Mitsubishi Electric FATEC FR-A800 Manual page 122

7
REVIEW OF INSTALLATION ENVIRONMENT
Life
The smoothing electrolytic capacitor used in
the inverter is one of the components to
which the "Arrhenius equation" is applied. It
will shorten the life by half for every 10°C
increase in surrounding air temperature
(double for every 10°C decrease).
The life of other components is very much
affected by the temperature as well.
Relation between failure occurrence rate
and temperature
The inverter consists of many electronic
parts such as semiconductor devices. For
these components, the failure rate is closely
related to the surrounding temperature. It is
important to operate them at as lower
temperature as possible to reduce the failure
rate.
(3) Heat of an inverter
The amount of heat generated by the inverter depends on the inverter capacity or the motor load
factor.
Options contained in the enclosure with the inverter such as an AC reactor, DC reactor, and
brake unit (including the resistor) generate relatively large amount of heat. Consider this heat
when designing the enclosure. Generated heat amount is shown in Table 7.6.
7.3 Problems and measures when using inverter
"Arrhenius equation"
Temperature
Random failure period
Early
failure period
Surrounding air temperature
50 °C
45 °C
40 °C
Time (Year)
1
2
3
Wear-out failure
period
4
5
6
7
8
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