How dangerous is a design that has the AC 250V power in, in electrical
contact with the case of an electrolytic  capacitor.

Will it function ok as long as no one or nothing else or no one comes into
contact with the case.  Is the case isolated sufficiently from the
terminals of a cap.

This is what I found inside an Electronic Ballast.

Details follow...

I had 2 x 40 watt 240v Electronic fluorescent ballasts fail.

Decided to purchase cheap replacement from Hong Kong as I figured the
originals were poorly built as they lasted less than a year so how bad can
they get. So out of curiosity   purchased 2 each from 2 different sellers
(which turned out to be the same seller).

They were similarly priced and had these specs

Product A
Product NameFluorescent Lamp BallastWorking VoltageAC 150-250V 50/60HzPower
40WLight ColorWhiteOverall Size7 x 3.5 x 2cm/ 2.8" x 1.4" x 0.8"(L*W*H)Wire
Length8cm/ 3.1"MaterialPlastic, MetalExternal ColorWhiteWeight40gPackage
Content1 x Fluorescent Lamp Ballast

Product B
Product NameFluorescent Lamp BallastsPower40WRated Current0.19ARated Voltag=
eAC
220V, 50HzForRing Tube LampSize90 x 47 x 28mm/ 3.5" x 1.9" x 1.1" (L*W*T)Ca=
ble
Length(Approx.)14cm/ 5.5"MaterialPlasticMain ColorWhiteNet Weight58gPackage
Content1 x Fluorescent Lamp Ballasts


On arrival product A had an AC power lead missing so decided to open case.
 This revealed that in both product A items that the AC Power in lead was
in contact with the case of the capacitor.  This was due
to insufficient space made available for the capacitor and the power lead
had to be fed in under the edge of the cap. The rest of the board looked to
be of poor quality.

This led me to open Prod B case.  This revealed what appeared to my
untrained eye as a superior board, that was better laid out and components
were installed with better alignment and heavier duty cabling.

I wanted prod A as it had spec'ed a higher AC input of 250v which my supply
exceeds slightly from time to time.  However, it did not have the connector
for the fluoro tube.

Prod B had the right connectors but was spec'ed at 220V AC.  Many of the
items in available in Australia seem to have a rating of 110V - 220V but
most appear to work ok on 250V.

If it is agreed that Prod A is of dangerous  design and build quality would
it be fair that i request the seller to remove such listing
or receive negative feed back.

If interested I will happily post pictures of both boards.

Justin
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