Flourescent Light Problems

[rayinkrabi]

Hi All, I've got a number of circular strip lights in my house that continuously glow dimly even when switched off. I only noticed this recently when walking around very early morning in the dark and wonder what could be the cause?

I suspect the switchs may be faulty as surely the 'live' should be completely isolated in a good setup?? Although this seems a bit odd to me as this problem is with about 6 lights in different rooms. any ideas?

[Crossy]

Classic switched neutral.

Seems to happen a great deal here, the switch has been placed in the neutral line rather than the live, time to get out your screwdriver but swapping them over may prove difficult.

[lopburi3]

And make sure you turn off breakers before you do anything else as there is likely a live wire in those fixtures and you can complete the circuit if not careful (although I had this happen with rat eating insulation and causing some current on neutral line so even if hot wire is being turned off light could still get some power). Is there any chance your main entry wires might have recently been reversed? A new breaker/Safe-T-Cut or meter work? That might make things easier to fix. This can be a very difficult fix as often wires are not available at switch.

[rayinkrabi]

Thanks Crossy & Lopburi, I'm not an electrician but your replies make a lot of sense to me..it would also explain why I got a jolt off of my kettle, shower and washing machine once.

it is possible for the main wires to have been messed up I s'pose as I had additional work carried out a couple of years ago but wouldn't that affect all my lights etc.?

[Crossy]

Getting a tingle from the washer, kettle etc. is likely because you have no effective ground connection, so that will need sorting.

If you have a neon tester (the sort you put your finger on the end of) you can readily identify the incoming live to see if things have been swapped.

The 'glow with switched neutral' problem isn't a given, many lights don't do it even if the neutral is switched, so a supply reversal may well not affect all (or even any) lights.

[lopburi3]

Which is why this is such a hard issue to troubleshoot - even in person. Do you have three wire (ground) system? Do you have some kind of GFI/RCD (Safe-T-Cut) type system to cut off current in the 30ma range in case you short to ground? If not it might be a good time to install and perhaps a complete re-wire. It is often much less expensive than we may think and could save a life.

[phoneguy702]

When i checked my house wiring i found that they had reversed the feed to the Consumer Unit. A inductive non-contact tester works well for this. After I found this i also found that the wiring to the gate bell was defective and leaking about 60v to ground. I disconnected it and will install a wireless one when i need the doorbell.

[lopburi3]

Wireless is the way to go for door bells (they do not seem to use low voltage systems for some reason).

[sirineou]

I know this is a long shot, but fluorescent light bulbs will glow when subjected to an electromagnetic field (EMF).

Do you live near electrical transmission lines, a radio transmitter, or any devise that might produce EMFs?

[rayinkrabi]

Thx again all for your help on this, I have of course googled this many times but am always getting lots of irrelevant stuff together with plenty of tech talk that I don't understand. l do my best to educate myself by researching online but this is so time consuming (there is a very good reason why a good electrician has to train for many years to earn the qualification & title).

This is why I'm so pleased with TV as there is a wealth of knowlegeable people here that can give clear answers and advice like you're all giving.

"Getting a tingle from the washer, kettle etc. is likely because you have no effective ground connection"

I thought this at the time but as these things came with only 2 pin plugs (along with my microwave, toaster etc.) I put it down to the fact they're not intended to be earthed..a bit crazy as we all know water and electricity don't mix well.

I did have a suposedly safe system installed with 3 pin sockets and safe-t-cut when the house was built just over 6 years ago but have never fully trusted it due to many faults over the years. And yes, I have had the sysytem checked out by other 'tradesmen' including a couple of fellow farangs, who said it was ok...apart from one friend who discovered a live earth wire in one of my showers! he disconnected it saying it is ok as I have a safe-t-cut (??)

Btw, I've since connected the long earth wire attached to the back of my washing machine directly into the power socket..is this correct? and is it possible to fit 3 pin plugs to the other appliances? (bearing in mind that the cables probably only have 2 wires so will have to be changed), finally, how do you check that the earthing rod and cables are really doing there job?.

[Tywais]

I know this is a long shot, but fluorescent light bulbs will glow when subjected to an electromagnetic field (EMF).

Do you live near electrical transmission lines, a radio transmitter, or any devise that might produce EMFs?

It's going to take a very strong field for that to happen. I designed an induction heater for work, not your typical stove type. I wanted to test if it could create a plasma and a fluorescent tube is a good candidate. Placed it in the induction coil running at 160 kHz and cranked it up to a couple hundred watts and nothing, no glow just got the glass hot.

[rayinkrabi]

I know this is a long shot, but fluorescent light bulbs will glow when subjected to an electromagnetic field (EMF).

Do you live near electrical transmission lines, a radio transmitter, or any devise that might produce EMFs?

Only have the normal power cables around here, no pylons etc. and all quite some distance away so I really think the problem is the wiring.

Phoneguy mentioned electricity 'leaking', how can this be? and would this lead to abnormaly high bills over time? My wife has also often mentioned this phrase and I've always just smiled and dismissed it thinking she's confused with the water system :-) but it now seems I have to apologise to her..yet again!

[Crossy]

"Getting a tingle from the washer, kettle etc. is likely because you have no effective ground connection"

I thought this at the time but as these things came with only 2 pin plugs (along with my microwave, toaster etc.) I put it down to the fact they're not intended to be earthed..a bit crazy as we all know water and electricity don't mix well.

Do your 2 pin plugs look like this? :-

If so read about Schuko plugs here http://www.crossy.co...ring/plugs.html

[sirineou]

I know this is a long shot, but fluorescent light bulbs will glow when subjected to an electromagnetic field (EMF).

Do you live near electrical transmission lines, a radio transmitter, or any devise that might produce EMFs?

It's going to take a very strong field for that to happen. I designed an induction heater for work, not your typical stove type. I wanted to test if it could create a plasma and a fluorescent tube is a good candidate. Placed it in the induction coil running at 160 kHz and cranked it up to a couple hundred watts and nothing, no glow just got the glass hot.

I dont know much about that, but.....

[Tywais]

I know this is a long shot, but fluorescent light bulbs will glow when subjected to an electromagnetic field (EMF).

Do you live near electrical transmission lines, a radio transmitter, or any devise that might produce EMFs?

It's going to take a very strong field for that to happen. I designed an induction heater for work, not your typical stove type. I wanted to test if it could create a plasma and a fluorescent tube is a good candidate. Placed it in the induction coil running at 160 kHz and cranked it up to a couple hundred watts and nothing, no glow just got the glass hot.

I dont know much about that, but.....

Behavior is different at RF frequencies. For example, we use 13.56 MHz RF to generate plasma but even so high power and very close proximity as shown above. Also, my Tesla coil can light a fluorescent from 5 meters away but it is also operating at RF but around 300 thousand volts.

[lopburi3]

"Getting a tingle from the washer, kettle etc. is likely because you have no effective ground connection"

I thought this at the time but as these things came with only 2 pin plugs (along with my microwave, toaster etc.) I put it down to the fact they're not intended to be earthed..a bit crazy as we all know water and electricity don't mix well.

Do your 2 pin plugs look like this? :-

If so read about Schuko plugs here http://www.crossy.co...ring/plugs.html

This is a very important post - that plug is grounded if used with the right socket - just that the socket is not normally used here so you have to buy a plastic disk adapter with the 3rd pin or replace the plug (there are three wires and ground is attached to the metal strip).

Are you checking the Safe-T-Cut on a regular basis? Amazing how many 'electricians' will turn them to bypass mode to solve problems (they do not protect in bypass mode for anything but full current breaker).

[electau]

Both reversal of polarity ie switching on the neutral only and tingling sensation when in contact with electrical equipment is potentially hazardous. You most likely have no PE conductors or main earth. this will explain the tingling sensation

[lopburi3]

Actually believe the two pin plug comment is the key (for the tingling sensation) - he likely has a main earth if system set up with grounded outlets 6 years ago but he is just not using it without adapters for those plugs (or manual grounding if not Schuko).

[electau]

There is a large number of electrical appliances that are connected by means of a 2 core lead and 2 pin plug tops, most appliances are now fitted with a 3 core lead and 3 pin moulded TIS plug top.

RCDs/RCBOs should be tested every 3 months by the use of the test button, this causes an inbalance berween the L and N and checks the operation of the device. An RCBO with a direct switch on selectivity must never be left in the DIRECT position under normal operating conditions. The 10mA setting is recomended for socket outlets where 2 pin plug tops are used.