Rd2 Avr Settings; Wiring Diagrams For Different Circuits - Sincro SK225 Serie Manuel D'utilisation Et De Maintenance

6.4.5 RD2 AVR
The AVR controls the generator voltage. The AVR is used
to keep a constant voltage when the load and machine
parameters vary. The AVR requires a so-called sensing
connection; a power supply from a specific circuit (AUX);
an output to the exciter (+/-).
The RD2 board is a digital controller that allows you to
select the three-phase sensing (the regulator will keep
constant the average of the 3 voltages detected) or single-
phase sensing. The selection is made by dip-switch.
In case of unbalanced or distorted load, voltage regulation
accuracy could be reduced.
A frequency control progressively reduces the generator
excitation when the drive engine speed drops below a pre-
set, adjustable threshold preventing over-excitation at low
operating speeds and abating the load engage effects on
the engine.
In conclusion the regulator reaction time can be modulated
to eliminate any voltage instability that may arise.
The regulator has a dip-switch for the selection of the
working frequency. Set the dip switch (50 / 60Hz) of the
AVR board, depending on the operating frequency (50Hz
ON, 60Hz OFF).
Voltage setting: first, select the type of sensing (three-
phase or single-phase) through the dip-switch. Then turn,
moving it to the ON position, the dip-switch that shows
the voltage closest to the desired value (which must be
consistent with the connection made).
Turn ON the dip-switch:
• "115" if connected to a
and 130V
• "230" if connected to a
and 245V.
• "400" if connected to a
and 460V.
• "480" if connected to a sensing
and 520V.
The output voltage can be changed by adjusting
potentiometer "V". Run the generating set to its nominal
speed and turn until the required voltage is obtained. If a
small variation in speed causes a change in voltage, then
the under speed protection should first be calibrated.
If the voltage is set any higher than its
maximum limit the generator may be
damaged.
WARNING!
Stability adjustment: if on load voltage fluctuations are
experienced adjust potentiometer "ST", which modulates
the reaction time of the regulator to external inputs, thereby
eliminating any instability in the alternator-load system.
If the adjustment via potentiometer ST does not prove to
be sufficient, is possible also to use the dip-switch ST+ /
ST: moving it to the ON position (ST +) stability increases.
Setting of the under speed protection at 50 (60)
Hz: start up rotation of the generating set adjusting it to
obtain a frequency of 46 (56)Hz. Turn trimmer "UF" until
the voltage begins to drop. Restore nominal speed.
If the under speed is set at too low a
frequency, the generator may be damaged.
On the other hand, too high a frequency can
cause voltage drops with high loads.
WARNING!
24
sensing voltage between 100
sensing voltage between 185
sensing voltage between 340
voltage between 440
Remote voltages adjustment :
1) with potentiometer: Turn ON the dip-switch EXT-POT
(and make sure the dip switches EXT-VOLT is turned OFF).
Wire the potentiometer (5kOhm, 3W) to the terminals
"EXT POT". Run the generating set to its nominal speed
and adjust the external potentiometer and trimmer "V" to
obtain the desired voltage. The external potentiometer has
the effect of increasing the voltage value set by the "V"
trimmer.
2) Connection with controller or cosf regulator:
Turn ON the dip-switch EXT-VOLT (and make sure the dip
switches EXT-POT is turned
accepts voltage analogic input (0-10VDC, observe polarity
shown in figure) for remote voltage adjustment. To set the
system, follow this procedure:
- Decrease the voltage by turning the "V" trimmer counter-
clockwise;
- Apply half the control voltage at the "EXT pot" terminals
(5 VDC);
- Act on the "V" trimmer to bring the voltage to the nominal
value;
in this way, the external controller can increase or decrease
the output voltage.
In case the remote voltage adjustment is not used, turn
OFF the dip-switches EXT-POT and EXT-VOLT. Pay attention
not to turn ON both the dip-switches.
V ST UF
Phase Frequency
Dip-switch Dip-switch
V ST UF
A B
V ST UF
Off
On
CW
Voltage
Increase
A
A B
V
CCW
Off Voltage
Off
Decrease
On
V ST UF
On
CW
Voltage
Increase Voltage
CW
Stability
CW
increasing
Voltage
V
Decrease
CCW
Voltage
Increase
Decrease
ST
CCW
Stability
V
Voltage
CCW
Voltage
Increase
decreasing
Decrease
CW
Stability
Off
Decrease
On
Underfrequency
ST
CCW
Stability
Corner protection limit
CW Increase
CW increasing
Frequency
CW
Stability
Voltage
Increase
Increase
Decrease
Corner
Corner
CW Underfrequency
UF V
CCW CCW
Voltage
Frequency
Frequency
protection limit
ST
CCW Decrease
Increase
Stability
Decrease decreasing
Corner
Increase
UF
CCW
Frequency
Decrease
CW
Stability
Decrease
CW Corner
ST
CCW
Stability
Frequency
Increase
Increase

6.4.6 Wiring diagrams for different circuits

Corner
In the appendix of this manual there are diagrams for con-
UF
CCW
Frequency
Corner
CW
nections other than the factory star-series connection
Frequency
Decrease
Increase
(standard unless otherwise specified on order).
Corner
UF
CCW
Frequency
Decrease
OFF). The AVR regulator
Off
On
V ST UF
Voltage
Dip-switch
Off
On
Off -
+
L
On C N
A B
Off
On
Polarity of EXT. Voltage
CW
Voltage
-
+
- Increase
+
L
B C N
L
C N
Off
V
CCW
Off Voltage
On
Decrease
On
Polarity of EXT. Voltage
0V (-) Polarity of EXT. Voltage
Stability
CW
Stability
decreasing
0-10V (+)
Decrease
Off
On
ST
CCW
- Stability
+
Stability
Off L
A B C N
Increase
increasing
0V (-)
On
0-10V (+)
Connection with controller,
Observe polarity:
Corner
CW
Polarity of EXT. Voltage 0V (-)
Frequency
0-10V (+)
Increase
Corner
UF
Off CCW
Frequency
On
Decrease
0V (-)
0-10V (+)
Off
On
-
+
C
Polari
Off
On
0V
0-10V