2018.01 / g
Electric Power Generation
23
Installation and maintenance
R449 revision f
AVRs
3983 en -
- Perform one test supplying the regulator
via terminals X1 and X2, then another
supplying it via terminals Z1 and Z2.
According to frequency
200 - 240 V
(220 V)
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)
V
300 V :
D C
ST4
Voltage
5.3 - Troubleshooting table
Before taking any action on the R449 or the R726, pay careful attention to the positions of the
potentiometers and the jumpers.
5.3.1 - In case of 1F, parallel operation between alternators
Symptom
Probable causes
Solutions
Absence of voltage
on start-up, at no
load
- No residual magnetism or polarity inversion
between the excitation output and the exciter
input
- De-energising contacts open
- The speed is less than the rated speed
- Connection lost between the regulator and
the exciter
- Alternator loaded or short-circuited
- External potentiometer connected incorrectly
- Faulty regulator
- Faulty exciter or rotating diode bridge
- Fuses blown
- Voltage built-up is required
- Close this contact
- Adjust the speed.
- Check the wiring
- Remove the load from the alternator
- Check the wiring
- Test it or change it
- Check the exciter and the diodes
- Replace the fuses
Voltage too high
and adjustment
potentiometer not
operating
- Incorrect voltage at the sensing terminals
- Loss of sensing
- The external potentiometer has an incorrect
value
- Faulty regulator
- Check the wiring of the 0, 110V, 220V,
380V terminals on terminal block J1
- Check the wiring
- Set a potentiometer with the correct
value
- Test it or change it
Voltage too high,
but adjustable by
the adjustment
potentiometer
- Voltage potentiometer set too high
- Regulator sensing incorrect
- Regulator faulty
- Adjust voltage potentiometer P2 or the
external potentiometer
- Check the wiring and the sensing value,
at 0V and 110V, 220V, 380V terminals
- Test it or change it
Voltage too low, but
adjustable by the
adjustment
potentiometer
- ST3 and ST4 jumpers
- The speed is too low
- Exciter and rotating diodes
- Check the presence of the ST3 and ST4
jumpers
- Set to the correct speed
- Check the exciter and the rotating diodes
Incorrect
regulation
- Distortion of the waveform, non-linear load
- Unbalanced load
- The speed is not at the correct value
- Exciter or rotating diodes faulty
- Faulty regulator
- Contact the factory
- Balance the load or change the sensing
points
- Adjust the speed
- Check the exciter and the rotating diodes
- Test it or change it
