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]

what no reply yet !!!

 

[chrish_1977]

Is it 3 phase? And are the lights on the same phase as the welders? Have you tested the circuits to see if everything is ok cabling wise. If his friend has done it is he a spark?

 

[Pat Tester]

Is it 3 phase? And are the lights on the same phase as the welders? Have you tested the circuits to see if everything is ok cabling wise. If his friend has done it is he a spark?

Lights are single phase but welders are 3 phase. Circuits check out ok IR with lights removed. wired in 1.5 T&E

His friend is a half wit and not a spark, apparently he asked down the pub how to wire the job !

Two 16a 3 phase socket isolators connected in series on one breaker, this runs both welders at the same time.
They also run another Tig (single phase) on the end of a 20m extension lead. No attempt to balance the lighting across the phases at all, he also thinks it necessary to drop two feeds into a triple gang light switch when all lights are on the same phase, all T&E in 20mm conduit. The owner of the business is an arse but it's on my father in laws farm otherwise I would touch it (him) with a barge pole.

 

[KAS1]

What's this mean "Two 16a 3 phase socket isolators connected in series on one breaker," ???

 

[Pat Tester]

TP 16A mcb feeds in 2.5 singles via metal trunking into a wall mounted Rotary Isolator switch socket 3 phase 16A 4 Pin
then linked into another.
[h=1][/h]

 

[KAS1]

series ?????

 

[Pat Tester]

Well as they are sockets each connection point within the socket is wired in series with the corresponding connector.
Perhaps I should have said two wall mounted Rotary Isolator 3 phase 16A 4 Pin switch sockets on one 3 phase radial circuit. or does this still not make any sense ? Perhaps I could draw you a picture, I'll just look for some crayons.

​

 

[KAS1]

I think you'll find that's not a series circuit "two wall mounted Rotary Isolator 3 phase 16A 4 Pin switch sockets on one 3 phase radial circuit" do you know the difference between a parallel circuit and a series circuit? please do me the drawing, are you also saying the lights are on a series circuit?

 

[Pat Tester]

I'm not talking about the lights. All I have said is that the two Isolators are wired in series, see drawing

 

[KAS1]

nice drawing, so are you telling me if 2 x 3phase pieces of equipment were plugged in to these two socket they are connected in series ????

 

[Pat Tester]

no, that's not what I am saying. are you actually going to have something constructive to assist in my initial query ? or are you just cramming for the pedant Olympics ?

 

[Darkwood]

The drawing and explanation you gave show a parallel wiring system not series, the reason you are picked up on it is its basic knowledge to know the difference... if we are to aid you in your query we have to first make sure we are all singing from the same song sheet or confusion will arise.....

Now regarding the said issue you first enquired about you need to use a meter to determine the mA leakage and start switching loads on and see which circuit or item plugged into them are creating your issues... swapping standard ballast type flourescents for electronic is counter productive to lowering the leakage as the electronic ballasts have designed earth leakage where as ballast shouldn't give any.

I would also be recommending a full Electrical condition report of the premises in writing with your invoice if you believe the existing is a saety issue this will cover your back a bit but any circuit you work on will need to be safe to use and meet the requirements of the Reg's it was installed under.

 

[benji]

think your 2.5 is undersize?

 

[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