Chapter 10 Service And Maintenance 91
NX UPS Single Module And Parallel System 250kVA ~ 800kVA User Manual
Chapter 10 Service And Maintenance
UPS system (including battery) needs regular maintenance in the long-term operation. This chapter mainly elaborates
the advice on service life, regular inspection and maintenance of UPS key components, as well as the maintenance
of UPS and the optional parts .Effective maintenance of UPS systems can reduce the risk of UPS failure and enable
longer use of UPS.
10.1 Safety
Warning
Daily inspection of the UPS system can be executed by people who have received relevant training. Component inspection and
replacement should be operated by authorized professionals.
10.2 Key Component And Service Life Of UPS
When in use, some components of the UPS system have shorter service life than the UPS due to abrasion in work.
For the sake of power supply safety of the UPS, it is necessary to inspect and replace these components periodically.
This section introduces the key components of the UPS and their reference service life. For systems under different
use conditions (environment, load and so on), professional assessment and advice on whether to replace the
components are required with reference to the information provided in this section.
10.2.1 Magnetic Component: Transformer, Inductor
The designed service life of magnetic components is 20 years. Key factors that affect their service life are the
insulation system among windings and the temperature rise in operation. H-class insulation system is used in the
UPS, which is able to tolerate temperature up to 220°C, usually working in forced air cooling conditions.
10.2.2 Power Semiconductor Component
Power semiconductor components include SCRs and IGBTs. In normal UPS working state, the power semiconductor
components have no rated years of service life. SCR and IGBT failures are always caused by other problems.
However, in system service and maintenance, it is required to check on a yearly basis for corrosion and damaged
enclosure in the appearance of the power semiconductor components, and replace those in risk of failure.
10.2.3 Electrolytic Capacitor
The actual operating life of the electrolytic capacitors is mainly affected by the DC bus voltage, capacitor ripple
current and ambient temperature of the system.
To ensure the safety and stability of the UPS system, the user must replace the electrolytic capacitors by the end of
their service life. It is recommended to replace the electrolytic capacitors after five to six years in service.
10.2.4 AC Capacitor
It is recommended to replace the AC capacitors after five to six years of continuous work, and inspect them regularly
once a half year. The abnormal ones should be replaced immediately.
10.2.5 Service Life And Recommended Replacement Time Of Key Component
The key components listed in Table 10-1 are used in the UPS system. To prevent system malfunctions caused by
component failure by wear, it is recommended to regularly inspect the components and replace them by the end of
their estimated life.
