Florescent issue query

[Pat Tester]

Hopefully someone here has the necessary experience to explain the issues below.

Metal bashing unit with two TIG welders and a Mig welder. The problem is the breakdown of the switch start fluorescent fittings. I believe the ballasts are breaking down and leaking to earth causing nuisance tripping of main the 300mA RCD. I have swapped two out so far and replaced with high frequency units, but have had to remove two more from circuit to keep the lights on.

I have been reading up and have come across information regarding welders causing odd order harmonics that can damage the fittings, can someone explain the effect and possible methods to reduce or eliminate the problems.

I should like to explain that I was not responsible for any of the electrical installation, it was done by a friend of the owner !
It has already been necessary to remedy some crap work, shorting connections in metal boxes etc.

I look forward to the usual intelligent and knowledgeable reply's...

Many thanks

 

[Pat Tester]

think your 2.5 is undersize?

not mine and on a 16A mcb

 

[Pat Tester]

Ok I will attempt to be a great deal more succinct in future posts.
I have often measured a small amount of leakage even of switch start fittings and this would be fine if consistent, the problem is the fittings are all breaking down, possibly due to the Tig welders. I have measured this hence I am aware they are failing, I also know which circuit (phase) is being affected. I have measured 65mA on half the circuit (four 6' twins)
The high frequency fittings are working without issue although I don't know if they will also succumb.
I don't think they have a huge batch of bad ballasts

A bit of the post has gone !

Apart form advanced age are there any other causes of premature failure on ballasts ? Could it be the Tig welders ? If so can the issue be rectified somehow ?

 

[Darkwood]

Query on the lights.... are energy saving lamps been used with a standard ballast designed for standard lamps as this can overheat the ballasts and give premature failure.

 

[Pat Tester]

Query on the lights.... are energy saving lamps been used with a standard ballast designed for standard lamps as this can overheat the ballasts and give premature failure.

They are bog standard T5 fluorescent tubes darkwood in switch start fittings, (as supplied when installed) I am calling them ballasts but could they be switch start chokes ? anyway, what constitutes an energy saving lamp ? used within these fittings.