VFD Capacitor Reforming?

One of my colleagues came across this note from ABB indicating that VFD's not in service for more than a year or two, depending on circumstances, need their capacitors reformed. Attached is the note...I wouldn't think this is an ABB specific thing is it? How much of a concern is there with this? I've never had an issue with a VFD in storage for an extended period of time...

TIA,

Greg

Pretty much an issue with any VFD that uses electrolytics on it primary DC bus. And worth paying attention to as well. Electrolytic capacitors do NOT fail gracefully nor gently if there is any plate-to-plate crystal growth or dielectric deterioration.

Excesses of temperature (especially swings) can encourage both crystal growth and dielectric deterioration.

The failure symptom (if very minor) would be bulging of the capacitor ends, or sometimes body. Slightly more serious would be blowing out the vent plug, and venting dielectric. The most common breakdown event is an extremely violent explosion, resulting in burning paper and tinfoil confetti all over, with accompanying mechanical damage to anything (or person) in the area.

Rdrast's comments apply to any equipment containing large electrolytic capacitors, not just VFD's. In fact they apply to all electrolytic capacitors but the effects and consequences v the practicality of actually reforming small components often makes this a non starter. Aside from VFD's the most common systems neeeding this type of intervention will be power supplies.
Andybr

Back in the day it was common to reform electrolytic capacitors. This may help with those that have never done it:

http://www.vcomp.co.uk/tech_tips/reform_caps/reform_caps.htm

http://www.vintage-radio.com/projects/capacitor-reformer.html