Answer Drives GT3000, Hardware & Software Manual

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GT3000 Maintenance
50 IMGT30017EN
4A.3 Preventative maintenance
VFD maintenance requirements fall into three basic categories:
1. · keep it clean
2. · keep it dry
3. · keep the connections tight.
♦
Dust on VFD hardware can cause a lack of airflow, resulting in diminished performance from heat sinks
and circulating fans.
♦
Dust on an electronic device can cause malfunction or even failure.
Dust absorbs moisture, which also contributes to failure.
♦
The air used for cleaning the dusty surface must be oil-free and dry.
♦
Heat cycles and mechanical vibration can lead to sub-standard connections.
♦
A screw has maximum clamping power at a torque value specific to its size, shape, and composition,
exceeding that torque value permanently reduces the clamping power of that screw by reducing its
elasticity and deforming it.
Periodically check:
™
Wires are not damaged
™ Terminals are tight
™
Drive and motor ambient temperature does not exceed recommended specifications
™ Boards are free of dust and condensation
™
Insulation is not damaged or discolored
™
Vents or the areas next to the drive fans are not obstructed.
ELECTRONIC BOARDS: Boards do not require particular maintenance operations. Periodically remove the dust without using
compressed air. Components sensitive to electrostatic charges are mounted on the boards.
HEATSINK: Periodically remove the dust.
FANS: Assuming an average temperature of 35°C and 20 operating hours a day, the average life of the fan is about
3-4 years. The increase in fan noise produced by the bearings and the gradual temperature increase of the
Heat sink are symptoms of possible failure.
CAPACITORS: Assuming an average temperature of 35°C and 20 operating hours a day, the average life of the electrolytic
capacitors is about 5-6 years.
Capacitor Reforming of Spare and Stored Converters
Electrolytic capacitors keep their original characteristics only if they are energized within 1 year from the supply date.
Without reforming, capacitors may be damaged when the converter starts to operate.
The reforming methods and guidelines detailed here assume that a drive has been stocked and/or used in clean and dry conditions.
It is recommended, as a general rule, that the users reform the capacitors once a year.
To determine the age of a drive, check the test date on the drive plate name.
Reforming time
The converter is kept at a safe voltage during
the reforming time required to “wake up” the
capacitors. The reforming time required depends
on how long the converter has been stocked
(non-operational):
Figure 4A.2.1
Drives stocked (non-operational) less than two (2) years: Switch the power on to the converter for a time given in Figure 1 (Method 1).
The converter “wakes up” its capacitors by itself.
CAUTION !