Troubles, Causes And Corrective Action; Preventive Maintenance; Warranty - WEG AVR-A-OPT-06 400Hz Manual De Instalación, Operación Y Mantenimiento

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15 TROUBLES, CAUSES AND CORRECTIVE ACTION

Problems

Generated voltage decreases
when load is applied, and it
doesn't return.

Alternator voltage does not
increase.

Generated voltage oscillates
at no load.

Voltage oscillates at a specific
load point.

Voltage surges.

Blown Fuse

Damaged Power Circuit

Bad usage of AVR
(*)Always use an external battery for diesel gensets where the neutral of the alternator is grounded.

16 PREVENTIVE MAINTENANCE

Periodical inspections of the equipment are required to ensure they are clean, dust and moisture free. It is essential that
all terminal and connections are kept free from corrosion.

17 WARRANTY

See the Installation and Maintenance Manual of the WEG alternator.
24 l Automatic Voltage Regulator – AVR-A-OPT-06 400Hz
Causes

Dropping speed of the driving
machine.

U/F Limiter engaged.

Residual voltage excessively low.

Terminals F (+) and F (-) are
inverted.

Dynamic not well adjusted.

Alternator excitation voltage
excessively low.

Third harmonic of the auxiliary coil is
high.

Lack of sensing.

Faulty electronic circuit.

Sensing voltage incompatible with
regulator.

Field current greater than the AVR
rated current.

Peak current greater than the
maximum current of the AVR.

Input overvoltage, damaging
protection varistor.

Abrupt load variation with high
power.

Field current greater than the AVR
rated current.

Peak current greater than the
maximum current of the AVR.

Input overvoltage, damaging
protection varistor.

Abrupt load variation with high
power.

Damaged adjustment trimpots.

Damaged components.
Corrective Action

Correct speed regulation.
 •Adjust U/F Limiter by rotating trimpot U/F
counterclockwise.
 •With the regulator switched- on, use external battery
(12Vcc) to force excitation (*).

Invert F (+) and F (-)

Adjust trimpot Stb;
Insert 15Ω/200W resistor in series with field.


Eliminate auxiliary coil and proceed with the
connections according to the diagrams of page 17.

Check if alternator phases are present in the sensing.

If the regulator is encapsulated, replace it.

Replace fuse and evaluate the equipment.

Evaluate if there is a sudden load disconnection with
high power.

Adjust stability.

Replace AVR to an appropriate equipment

Evaluate if there is a sudden load disconnection with
high power.

Adjust stability.

Replace AVR with appropriate equipment

Send equipment for repair.

Replace AVR.