manual.

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CONNECTION TO GENERATOR

Carefully observe the type of connection of your generator to connect this equipment.
If the equipment is connected incorrectly or differently from that specified in the diagrams
below the equipment may be permanently damaged, as well as the generator in which it
will be connected, and the generator and voltage regulator may burn, compromising the
protections of the equipment, increasing the safety risks (shocks, voltaic arcs, high
temperatures).

ATTENTION
➢ Before connecting the regulator to the generator, check the standard rated
voltage in the installation manual;
➢ The supply voltage must not exceed the specified maximum voltage;
➢ If the reference voltage is not equal to the output voltage of the generator, do
not make the connections without first consulting the technical assistance;
➢ Peripheral items are not provided by G-MEYER;
➢ 10A/250Vca circuit breaker (curve C) to turn the regulator on and off (interrupt
device);
➢ Generator line voltages must conform to the feedback class and the regulator's
power voltage level, depending on the technical characteristics.

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CONNECTION TO GENERATOR WITH AUXILIARY COIL

STAR-SERIES CONFIGURATION
The figure below demonstrates the connection for the generator to operate at
380/440/480 V. Voltage adjustment can be made by Vad trimpot.

Figure 10 Star-series configuration with auxiliary coil

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STAR-PARALLEL CONFIGURATION
The figure below demonstrates the connection for the generator to operate in 220 v.
Voltage adjustment can be made by Vad trimpot.

Figure 11 Star-parallel configuration with auxiliary coil

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DELTA-SERIES CONFIGURATION
The figure below demonstrates the connection for the generator to operate at
380/440/480 V. Adjustment can be made by Vad trimpot.

Figure 12 Delta-series configuration with auxiliary coil

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DELTA-PARALLEL CONFIGURATION
The figure below demonstrates the connection for the generator to operate at 220V.
Voltage adjustment can be made by Vad trimpot.

Figure 13 Delta-parallel configuration with auxiliary coil

1Item not supplied by G-MEYER COMPONENTS, observe relationship specifications
(PAR/1 or PAR/5);
2 If there is no pot connected, jump pins on jumper 6 and 7 (short-circuit);
3 5A/250Vca circuit breaker (curve C) to turn the regulator on and off (interrupt device)

* Generator line voltages, depending on the feedback class and the regulator's power
voltage level, depending on the technical characteristics.

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CONNECTION WITHOUT AUXILIARY COIL

STAR-SERIES CONNECTION
The figure below demonstrates the connection for the generator to operate at
380/440/480 V. Voltage adjustment can be made by Vad trimpot.

Figure 14 Star-series connection without auxiliary coil

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STAR-PARALLEL CONNECTION
The figure below demonstrates the connection for the generator to operate at 220 V.
Voltage adjustment can be made by Vad trimpot.

Figure 15 15 Star-parallel connection without auxiliary coil

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DELTA-SERIES CONNECTION
The figure below demonstrates the connection for the generator to operate at
380/440/480 V. Voltage adjustment can be made by Vad trimpot.

Figure 16 Delta-series connection without auxiliary coil

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DELTA-PARALLEL CONNECTION
The figure below demonstrates the connection for the generator to operate at 220V.
Voltage adjustment can be made by Vad trimpot.

Figure 17 17 Delta-parallel connection without auxiliary coil

1Item not supplied by G-MEYER COMPONENTS, observe relationship specifications

(PAR/1 or PAR/5);
2 If there is no pot connected, jump pins on jumper 6 and 7 (short-circuit);
3 5A/250Vca circuit breaker (curve C) to turn the regulator on and off (interrupt device)

* Generator line voltages, depending on the feedback class and the regulator's power
voltage level, depending on the technical characteristics.

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PARALLEL OPERATION OF TWO OR MORE GENERATORS

The reactive compensation system adopted is called fasorial composition (see figure
below). In this type of system, the generator output voltage signal is taken and the
composition is made with the generator's current signal. The result of this interaction
introduces an error in the feedback of the regulator (actual voltage signal), causing an
increase or decrease in the voltage of the generator, causing the reactive between the
generators to stay within the acceptable values. Adjustment of this compensation is done
through the Drp trimpot.

Figure 18 Fasorial Diagram of the Generator

According to the fasorial diagram, the feedback voltage is influenced by the current from
phase S that is added to the voltage of phases R and T. The influence is small in module
and large in phase, which means that there is a good compensation for reactive loads
and a small influence through active loads.

The current transformer for reactive compensation should be in the S phase of the
generator, and the feedback signal in phase R.

To certify the correct polarization of the TC, Inductive Resistive Loads should be applied
and the system responds as below.

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Examples of loads:

Resistive loads: With resistive load will not present compensation, keeping the
excitation current and generator voltage constant at the value adjusted via Vad trimpot.
If there is compensation, it indicates that the CT is in the wrong phase.

Inductive Loads: With application of inductive loads, it will show a negative

compensation, decreasing the excitation current corresponding to the adjusted gain in
the trimpot droop (0 to 10% voltage adjusted in The P1-Vad). If the compensation is
positive, it indicates that the CT is reversed.

Capacitive Loads: With application of capacitive loads, it will present a positive

compensation, increasing the excitation current corresponding to the adjusted gain in the
droop trimpot (0 to 10% voltage adjusted in the P1-Vad). If the compensation is negative
it indicates that the CT is reversed.

➢ Accuracy class of 0.6C12.5;

➢ Window or bar type;
➢ The transformation ratio will be In/5A or In/1A, where ln/xA is the primary ratio
of THE TC. E.g., 100/5A, 150/5A, 100/1A;
➢ 5A secondary current for PAR/5 and 1A regulator for regulator

PAR/1;

➢ The current in the PRIMARY OF THE TC must be 20% higher than the rated
current of the machine;
➢ The working frequency of the CT should be equal to the frequency of the
generator;
➢ The insulation voltage class of the TC should be higher than the output voltage
of the generator;
➢ It should support 1.2 x In.

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FIRST INSTALLATION OF THE VOLTAGE REGULATOR

The GRT7-TH4E/PE voltage regulator must be tested by a trained technician. Before
starting the connection make sure that the regulator is suitable for use with the generator
checking the feature label. Also make sure that existing protections.

STEPS FOR CONNECTION

1. Connect the regulator to the generator according to the description of the
terminals shown in this manual and the type of generator to be used.
2. Disconnect all loads from the generator. The generator must start without load.
The Vad potentiometer corresponding to the voltage setting must be set to the
minimum voltage to avoid over-excitation of the generator if the connection is
incorrect.
3. The generator must start without load. The P1-Vad potentiometer
corresponding to the voltage setting must be set to the minimum voltage to avoid
triggering the generator in case of incorrect connection.
4. Pots P4-Stb1 and P3-Stb2 corresponding to the stability adjustment should be
placed in half stroke. These pots only influence the dynamic response of the machine,
and should not impair the permanent regime.
5. The P5-U/F pot corresponding to the U/F protection setting must be kept in the
factory configuration where all equipments are evaluated and configured prior to
output. If there is a problem starting the generator with the U/F in place, it can be
configured during operation.
6. Connect the starting key. Priming should take less than 3 seconds. If there is no
screwing or fuse break, refer to the Defects, Causes and Solutions table contained
in this manual before consulting the manufacturer.
7. After starting, to adjust the P4-Stb1 and P3-Stb2 stability, load and then remove
until you find the point where the voltage has the lowest oscillation with the load
variation.

DISCONNECTION
With the U/F limiter set correctly, the generator shutdown is done with engine shutdown.
The voltage will gradually decrease as the frequency is protecting the generator.

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MGEN[07-00018] REV08 GRT7-TH4E/PE

CONNECTION DIAGRAM FOR BENCH TEST

Below is the diagram for connecting the bench regulator where the operation of the
equipment can be checked before plugging it into the generator.

Figure 19 Diagram connection for bench test

Material required:

• 1 - Small screwdriver;
• 1 - Incandescent lamp;
• 1 - Lamp holder;
• 1 - bipolar circuit breaker (10A/250VCA - c curve recommended);
• 1 - Extension cord;
• 1 - 110V or 220V* socket.

Procedures:

1st - Assemble circuit according to diagram below;

2nd - With a small screwdriver, turn the Vad and U/F trimpots counterclockwise until
the end of travel and connect circuit breaker;
3º - Lightly rotate the Vad trimpot clockwise (after a certain trimpot position, the lamp
should light up);
4º - With Vad trimpot adjusted for maximum voltage and lamp on, turn the trimpot
U/F clockwise (after a certain trimpot position, the U/F must act and the lamp will
remain on);
5º - Slightly rotate the Trimpot U/F counterclockwise (after a certain trimpot position,
the U/F should turn off and the lamp will remain on);
6º - With the lamp on, slowly turn the Vad trimpot counterclockwise (after a certain
trimpot position, the lamp should turn off);
7º - Turn off the circuit breaker.

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GRT7-TH4E/PE MGEN[07-00018] REV08

DIMENSIONAL
DIMENSIONAL VOLTAGE REGULATOR (mm)

Front View

Side View

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MGEN[07-00018] REV08 GRT7-TH4E/PE

SYMBOLOGY OF SERIGRAPHY
The GRT7-TH4E/PE voltage regulator has some symbology in its terminals to meet the
international standard IEC61010-1 in its 5.1.2 clause with symbols which mean the
following:

Alternated Current

Continuous Current

Care!
Risk of Shock!
Do not Touch It!

Care!
Tension!
Do not Touch It!

Care!
Hot Surface!
Do not Touch It!

FIRST USE
The GRT7-TH4E/PE voltage regulator must be managed by a trained technician. Before
starting the connection make sure that the regulator is suitable for use with the generator
checking the feature label. Also make sure that existing protections.

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GRT7-TH4E/PE MGEN[07-00018] REV08

DISCONNECTION
With the U/F protection set correctly, the generator shutdown is done by shutting down
the primary machine.

To turn off only the equipment without turning off the primary machine just turn off the
circuit breaker item 3 of the connection diagrams because terminal 3 is the power supply,
without it the regulator will not excite the excitation field of the generator, causing the
output voltage of the generator to decrease until it reaches its current voltage due to the
residual magnetism of the generator. Do not perform any disconnection procedure
without turning off the primary machine until the generator rotation is 0 rpm.

This equipment has no control over the primary machine, so it has no device for shutting
down the machine. To perform any access to the equipment, turn off the generator so
that there is no residual voltage present in the equipment terminals, thus allowing
possible access to the voltage regulator. The label below is provided in printed form in
adhesive form together with the equipment when it is bought. This label should be glued
to the access door or cover of the place where the voltage regulator will be installed.

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MGEN[07-00018] REV08 GRT7-TH4E/PE

PREVENTIVE MAINTENANCE
Periodic inspections of the equipment must be conducted to ensure that it is clean
and free from the accumulation of dust and other debris. The top of the equipment
should be checked to determine whether it is clean or dirty. It is important that all
terminals and wire connections are kept corrosion-free.

Only persons trained and authorized by the manufacturer are authorized to maintain
this equipment because improper intervention by an unqualified person may cause
damage to the equipment and generator.
To perform equipment cleaning, disconnect the equipment from the generator in
accordance with the safety standards described in this manual.

ONLY REMOVE THE EQUIPMENT WITH THE MACHINE FULLY STILL!

The equipment can be cleaned with a dry flannel, or a brush until it removes all dust
and accumulated debris.

Any damage that occurs to the equipment that makes it impossible to operate the
voltage regulator to our technical assistance to which it will evaluate and analyze it.

Do not perform any kind of repair or repair on this equipment, as only our technical
assistance is responsible for this type of maintenance.

As shown in the first paragraph, maintenance may be conducted by qualified

personnel in the voltage regulator and cleaning the equipment, as set out above.

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GRT7-TH4E/PE MGEN[07-00018] REV08

RISK REDUCTION
To reduce electrical hazards and burn hazards due to the high temperature present
in some components of the equipment, and the operator is able to freely access the
equipment should be disconnected from the primary machine (which drives the
generator) and the regulator power is disconnected, so the electrical hazards are
taken to zero because there will be no voltage reaching the equipment terminals, the
only risk it still has is the high temperature present in some components of the circuit
and can be attenuated if you wait a few minutes until the surface of the equipment
cools and the trained professional can access the equipment immediately after.

Try to execute the connections as described in this manual because as already

mentioned, if the equipment is connected incorrectly or in a manner different from
that specified in the diagrams described inthis manual the equipment may be
permanently damaged, as well as the generator in which it will be connected, and the
generator and voltage regulator may burn, compromising the protections of the
equipment increasing the safety risks (shocks, voltaic arcs, high temperatures).

The protection provided by the equipment may be impaired if it is not used in

accordance with the one specified in the manual.

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MGEN[07-00018] REV08 GRT7-TH4E/PE

NOTES TO THE PERSON RESPONSIBLE FOR

MAINTENANCE AND INSTALLATION SERVICE
There are specific risks that may affect the operator responsible for the installation or
maintenance of the equipment being:

➢ Risk of electric shock burns due to heated surfaces of the equipment, incorrect
connections, use of the regulator in a system or application not described in the
manual.

For you to obtain more security and do not run any of these risks measured above,
protective measures must be taken for such risks. Check the previous chapter to learn
how to reduce these risks.

Check the safety status of the equipment after repair, such as:

➢ Check after maintenance procedures that all connections have been made
properly and are secure.

➢ Check that the terminals of the peripherals are inaccessible.

➢ Check that the voltage regulator has been properly fixed.

➢ Check that the location where the equipment is installed has been properly
closed, so that it can only be accessed again with the use of a tool.

➢ Check the connections if they are correct as described in diagrams dand

connection in this manual.

➢ Check that the cables and connectors are meeting the specifications mentioned
in the manual.

➢ Check that the equipment is operating within the nominal conditions set out in
the manual.

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GRT7-TH4E/PE MGEN[07-00018] REV08

WARRANTY TERM

1. Warranty time: 12 months.

2. For the granting of a guarantee, all requirements below must be observed and satisfied:
2.1. The transport, handling and storage of the equipment shall be appropriate;
2.2. The installation must be done correctly and within the specified environmental conditions,
without the presence of unforeseen aggressive agents;
2.3. The condition of the network on which the equipment was installed must be within the
specified limits;
2.4. There shall be evidence of periodic conducting of appropriate preventive maintenance;
2.5. The equipment must not have undergone atmospheric discharges, overvoltages or
overcurrents above the specified limits;
2.6. Repairs and/or modifications to the equipment, if conducted, must be conducted by
persons/professionals formally authorized by G-MEYER COMPONENTS, who must have
technical qualification for the desideratum;
2.7. The buyer shall immediately notify G-MEYER COMPONENTS of defects in the
equipment and make it available for analysis to identify whether the anomalies are
manufacturing defects.
2.8. All adaptations to be performed in the application software, when provided, shall be
previously reviewed and authorized in writing by G-MEYER COMPONENTS, under penalty of
loss of warranty. G-MEYER COMPONENTS is exempt from any liability for system malfunction
altered by unauthorized persons.
3. The judgment of the requirements for the granting of warranty shall be the responsibility of
the engineering and commercial departments of G-MEYER COMPONENTS, based on the
information obtained from the customer and analysis of the equipment.
4. Not included in the Warranty:
4.1. Disassembly services at the buyer's premises;
4.2. Transportation costs, transportation, lodging and food services for the technicians of the
G-MEYER COMPONENTS;
4.3. Components whose useful life, in normal use, is shorter than the warranty period;
4.4. The following components are also excluded: FUSES, LAMPS, TIRISTORES,
POWER TRANSITORs, POWER DIODES AND VARISTORES;
5. Repair and/or replacement of parts or products, at G-MEYER COMPONENTS' discretion,
during the warranty period, does not extend the original warranty period;
6. This warranty is limited to the product supplied, and G-MEYER COMPONENTS is not
responsible for damage to persons, third parties, other equipment, facilities, and profits;
7. Removal of the identification label and/or serial number will result in the loss of the warranty.
G-MEYER COMPONENTS reserves the right to change the technical characteristics of its
products, as well as information, without notice.

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MGEN[07-00018] REV08 GRT7-TH4E/PE

PROBLEMS, CAUSES AND SOLUTIONS

Defect Cause Solution
Voltage generated Fall in the rotation of
Fix speed regulator.
decreases when the trigger ing machine.
applied load and Adjust the U/F limiter by turning
U/F limiter acting.
does not return the Trimpot U/F counterclockwise
Sequence of phases
Connect the sequence of phases
(R-S-T) incorrectly
correctly.
connected.
Movement of Polarize CT in phase correctly, as
reactive between below:
CT connected inverted.
generators when
operating in parallel
Increase the adjustment of the
Exceptionally low droop
droop by turning the Drp trimpot
adjustment.
clockwise.
Adjust trimpot Stb.
Misfit dynamics. Place 15R/200W resistor in series
Generated voltage with the field.
oscillates to empty Generator Check that the U/f limiter is working
excitation voltage if you are increasing the rotation of
too low. the primary machine.

Voltage oscillates at a Third harmonic of Eliminate auxiliary coil and connect

specific load point high auxiliary coil. according to diagram.
With the regulator on, use external
Residual voltage
battery (12Vcc) to force excitation
too low.
(*).
Generator does not Posts F+ and F-
Reverse F+ and F-.
stool inverted.
Low or
Adjust the voltage reference to the
disconnected
nominal generator specification.
feedback voltage.
Check that the generator phases
Wrong connection. are present in the feedback and
that the connection is in manual.

Defective electronic Check the operation of the

circuit regulator with the bench test.
Voltage fires

Feedback voltage
Exchange it for another model that
incompatible with
meets the application.
the regulator.

(*) For generator panel battery where the generator neutral is grounded, independent battery
should always be used.

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GRT7-TH4E/PE MGEN[07-00018] REV08

Leopoldo Veloso Street, 85

Vila Lenzi - Jaraguá do Sul, SC
+55 (47) 3305-8900

42 Commercial Contact: vendas@gmeyerequipamentos.com.br