![background image](http://html1.mh-extra.com/html/nidec/leroy-somer-r449/leroy-somer-r449_installation-and-maintenance-manual_1687803011.webp)
2018.01 / g
Electric Power Generation
11
Installation and maintenance
R449 revision f
AVRs
3983 en -
The maximum limitation is 15A.
The minimum limitation is when the
potentiometer has been rotated fully anti-
clockwise.
In the absence of specification to the
contrary, P5 is positioned at the clockwise
limit.
- Static adjustment of the maximum
excitation current.
For this value, the static adjustment is
possible when the alternator is stopped,
which will not endanger the alternator or the
installation.
Disconnect the power supply wires X1,X2
and Z1,Z2 and the alternator voltage
reference (terminal strip J1).
Connect the power supply, 200 to 240V, as
shown (X1 and X2: 0-220V). Install a 20
ADC ammeter in series with the exciter field.
Turn P5 fully anti-clockwise, switch on the
power supply (circuit breaker A).
If the regulator does not discharge, turn
potentiometer P2 (voltage) clockwise until
the ammeter indicates a stabilised current.
Switch the power supply off and then on
again, turn P5 clockwise until the required
excitation current is reached (limited to
15A), (for precise adjustment contact the
factory). Checking the internal protection:
Open the circuit breaker (D): the excitation
current must rise to its preset upper limit,
maintain this value for 10s and fall back
automatically to a value less than 1A.
To reset, switch off the power supply using
the circuit breaker (A). Note: After setting the
upper excitation limit using this procedure,
re-adjust the voltage.
Exciter field
~ 10 ohms
R449
X2
Z1
X1
Z2
E+
E-
0V
220V
380V
P2
P3
P5
50Hz 60Hz
S1 S2
ST1
ST2
P1
ST3
ST5
Mains (Supply 50/60 Hz)
20A DC
ST4
Excit max
Voltage
A
+
-
According to frequency
A
D
1.3.14 - Protection
There are two fuses in the power section.
They are mounted externally to the AVR but
inside the alternator terminal box. Rating:
gG 10/38 16A 500V
- ATQ20 (10x38US) 500 VAC UL/CSA
1.3.15 - Voltage build-up
The voltage build-up is automatic (no
overvoltage) from the residual magnetism.
If there is no voltage build-up, a short pulse
of continuous isolated voltage (12VDC), will
usually remedy this. Otherwise, proceed in
accordance with the diagram below to re-
establish the residual magnetism:
R449
X2
Z1
X1
Z2
E+
E-
J1
+
-
t
(12V - 10A)
Exciter field
Isolated DC
power supply
~ 10 ohms
1.3.16 - Power used
The power used by the R449 is 30W, when
the alternator is at rated power.
1.3.17 - De-energising
The regulator is de-energised by switching
off the voltage regulation power supply.
Contact rating: 15A, 250V AC
R449
X2
Z1
X1
Z2
E+
E-
Aux. windings
J1
1.4 - Environment
- Operating temperature: - 30°C to +70°C
- Storage temperature: - 55°C to + 85°C
- Shocks on the base: 9g for the 3 right-
angled directions
- Vibrations: Less than 10Hz: 2mm half peak
amplitude 10Hz to 100Hz: 100mm/s
Above 100Hz: 8g