Danfoss VACON NX FI4, Руководство по эксплуатации

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10 Maintenance
10.1 Maintenance Schedule
In normal conditions, VACON
®
NX Inverters are maintenance-free. To maintain trouble-free operation of the unit, environmental
conditions, load, line power, and process control must be within specifications, determined by the manufacturer.
To make sure that the inverter operates correctly and has a long life, we recommend doing regular maintenance. Refer to the table for
maintenance intervals.
We also recommend recording all actions and counter values with dates and time to follow up of maintenance.
Table 16: Maintenance Intervals and Tasks
Maintenance in-
terval Maintenance task
12 months (1)
Reform the capacitors (see 10.2 Reforming the Capacitors )
If the unit was in store for much longer than 12 months and the capacitors were not charged, speak to the
factory to get instructions before connecting the power.
6–24 months (2)
• Do a check of the tightening torques of the terminals.
• Clean the heat sink.
• Clean the cooling channel.
• Make sure that the cooling fan operates correctly.
• Make sure that there is no corrosion on the terminals, the busbars, or other surfaces.
• If there is cabinet installation, do a check of the door filters.
5–7 years Change the cooling fans:
• the main fan
• the fan of the LCL filter
• the internal IP54 (UL Type 12) fan
• the cabinet cooling fan/filter
5–10 years Change the DC bus capacitors, if the DC voltage ripple is high.
1
If the unit is kept in store.
2
The interval is different in different environments.
10.2 Reforming the Capacitors
Context:
The electrolytic capacitors in the DC link rely on a chemical process to provide the insulator between the two metal plates. This process
can degrade over a period of years when the drive has been non-operational (stocked). The result is that the working voltage of the DC
link gradually falls.
The correct course of action is to ensure that the insulation layer of the capacitor is ‘reformed’ by the application of a limited current
using a DC supply. Current limiting ensures that the heat generated within the capacitor is kept at a sufficiently low level to prevent
any damage.
Maintenance Operating Guide | VACON® NX Inverters FI4-FI8
AQ299433367205en-000101 / DPD00908
104 | Danfoss A/S © 2019.07