Nidec LEROY-SOMER LSA 40, Руководство по установке и обслуживанию

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2018.11 / m
14
Electric Power Generation
Installation and maintenance
LSA 40
Low Voltage Alternators - 4 pole
4455 en -
4.5 - Electrical faults
Fault Action Effect Check/Cause
No volt-
age at no
load on
start-up
Connect a new
battery of 4 to 12
volts to termi-
nals E- and E+,
respecting the
polarity, for 2 to 3
seconds
The alternator builds up and
its voltage is still correct
when the battery is removed
- Lack of residual magnetism
The alternator builds up but
its voltage does not reach
the rated value when the
battery is removed
- Check the connection of the voltage reference
to the AVR
- Faulty diode
- Armature short-circuit
The alternator builds up but
its voltage disappears when
the battery is removed
- Faulty AVR
- Field windings open circuit (check winding)
- Main field winding open circuit (check the
resistance)
Voltage
too low
Check the drive
speed
Correct speed
Check the AVR connections (possible AVR failure)
- Field windings short-circuited
- Rotating diodes burnt out
- Main field winding short-circuited - Check the
resistance
Speed too low
Increase the drive speed (do not touch the AVR
voltage pot. (P2) before running at the correct
speed)
Voltage
too high
Adjust AVR volt-
age potentiometer Adjustment ineffective
Faulty AVR
Voltage
oscilla-
tions
Adjust AVR stabil-
ity potentiometer
If no effect : try normal / fast
recovery modes (ST2)
- Check the speed : possibility of cyclic irregularity
- Loose connections
- Faulty AVR
- Speed too low when on load (or LAM set too
high)
Voltage
correct
at no load
and too
low when
on load
(*)
Run at no load
and check the
voltage between
E+ et E- on the
AVR
Voltage between E+ and E–
SHUNT < 6V - AREP < 10V - Check the speed (or LAM set too high)
Voltage between E+ and E–
SHUNT > 10V - AREP >
15V
- Faulty rotating diodes
- Short-circuit in the main field. Check the
resistance.
- Faulty exciter armature. Check the resistance.
(*) Warning : During single-phase operation, check that the sensing wires from the AVR are connected to the
correct output terminals.
Voltage
disap-
pears
during
operation
Check the AVR,
the surge
suppressor, the
rotating diodes,
and replace any
defective
components
The voltage does not return
to the rated value
- Exciter winding open circuit
- Faulty exciter armature
- Faulty AVR
- Main field open circuit or short-circuited
(**) Warning : The AVR internal protection may cut in (overload lost connection, short circuit).