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. System degradation and recommended replacement cycle
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TI 34M06Z42-01E
2018.06-00
2.3
Examples of failure of parts with
service life
■
Aluminium electrolytic capacitor
●
Generally, electrostatic capacitance drops, and electrolyte leakage
appears after 8 and 15 years respectively, and may cause power output
interruptions, changes in signal characteristics at power on/off and
circuit malfunction, etc.
■
Relays
●
Small relays have a mechanical life due to mechanical wear.
●
Prolonged use may result in insulation degradation due to formation of
products of corrosion or conductive dust deposit, or poor contact due
to entry of dust and foreign substances at contact points or corrosive
film build-up on contact surfaces. Replacement at the recommended
replacement cycle is advisable.
■
Photocoupler
●
Generally, the light-emitting element of a photocoupler has an
expected life, and in some FA-M3 modules, wearout failures appear
after about 5 to 6 years depending on temperature and other
environment conditions.
Figure2.2
Electrolyte leakage
Figure 2.3
Corrosion of contacts
