3

LAM
OFF
LAM
MODE 1
LAM
MODE 2
LAM
OFF
LAM
MODE 1
LAM

STAB. I EXC

50Hz
0

90 1

23

4 56

VOLT.

EXT.FREQ.
SET.
9
LAM
ON
LAM
OFF

KNEE

ONLY FOR
SPECIAL
CONFIG.

SERIES

SERIES

0 LSA 46.2/47.2
5000/6000
LSA 46.2/47.2
1 5000/6000

LEDS

FUSIBLES / FUSES

Installation & maintenance manual :

www.leroy-somer.com

VOIR NOTICE
SEE NOTICE

Installation and maintenance

5
MODE 2
65Hz
LAM OFF
60Hz
1 PHASE SENSING

STAT.

AVRs

SERIES

7000/8000 2

SERIES

7000/8000

LSA 49.1/50.2

S2

R 450

US

X2

Z1

E+ Z2 X1

E-

380V 220 110 0V

LSA 49.1/50.2

0
1

S1

NORMAL
1 NORMAL

0 NORMAL
NORMAL

3 PAHASES SENSING
SHUNT / AREP
3

PMG

1k

n to

RAPIDE 3
FAST
RAPIDE
FAST 2

3PH.

ive
be g
o
t
s
er
ual i
man e end us
h
This
t

50 Hz EXT FREQ
60 Hz SETTING

R 450

78

4531 en - 2014.11 / f

LEROY-SOMER

Installation and maintenance

4531 en - 2014.11 / f

R 450
AVRs

This manual concerns the alternator AVR which you have just purchased.
We wish to draw your attention to the contents of this maintenance manual. By following
certain important points during installation, use and servicing of your AVR, you can look
forward to many years of trouble-free operation.

SAFETY MEASURES
Before using your machine for the first time,
it is important to read the whole of this
installation and maintenance manual.

WARNING

All necessary operations and interventions

on this machine must be performed by a
qualified technician.

Warning symbol for an operation capable

of damaging or destroying the machine
or surrounding equipment.

Our technical support service will be pleased

to provide any additional information you
may require.
The various interventions described in
this manual are accompanied by
recommendations or symbols to alert the
user to potential risks of accidents. It is vital
that you understand and take notice of the
various warning symbols used.

Warning symbol for general danger to

personnel.

Warning symbol for electrical danger to

personnel.

Note: LEROY-SOMER reserves the right to

modify the characteristics of its products
at any time in order to incorporate the
latest technological developments. The
information contained in this document may
therefore be changed without notice.

LEROY-SOMER

Installation and maintenance

4531 en - 2014.11 / f

R 450
AVRs

CONTENTS
1 - GENERAL INFORMATION ................................................................................................4
1.1 - Description.................................................................................................................... 4
1.2 - Characteristic................................................................................................................ 4
2 - POWER SUPPLY................................................................................................................ 5
2.1 - AREP excitation system................................................................................................5
2.2 - PMG excitation system..................................................................................................6
2.3 - SHUNT or separate excitation system...........................................................................7
3 - TECHNICAL CHARACTERISTICS.....................................................................................8
3.1 - Electrical characteristics................................................................................................8
3.2 - Configurations............................................................................................................... 8
3.3 - U/F and LAM functions................................................................................................12
3.4 - Typical effects of the LAM with a diesel engine with or without a LAM (U/F only)......... 12
3.5 - AVR options ................................................................................................................ 13
4 - INSTALLATION - COMMISSIONING................................................................................14
4.1 - Electrical checks on the AVR.......................................................................................14
4.2 - Setting up.................................................................................................................... 14
4.3 - Electrical faults............................................................................................................ 17
5 - SPARE PARTS.................................................................................................................. 18
5.1 - Designation................................................................................................................. 18
5.2 - Technical support service............................................................................................18

All servicing or repair operations performed on the AVR should be undertaken by

personnel trained in the commissioning, servicing and maintenance of electrical and
mechanical components.

Copyright 2005: LEROY-SOMER MOTORS

This document is the property of:
LEROY-SOMER
It may not be reproduced in any form without prior authorization.
All brands and models have been registered and patents applied for.
3

LEROY-SOMER

Installation and maintenance

4531 en - 2014.11 / f

R 450
AVRs

1 - GENERAL INFORMATION
1.1 - Description

1.2 - Characteristic

The connection is realised by Faston

connectors and the voltage sensing is
single - phase.

The R450 AVR is supplied in a casing

designed to be mounted on a panel with
dampers.
- Operating temperature: - 30C to + 65 C.
- Storage temperature: - 55C to + 85C.
- Shocks on the base: 9 g depending on the
3 axes.
- Vibrations: less than 10 Hz, 2 mm
half-peak amplitude 10 Hz to 100 Hz: 100
mm/s, above 100 Hz: 8 g.

WARNING
The AVR is IP00, it must be incorporated
in an environment which ensures it a
IP20 protection.

140 mm
115 mm

4 holes 6.5 mm

R 450

4 56

23

4
2

50Hz

LAM
OFF
LAM
MODE 1
LAM
MODE 2
LAM
OFF
LAM
MODE 1
LAM
MODE 2

SERIES

1
SERIES

0 LSA 46.2/47.2
5000/6000

LSA 46.2/47.2
1 5000/6000

STAB. I EXC

78

90 1

VOLT.

EXT.FREQ.
SET.
9

50 Hz
60 Hz

LAM
ON
LAM
OFF

ONLY FOR
SPECIAL
CONFIG.

3
3

0 NORMAL
NORMAL

S1

NORMAL
1 NORMAL

1 PHASE SENSING

KNEE

LAM OFF

65Hz

SERIES

7000 /8000

LSA 49.1 /50.2

SERIES

7000 /8000 2

LSA 49.1 /50.2

PMG

1k

3 PAHASES SENSING
SHUNT / AREP

RAPIDE 3
FAST

RAPIDE
FAST 2

3PH.

Rotating switch
- Lam and U/F
- Voltage
- Excitation

50 Hz EXT FREQ
60 Hz SETTING

FUSIBLES / FUSES

200 mm

Installation & maintenance manual :

www.leroy-somer.com

Quad
droop

LEDS

STAT.

175 mm

S2

P4

VOIR NOTICE
SEE NOTICE

380V 220 110 0V

E- E+ Z2 X1 Z1 X2

US

P1

Voltage

P2

Stability

P3

Excitation

Overrun
indications
Fuses 10A

LEROY-SOMER

Installation and maintenance

4531 en - 2014.11 / f

R 450
AVRs

2 - POWER SUPPLY

characteristic), the second one has a

voltage proportional to the stator current
(compound characteristic : Booster effect).
The power supply voltage is rectified and
filtered before being used by the AVR
monitoring transistor.
This system provides the machine with a
short-circuit current capacity of 3 IN for 10 s.
The rotating switch should be in the AREP
position (see 3.2.3).

Both the SHUNT/AREP & PMG excitation

systems are controlled by the AVR.

2.1 - AREP excitation system

With AREP excitation, the electronic AVR is

powered by two auxiliary windings which
are independent of the voltage sensing
circuit.
The first winding has a voltage proportional
to the alternator main voltage (Shunt

STATOR : 6 wires ( T1 to T6)

STATOR : 12 wires ( T1 to T12)

MAIN FIELD

AREP SYSTEM

Aux. windings

T1 T7

T8

T3 T9

T11

T6 T12

R 450

T5

50 Hz EXT FREQ
60 Hz SETTING

4 56

1
2

50Hz

LAM
OFF
LAM
MODE 1
LAM
MODE 2
LAM
OFF
LAM
MODE 1
LAM

SERIES

1
SERIES

0 LSA 46.2/47.2
5000/6000

LSA 46.2/47.2
1 5000/6000

STAB. I EXC

78

90 1

VOLT.

EXT.FREQ.
SET.
9

LAM
ON
LAM
OFF

ONLY FOR
SPECIAL
CONFIG.

KNEE

LAM OFF

3
3

0 NORMAL
NORMAL

NORMAL
1 NORMAL

S1

5
MODE 2
65Hz
60Hz
1 PHASE SENSING

SERIES

7000 /8000

LSA 49.1 /50.2

SERIES

7000 /8000 2

LSA 49.1 /50.2

PMG

1k

3 PAHASES SENSING
SHUNT / AREP

RAPIDE 3
FAST

RAPIDE
FAST 2

3PH.

T4 T10

9 Green

Field

11 Red

6-

10 Yellow

Armature

23

5+

12 Black

Varistor

T2

S2

LEDS

STAT.

FUSIBLES / FUSES

Installation & maintenance manual :

www.leroy-somer.com

VOIR NOTICE
SEE NOTICE

380V 220 110 0V

according to voltage

E- E+ Z2 X1 Z1 X2

US

10 Yellow
11 Red
12 Black
9 Green

LEROY-SOMER

Installation and maintenance

4531 en - 2014.11 / f

R 450
AVRs

2.2 - PMG excitation system

The AVR monitors the alternator output

voltage by adjusting the excitation current.
The rotating switch should be in the PMG
position (see 3.2.3).

With PMG excitation, a permanent magnet

generator (PMG) added to the alternator
supplies the AVR with voltage which is
independent of the main alternator winding.
This system provides the machine with a
short-circuit current capacity of 3 IN for 10 s.

STATOR : 6 wires ( T1 to T6)

STATOR : 12 wires ( T1 to T12)

MAIN FIELD

PMG SYSTEM

T1 T7

PMG

5+

Field

6-

T4 T10

R 450

16
15

50 Hz EXT FREQ
60 Hz SETTING

14

4 56

23

STAB. I EXC

LAM
OFF
LAM
MODE 1
LAM
MODE 2
LAM
OFF
LAM
MODE 1
LAM
MODE 2

SERIES

1
SERIES

0 LSA 46.2/47.2
5000/6000

LSA 46.2/47.2
1 5000/6000

50Hz

90 1

VOLT.

EXT.FREQ.
SET.
9

LAM
ON
LAM
OFF

ONLY FOR
SPECIAL
CONFIG.

3
3

0 NORMAL
NORMAL

S1

NORMAL
1 NORMAL

60Hz
1 PHASE SENSING

KNEE

LAM OFF

65Hz

SERIES

7000 /8000

LSA 49.1 /50.2

SERIES

7000 /8000 2

LSA 49.1 /50.2

PMG

1k

3 PAHASES SENSING
SHUNT / AREP

RAPIDE 3
FAST

RAPIDE
FAST 2

3PH.

78

S2

LEDS

STAT.

FUSIBLES / FUSES

Installation & maintenance manual :

www.leroy-somer.com

VOIR NOTICE
SEE NOTICE

380V 220 110 0V

E- E+ Z2 X1 Z1 X2

according to voltage

16
15

T2

T8

T3 T9

T11

T6 T12

Varistor

Armature

14

US

T5

LEROY-SOMER

Installation and maintenance

4531 en - 2014.11 / f

R 450
AVRs

2.3 - SHUNT or separate excitation

system
With SHUNT excitation, the AVR is powered
by the main winding (100V to 140V 50/60 Hz ) by using X1, X2 on the AVR.
The rotating switch should be in the SHUNT/
AREP position (see 3.2.3).

STATOR : 6 wires ( T1 to T6)

STATOR : 12 wires ( T1 to T12)

MAIN FIELD

SHUNT SYSTEM

T1 T7

T2

T8

T3 T9

Varistor

Armature

6-

T4 T10

R 450

T11

T6

T12

4 56

1
2

50Hz

LAM
OFF
LAM
MODE 1
LAM
MODE 2
LAM
OFF
LAM
MODE 1
LAM

SERIES

1
SERIES

0 LSA 46.2/47.2
5000/6000

LSA 46.2/47.2
1 5000/6000

STAB. I EXC

78

90 1

VOLT.

EXT.FREQ.
SET.
9

LAM
ON
LAM
OFF

ONLY FOR
SPECIAL
CONFIG.

KNEE

LAM OFF

3
3

0 NORMAL
NORMAL

NORMAL
1 NORMAL

S1

5
MODE 2
65Hz
60Hz
1 PHASE SENSING

SERIES

7000 /8000

LSA 49.1 /50.2

SERIES

7000 /8000 2

LSA 49.1 /50.2

PMG

1k

3 PAHASES SENSING
SHUNT / AREP

RAPIDE 3
FAST

RAPIDE
FAST 2

3PH.

T5

50 Hz EXT FREQ
60 Hz SETTING

Field

23

5+

S2

LEDS

STAT.

FUSIBLES / FUSES

Installation & maintenance manual :

www.leroy-somer.com

VOIR NOTICE
SEE NOTICE

380V 220 110 0V

E- E+ Z2 X1 Z1 X2

US

according to voltage
X1
X2

LEROY-SOMER

Installation and maintenance

4531 en - 2014.11 / f

R 450
AVRs

3 - TECHNICAL CHARACTERISTICS
3.1 - Electrical characteristics
- maximum power supply: 150V - 50/60 Hz
- Rated overload current: 10 A - 10 s
- Electronic protection:
- In the case of a short-circuit, the excitation
current is reduced to a value less than 1A
after 10 s
- In the event of loss of voltage reference,
the excitation current is reduced to a value
less than 1A after 1s for AREP/SHUNT, 10 s
for PMG.
- In the event of overexcitation, the current
is reduced as indicated in the next diagram
(see 3.2.1.4).
- Fuses: F1 on X1 and F2 on Z2 10A, 250V.
- Voltage sensing
0-110 V terminals = 95 to 140 V
0-220 V terminals = 170 to 260 V
0-380 V terminals = 340 to 528 V
For other voltages, a transformer should be
used.
- Voltage regulation: 0.5%.
- Current sensing: (parallel operation): input
S1, S2 intended for 1 C.T. < 2.5 VA cl1,
secondary 1 A or 5 A.

3.2 - Configurations:
3.2.1 - Settings
3.2.1.1 - Voltage
Voltage adjustment via potentiometer P1 in
the ranges described in the table below:
For 50 and 60 Hz
High range
Low range

Max.
320V < Un 530 V
80 V Un 320 V

WARNING
The allowed adjustment range is 5%;
when the setting exceeds these limits,
please check that it is conform with the
power table.

3.2.1.2 - Quadrature droop:

Quadrature
droop
adjustment
via
potentiometer P4 within a range :
- from 0 to 8% with a PF=0.8 for 400V
applications.
- From 0 to 14% with a PF=0.8 for 240V
applications.
- From 0 to 8% for 110V applications with a
step-up transformer (ratio of 4) placed on
the voltage reference.
The potentiometer P4 has a non linear
response. Then, when a 1A secondary CT is
connected the effective range starts from
the the second 1/3 of P4 range and in the
case of a 5A secondary CT the effective
range starts from the first 1/3.
When a 5A CT is used, the adjustment range
is higher, so P4 must be set to the first 1/4
(anti-clockwise) and then progressively
increase it.

WARNING
The CT must be connected.
3.2.1.3 - Stability:
Stability adjustment via potentiometer P2.
Selection of rotating switch according to the
machine type and the response time as
indicated in paragraph 3.2.3.
3.2.1.4 - Excitation limitation:
Excitation limitation adjustment via
potentiometer P3 as described below.
The excitation current limitation threshold in
steady state is set by a potentiometer at
110% of the rated value. The adjustment is
made by the operator during the on-load test
at rated power by tuning the potentiometer.
When the excitation current exceeds this
value, a counter is activated at the speed of
one record per second for 90 s. When this
time is elapsed, the current is reduced to the
value of the rated excitation current. If in the
meantime the excitation current drops
below the threshold value, the counter
counts down at the same speed.

LEROY-SOMER

Installation and maintenance

4531 en - 2014.11 / f

R 450
AVRs

excitation current must be limited to

9 A 0.5 A.

WARNING
The limitation threshold must be
adjustable between 1 and 5.5 A. The
genset breaker must be open during the
short circuit. If the genset is restarted in
short circuit, there is a excitation build
up during 10s again at the maximum
value.
Operation between 3 and 6 In when
short-circuited:
The excitation current ceiling during a
short-circuit equals 2.9 times the fixed
threshold when setting the permitted
excitation ceiling in continuous operation.
When the threshold is exceeded for a period
= 10 s the current is reduced to a value
between 0.5 and 0.7 A (shutdown).
In all operating conditions the maximum

Overrun indications:
One green LED:
- Lights up when the excitation current is
below the continuous operation threshold
It signals the AVR normal operation.
- Turns off when the excitation current ceiling
used to obtain short-circuit operation is
reached and when the excitation current is
reduced to the shutdown value.
- Flashes when the over excitation counter
is decrementing.
NB: After an obvious short-circuit, the
voltage is limited to 70% of the rated voltage.
This avoids overvoltages on machines
whose no-load excitation current is below
the lower current threshold (only in AREP).

I exc(A)
2.9x I threshold
(max. 9.5 A)

9.5

Diagram 1

(Maximum current I exc)

P3
I threshold
(1...5.5A)
Shutdown
0.5 ~ 0.7

t(s)
Activation of
90 s tempo.

Decrease of
90 s tempo.

Activation of
90 s tempo.

Activation of
10 s tempo.

10s tempo. elapsed :

shutdown apllication

Red led
Green led

LEROY-SOMER

Installation and maintenance

4531 en - 2014.11 / f

R 450
AVRs

I exc(A)
2.9x I threshold
(max. 9.5 A)

9.5

(Maximum current I exc)

Diagram 2

P3
I threshold
(1...5.5A)
Shutdown
0.5 ~ 0.7

t(s)
Activation of
90 s. tempo

90 s. tempo elapsed : application

of permanent limitation

Red led
Green led

One red LED:

- Lights up simultaneously with the green led
when the continuous operation threshold is
reached for more than 90 s and the excitation
current is reduced to the continuous
operation threshold. It is used to set the
excitation current ceiling
- Turns off when the excitation current is less
than the setting value (< 110% In)
- Flashes when the excitation current is
above the continuous operation threshold
during less than 90 s.
Green LED stays on,
- flashes when the excitation current has
reached the ceiling in < 10s with PMG
excitation.
- ftays on if Iexc = I Shutdown.

10

WARNING
If the overload protection is activated, a
voltage drop possibly exceeding 10% of
the reference voltage will be observed.
The AVR does not provide undervoltage
protection. The customer will need to
make sure that their installation is
correctly protected against undervoltages.
During load shedding, an overvoltage is
observed, which will disappear in a few
seconds.

LEROY-SOMER

Installation and maintenance

4531 en - 2014.11 / f

R 450
AVRs

KNEE

65Hz
LAM OFF

78

456

3
4

60Hz

For Pavers and hydraulic applications,

select positions 0 (50 Hz) or 3 (60 Hz).

0 NORMAL
NORMAL

PMG

NORMAL
1 NORMAL

0: AREP excitation and normal time

response.
3: AREP excitation and fast time response.
1: PMG excitation and normal time response.
2: PMG excitation and fast time response.
For SHUNT applications, AREP excitation
must be selected.
3.2.4 Rotating switch: voltage sensing

1 PHASE SENSING

SERIES

LSA 49.1/50.2

7000/8000

SERIES

LSA 49.1/50.2

SERIES

0 LSA 46.2/47.2
5000/6000

WARNING

RAPIDE
FAST 2

AREP

- Pos 0: Change in the voltage according to

the U/F ratio, knee-point position at 48 Hz.
- Pos 1: Change in the voltage according to
the 2U/F, knee-point position at 48 Hz.
- Pos 2: Change in the voltage according to
the self auto-adaptating LAM combined with
2U/F, knee-point position at 48 Hz.
- Pos 3: Change in the voltage according to
the U/F ratio, knee-point position at 58 Hz
- Pos 4: Change in the voltage according to
the 2U/F, knee-point position at 58 Hz.
- Pos 5: Change in the voltage according to
the self auto-adaptating LAM combined with
2U/F, knee-point position at 58 Hz.
- Pos 6: Change in the voltage according to
the U/F ratio, knee-point position at 65 Hz
(Tractelec application and variable speed
above 1800 rpm).
- Pos 7: Special (not used).
- Pos 8: Change in the voltage according to
the U/F ratio, knee-point position at 48 Hz or
58 Hz according to selection of the frequency
by an external contact.
- Pos 9: Change in the voltage according to
LAM 1, knee-point position at 48 Hz or 58 Hz
according to selection of the frequency by
an external contact

RAPIDE 3
FAST

ONLY FOR
SPECIAL
CONFIG.

LAM
OFF
LAM
MODE 1
LAM
MODE 2
LAM
OFF
LAM
MODE 1
LAM
MODE 2

901

23

LAM
OFF

50Hz

EXT.FREQ.
LAM SET.
9
ON

3.2.3 Rotating switch: excitation type

and time response

3.2.2 - Rotating switch selection: LAM

and U/F

7000/8000 2

SERIES

LSA 46.2/47.2
1 5000/6000

ONLY WITH
EXTERNAL R731 MODULE

3 PHASES SENSING

0: Single phase sensing

- LSA46.2/47.2 series.
3: Single phase sensing
- LSA49.1/50.2 series.
1: Three-phase sensing with optional
module R731
- LSA46.2/47.2 series.
2: Three-phase sensing with optional
module R731
- LSA49.1/50.2 series.

11

LEROY-SOMER

Installation and maintenance

4531 en - 2014.11 / f

R 450
AVRs

3.3 - U/F and LAM function

3.3.1 - Frequency variation compared

with voltage (without LAM)
Bend

Voltage

48 Hz

100 %
U/UN

57.5 Hz

50 Hz

60 Hz
Frequency

50 Hz

60 Hz

Hz

3.3.2 - LAM (Load Acceptance Module)

characteristics
3.3.2.1 - Voltage drop
The LAM system is integrated in the AVR. As
standard it is active.
Role of the LAM:
On application of a load, the genset rotation
speed decreases. When it falls below the
preset frequency threshold, the LAM causes
the voltage to drop proportionately to the
frequency (LAM1) or to the active power
(LAM2) depending the the rotating switch
position. This reduces the active load scale
applied until the speed returns to its rated
value.
Hence the LAM can be used either to reduce
the speed variation (frequency) and its
duration for a given applied load, or to
increase the applied load possible for one
speed variation (turbo-charged engine).
To avoid voltage oscillations, the trip
threshold for the LAM function should be set
approximately 2 Hz below the rated
frequency.

U
Drop N 46 Hz
Drop N > 46 Hz

3.4 - Typical effects of the LAM with

a diesel engine with or without a
LAM (U/F only)
3.4.1 - Voltage
Transient voltage drop

UN
0,9

(U/f)
without LAM

with
LAM

0,8

Time

1s

2s

3s

3.4.2 - Frequency
Max. speed drop

with
LAM

Voltage

UN

0,9

U/f

LAM

0,85 UN

Time

fN

Voltage

12

3.3.2.2 - Soft voltage recovery function

During load impacts, the function helps the
genset to return to its rated speed faster with
a gradual increase in voltage according to
the principle:
- If the speed drops between 46 and 50 Hz
(in 50Hz operation), the rated voltage is
recovered by following a fast gradient.
- If the speed drops below 46 Hz, since the
engine needs more help, the voltage follows
a slow gradient as it returns to the reference
value.

without
LAM

0,8
0

48 or 58 Hz

ST3

fC

50 or 60 Hz

fN

1s

2s

Time
3s

LEROY-SOMER

Installation and maintenance

4531 en - 2014.11 / f

R 450
AVRs

3.4.3 - Power

Load on the
shaft (kW)

LAM

Variation in the load

Load shedding due to LAM

1s

2s

Time
3s

3.5 - AVR options

- Current transformer for parallel operation of....../1 A or 5 A according to the potentiometer P4 position.
- Voltage transformer (adaptation)

Equalization of voltages before

paralleling (3 F).
Possibility of coupling to the mains of
alternators already running in parallel (4F).
- R729 module: same as R726 with
additional functions.
Detection of a diode fault.
4-20 mA input.
Possibility of kVAR regulation.
- Voltage control: with an isolated
D.C. current source applied to the terminals
used for the external potentiometer:
Internal impedance 1.5 k.
A variation of 0.5 V corresponds to a
voltage adjustment of 10%.

- Remote voltage adjustment potentio

meter.
For a range of variation:
5% : 470
10% : 1 k
the power of the potentiometer can be
0.5 W, 2 W or 3 W.

The potentiometer input must be

isolated. Do not connect it to the ground.
- R 731 module: 3-phase voltage sensing
200 to 500 V, compatible with parallel
operation in balanced installations.
- R 734 module: 3-phase current and
voltage sensing for parallel operation on
unbalanced installations (unbalance >
15%).
-
R 726
module: regulation system
changed to 4 - function (see the
maintenance manual and connection
diagram).
PF regulation (2F) .

13

LEROY-SOMER

Installation and maintenance

4531 en - 2014.11 / f

R 450
AVRs

4-INSTALLATION-COMMISSIONING
4.1 - Electrical checks on the AVR

- Check that all connections have been

made properly as shown in the attached
wiring diagram.
- Check the rotating switches selections
- frequency,
- type of alternator,
- normal position (response time),
- external potentiometer,
- rated voltage,
- secondary current of the CT used,
- type of excitation.
- R450 optional operating modes

4.2 - Setting up

Factory setting

Pot.

Voltage
minimum fully
anti-clockwise

Action

400 V - 50 Hz

P1

Stability

Not set
(centre position)

P2

Excitation ceiling
- Factory-sealed

10 A
maximum

P3

Voltage quadrature droop

(// operation with C.T.)
- 0 quadrature droop fully
anti-clockwise

Not set
(fully
anti-clockwise)

P4

Stability adjustments in standalone

operation
b) Install a D.C. analogue voltmeter (needle
dial) cal. 100 V on terminals F+, F- and an
A.C. voltmeter cal. 300 - 500 or 1000 V on
the alternator output terminals.
c) Check the rotating switch selection.

The various adjustments during tests

must be made by a qualified engineer. It
is essential that the drive speed
specified on the nameplate is reached
before commencing adjustment. After
operational testing, replace all access
panels or covers.
The AVR is used to make
adjustments to the machine.

any

d) Voltage potentiometer P1 at minimum,

fully anti-clockwise.
e) Stability potentiometer P2 around 1/3 in
from the anti-clockwise stop.
f) Start the engine and set its speed to a
frequency of 48 Hz for 50 Hz, or 58 for
60 Hz.

Before using the AVR, make sure that

the rotating switches have been
correctly configured with AREP/SHUNT
or PMG excitation

g) Set the output voltage to the desired

value using P1.
- Rated voltage UN for solo operation
(eg. 400 V)
- Or UN + 2 to 4% for parallel operation with
C.T. (eg. 410 V -)
If the voltage oscillates, use P2 to make
adjustments (try both directions), observing
the voltage between F+ and F- (approx.
10 V D.C.). The best response time is
obtained at the limit of the instability. If no
stable position can be obtained, try selecting
the fast position.

a) Initial potentiometer settings (see table

below)

h) Check LAM operation: depending on the

rotating switch selection.

4.2.1 - Setting up the R450

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R 450
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i) Vary the frequency (speed) around 48 or

58 Hz according to the operating frequency,
and check the change in voltage from that
observed previously (~ 15%).
j) Readjust the speed of the genset to its
rated no-load value.
Adjustments in parallel operation
Before starting work on the alternator, make
sure that the speed droop is identical for all
engines.
k) Preset for parallel operation (with C.T.
connected to S1, S2)
- Potentiometer P4 (quadrature droop) in
1/4 position in the case of 5A CT and at 1/2
position in the case of 1A CT.
Apply the rated load (PF = 0.8 inductive).
The voltage should drop by 2 to 3% (400 V).
If it increases, check that neither V and W
nor S1 and S2 have been reversed.
l) The no-load voltages should be identical
for all the alternators intended to run in
parallel.
- Couple the machines in parallel.
- By adjusting the speed, try to obtain 0 kW
power exchange.
- By altering the voltage setting P1 on one of
the machines, try to cancel (or minimise) the
current circulating between the machines.
- From now on, do not touch the voltage
settings.
m) Apply the available load (the setting is
only correct if a reactive load is available)
- By altering the speed, match the kW (or
divide the rated power of the units
proportionally)
- By altering the quadrature droop
potentiometer P4, match or divide the
currents.
4.2.2 - Max. excitation adjustment
(excitation ceiling)
In standard setting, the potentiometer P3 is
in maximum position.

However, for applications requiring an

overload protection (see 3.2.1.4), the
excitation ceiling must be adjusted by using
the following procedures in AREP and PMG.
Method 1 :
-Connect the AVR to the alternator
-apply load to 110% of rated machine rated
at PF=0.8, the green led is on and the red
one is off.
-record the excitation current value
-adjust P3 until obtaining the red led flashing,
the green one is always on.
-decrease the load to 100% and make sure
that the red led is off.
- Increase the load at 115%, check that the
red LED flashes during 90 seconds and that
the excitation current is brought back to the
above adjusted value (Iex adjusted).
Method 2 :
The rated excitation current (see machine
plate) must be multiplied by 1.1 and the
obtained value is used to set the
potentiometer P3 at the right position.
The following table must be used.
Position of
P3

I exc (A)

8h

9h

1.55

10h

1.95

11h

2.5

12h

3.15

13h

3.65

14h

4.25

15h

4.7

16h

5.15

12H
8H

16H

P3

NB: In the case of a permanent short-circuit,

the excitation current must reach 2.9 x Iex
adjusted (limited to 9.5A), during 1 second
in AREP or 10 seconds in PMG and shuts
down to a value less than 1A.
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R 450
AVRs

When the excitation current is set to the

rated value, a voltage dip is observed in
excitation current limit when the
limitation is activated and the current
limit is reached.
4.2.3 - Special type of use

WARNING
The excitation circuit F+, F- must not be
left open when the machine is running:
this will irreparably damage the AVR.
4.2.3.1 - R450 (SHUNT) field weakening

X2
Z1
X1
Z2
E+
E-

The exciter is switched off by disconnecting

the AVR power supply (1 wire on each
auxiliary winding) - contact rating 16 A 250 V A.C.
Connection is identical for resetting the AVR
internal protection.

If field weakening is used, provide field

forcing.
4.2.3.3 - R450 field forcing
(400V - 10A)

X2
Z1
X1
Z2
E+
E-

Diode

Battery (B Volt)

Exciter field winding

Field forcing
B Volt

t
Time

The exciter is switched off by disconnecting

the AVR power supply (1 wire - X1 or X2)
Contact rating: 16 A - 250 V A.C.

Applications

B Volt

Time t

Guaranteed voltage build-up

12 (1A)

1-2s

Parallel operation, de-energized

12 (1A)

1-2s

4.2.3.2 - R450 (AREP/PMG) field

weakening

Parallel operation, at standstill

12 (1A)

5 - 10 s

Frequency starting

12 (1A)

5 - 10 s

Sustained voltage on overload

12 (1A)

5 - 10 s

X2
Z1
X1
Z2
E+
E-

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R 450
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4.3 - Electrical faults

Fault

Action

Measurements

Check/Cause

The alternator builds up and its

voltage is still correct when the
battery is removed

- Lack of residual magnetism

No voltage at Connect a new battery The alternator builds up but its

no load on
of 4 to 12 V to terminals voltage does not reach the rated
start-up
F- and F+, respecting value when the battery is removed
the polarity, for 2 to 3
seconds
The alternator builds up but its
voltage disappears when the
battery is removed

Voltage too
low

Check the drive speed

- Check the connection of the voltage

reference to the AVR
- Faulty diodes
- Armature short-circuit
- Faulty AVR
- Field windings disconnected
- Revolving field coil open circuit. Check the
resistance
- Check the AVR connections and settings
(AVR faulty)
- Field windings short-circuited
- Rotating diodes burnt out
- Revolving field coil short-circuited
- Check the resistance

Correct speed

Increase the drive speed

(Do not touch the AVR voltage pot. (P1)
before running at the correct speed)

Speed too low

Voltage too
high

Adjust AVR voltage

potentiometer

Adjustment ineffective

- Faulty AVR
- 1 faulty diode

Voltage
oscillations

Adjust AVR stability

potentiometer

If no effect: try normal/fast

recovery modes

- Check the speed: possibility of cyclic

irregularity
- Loose connections
- Faulty AVR
- Speed too low when on load
(or U/F knee-point set too high)

Voltage
correct at no
load and too
low when on
load (*)

Run at no load and

check the voltage
between F+ and F- on
the AVR

Voltage between F+ and FAREP/PMG < 10 V

- Check the speed

(or U/F knee-point set too high)

Voltage between F+ and FAREP/PMG > 15 V

- Faulty rotating diodes

- Short-circuit in the revolving field coil.
Check the resistance
- Faulty exciter armature

(*) Caution: For single-phase operation, check that the sensing wires coming from the AVR are correctly connected to
the operating terminals.
Voltage
disappears
during
operation (**)

Check the AVR, the

surge suppressor, the
rotating diodes, and
replace any defective
components

The voltage does not return to the - Exciter winding open circuit
rated value
- Faulty exciter armature
- Faulty AVR
- Revolving field coil open circuit or
short-circuited
- Overload (see LED)
(**) Caution: Internal protection may be activated (overload, open circuit, short-circuit)

Caution: After operational testing or

troubleshooting, replace all access
panels or covers.
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Installation and maintenance

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AVRs

5 - SPARE PARTS
5.1 - Designation
Description

Type

Voltage regulator R 450

(AVR)

Code
AEM 110 RE 031

5.2 - Technical support service

Our technical support service will be pleased to
provide any additional information you may
require.
When ordering spare parts, you should indicate
the AVR type and code number.
Address your enquiry to your usual contact.
Our extensive network of service centres can
dispatch the necessary parts without delay.
To ensure correct operation and the safety of our
machines, we recommend the use of original
manufacturer spare parts.
In the event of failure to comply with this advice,
the manufacturer cannot be held responsible for
any damage.

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Installation and maintenance

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AVRs

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