Problems with fluorescent lighting

[ravip]

12 minutes ago, Sheryl said:

 No not that.Small black knob above and to the right of the  main settings.  It says above it O followed by a symbol  then ADJ. Someone else said it is for calibrating/xeroing the meter.

OK. That is to calibrate the dial on the Ohms scale - this compensates to the battery drain etc in the meter.

When you select one of the X1 X10 X100 scale, touch the two probes together, and turn this knob until the dial indicates 0. This has to be done every time you change the scale on the Ohms range only... eg X1 to X10 to X100 etc.

Edited February 23 by ravip

[Sheryl]

2 hours ago, MangoKorat said:

Sorry, on a second look - use the scale (red) that says AC10V but set the meter to 250.

 

I have to say that's probably the most confusingly scaled meter I've seen.

Glad it is not only me.

 

Am I right to think the line above the voltage line (the one that runs 0 - 50) is amps?

[MangoKorat]

23 minutes ago, Sheryl said:

Glad it is not only me.

 

Am I right to think the line above the voltage line (the one that runs 0 - 50) is amps?

No, I believe the amps is the one where the initial part of the scale has the wording 'Leak'.

 

I think the 10

                  50

                 250

Corresponds to volts - depending on where you have the ACV switch set and the red AC10V on the same scale = just that - if you have the switch set to 10.

 

This should help, sorry no time to read it.

 

https://overseas.sanwa-meter.co.jp/pdf/manual/analog_multitester/YX360TRF_EN.pdf

 

Its clearly the same meter but odd how the name is spelled differently.

Edited February 23 by MangoKorat

[Crossy]

Gawd there really is some total b*****ks being spoken in this thread.

 

Firstly, your 8kW heater will draw about 36A on full chat, assuming that the supply voltage isn't collapsing due to excessive load.

 

I would go and buy a cheap digital meter, they are small $$$ now and reading an analog meter is becoming a dying art. I actually have that exact meter for when I'm feeling nostalgic (actually, there are times when an analog meter is the best tool for the job)

 

LEDs shouldn't be popping rapidly unless there's something pretty wrong with the supply (or the local shops have real junk)

 

Daft question, when you replaced the fluorescents you did remove all the exiting "stuff" inside the fitting (choke, starter etc.) didn't you?

 

Anyway, task a would be to measure the incoming supply voltage with no load (everything turned off). That should be worst case for over-voltage.

 

[Crossy]

For the engineers - Your starter for 10 - What is the mirror for and how do you use it?

 

Each small division on the scale is 5V when set to 250V

So, for 220V the needle should be 4 small divisions past the 200 mark. 

 

[Crossy]

Flickering when large loads are applied is often a loose connection.

 

Get your man to check all the terminals in your distribution board, and (if it's not sealed) the meter. If the meter is sealed you'll need to get the supply authority to check.

[sometimewoodworker]

2 hours ago, Crossy said:

Gawd there really is some total b*****ks being spoken in this thread.

☔

So true

 

The flicker of the light in the shower only, strongly suggests that the shower circuit is problematic, it could be that the circuit uses cables that are too small, but that is only a possibility, it could be that the connections are not tight, this is more likely. It is quite possible that the light is sensitive to the power drop caused by the shower. It is likely that a different LED fixture will behave differently and may not be as affected by the power drop.

 

If you have the same lights in the rest of the house and they are not affected by the shower usage this is a stronger suggestion that the shower circuit itself needs looking at. 
 

Unfortunately what you really need is an actual electriction, these are hard to find for domestic installations and harder to know if they do know the job. It is possible that if you talk to the PEA boss he may have someone who moonlights in his free time 
 

[VocalNeal]

2 hours ago, Crossy said:

For the engineers - Your starter for 10 - What is the mirror for and how do you use it?

 

Parallax. AVO me hearties

[Dan O]

10 hours ago, Sheryl said:

Thank you. I will try the bulb switch tomorrow as a first step... Don't know  why I didn't think of it!! Stay tuned and I'll post the results tomorrow.

 

I too thought the afterglow must mean electrical leakage since  even turning off the circuits doesn't stop it.  But I am not clear what you mean by a "junction box"? Is it the same as the fuse box? If so, what would cause leakage there/ how to confirm it/ what can be done about it?

I use the word junction box loosely as they are seldom done here. Its were several wires may be either connected together for a single circuit (1 power wire then split to service 2 or more lights or lights and outlets)or where two separate circuit wires are running side by side next to each other. It can be a place where you light switch are and also another power wire running thru the same box as the light switch. I had this same problem where they ran 2  power line into the box where both light switches and outlet wires were. The outlet power was bleeding into the wires for the lights. 

Edited February 24 by Dan O
Spelling

[norbra]

13 hours ago, Sheryl said:

Ok thanks. This is not the immediate ptoblem, I only mentioned it as background in  case relevant. Probably shouldn't have as it seems to have distracted people.

 

You may well be right about it's cause though, makes sense . 

I hope you started at this point prior to connecting the new LED's

[Sheryl]

51 minutes ago, norbra said:

I hope you started at this point prior to connecting the new LED's

Sorry, I have no idea what you mean....?

[VocalNeal]

56 minutes ago, norbra said:

I hope you started at this point prior to connecting the new LED's

 

LED's are brilliant they stick to the fitting with magnets and have these connectors. 

 

[Crossy]

9 minutes ago, Sheryl said:

Sorry, I have no idea what you mean....?

 

Pop the cover off one of your fittings and post a photo please

[LS24]

20 minutes ago, Sheryl said:

Sorry, I have no idea what you mean....?

Sheryl, does your oyster light with cover off still have the the two circled pieces of circuitry connected or something similar? As Crossy mentioned, pop up a photo of your light without the cover. He will get your sorted 🙂

I really appreciate the expertise of the mods here.

 

[SpaceKadet]

14 hours ago, ravip said:

I assume the setting at 250 ACV is correct? - Yes

 

And where among the many different lines should one read the voltage? Is it the red line labelled AC10V or where? - Yes

 

What is the black dial on the right for? - If you are referring to the X1 X10 X100 - that's the ohms scale.  The meter should NEVER be connected to a powered circuit when on this scale. This can be used to test a broken wire, burnt out fuse, an incandescent light bulb to mention a very few simple examples.

 

from the time the  house was first wired, all the fluorescent fixtures have glowed slightly - might be due to a faulty ground.

 

But lets wait for the expert, Crossy. 

 

No!, definitely not. The switch should be set on 250 VAC, as it is, and you should read the voltage on the scale labeled 0-250. The first black one above the red.

For accuracy, you should zero the needle using the little plastic screwhead in the center of the meter.

[Sheryl]

Update:

 

1. I completely shut off the water heater and took shower without it, and found that running water at all, even without the heater, also  caused the lightb to flicker just not as rapidly. Definitely no way the water pump, located on ground floor outside the house, shares a neutral wire with the hot water heater.  So the  flickering was related to dip in power supply and presumably otherwise unrelated to the water heater which - contrary to the claim of local "electricians" - does not draw more power than it is supposed to, per the specs.

 

2. Switched the bulbs to one that was working fine elsewhere. Presto - no more flickering!! So despite being brand new, a faulty bulb. I don't think an issue with installation as handyman re-installed it several times with no change, and also same handyman installed the other bulb. (And multiple bulbs throughout the house, none of which flicker).

 

As mentioned I have very bad experience with these new LED bulbs that contain multiple round bulbs, they seem to burn out at a very rapid rate.  I have no idea why, did not happen with the old kind at all and nothing new in my wiring that I know of.

 

For more than a year these multi-bulb things were the only things locally available. Just recently these have now appeared in Home Pro:

 

https://www.homepro.co.th/p/1055118?lang=en

 

Does anyone have any experience with these -- or other brands they can recommend??

 

As for the glow problem,  I will verify if the switches are on the live wires or not. This will take time as lots of switches/lights, it's a big house.

 

From what has been said I assume that if that is ruled out then the glow is  likely due to an  issue is likely with grounding?

 

The house was completely ungrounded when initially wired (of course). I subsequently had an electrician in from Bangkok (very, very hard to arrange) who put in a large ground metal  rod into the ground at the back of the house which connects to a large green wire running down  from what I think is called the the main circuit board or distribution board:

 

 

 

 

 

I can't begin to sort out what is going on within the circuit board/box other than that there are 2 fairly large green wires coming down from the ceiling area where all the wiring is into screws at the top,   and then a number  of green wires coming off other screws and eventually one fairly large green wires snakes its way around and comes out and goes down to  the ground.  It is quite crowded inside the box and I am nto about to start touching and moving wires within it.

 

In short there is a large ground wire that leads from the circuit/distribution box to  a metal pole going deep into the ground  but I have no idea what if anything it actually accomplishes, and I also don't know where   the ground wires that run from the 2 hot water heaters up in the ceiling go or if they connect to the green wiring coming back down (presumably should). 

 

Installation of this ground did not  change the light afterglows.

 

Is there some easy way to check the effectiveness of the  grounding?

 

 

[SpaceKadet]

It is amazing to me how many people on this tread offer help without even knowing how to read an analog multimeter.

And complain about Thai electricians at the same time!

 

You cannot measure amperes with a multimeter directly. To measure you must connect it in series with the load. A potentially tricky and very dangerous situation. Don't do it at home if you don't know what you're doing. 

There are special meters to measure amperage on a live circuit. They are called clamp meters and use current transformer for measurement.

[Sheryl]

1 hour ago, Crossy said:

 

Pop the cover off one of your fittings and post a photo please

 

 

 

 

 

 

 

[Rampant Rabbit]

This  is  funny as I recently changed  all my  lightbulbs in a  condo my wife owns which I renovated and added about 10  more LEDS ( way under circuit limit) prfeviously one central hideous grandma circular fluorescant tube. They flickered............but  only between 6am and 7.30 am rest of the day and night all  fine, scratched head for ages  on this......... then one morning whilst sleeping there went outside into the general corridor  area (common area).............. all the lights  there were flickering as  well!!

Case  closed! Told wife if  renter  complains tell him  to ask  the condo manager as the whole  building was doing it

[Sheryl]

1 hour ago, SpaceKadet said:

It is amazing to me how many people on this tread offer help without even knowing how to read an analog multimeter.

And complain about Thai electricians at the same time!

 

You cannot measure amperes with a multimeter directly. To measure you must connect it in series with the load. A potentially tricky and very dangerous situation. Don't do it at home if you don't know what you're doing. 

There are special meters to measure amperage on a live circuit. They are called clamp meters and use current transformer for measurement.

This may have been what local "electrician" used on the water heater and read at 28 amps. He used something he could clamp onto the heating element.  His issue was that he insisted it should not have been more than 9 amps. (Specs say 36 amps).  Apparently he based this on labelling for about 9 kW i.e. he did not understand the difference between A and kW. 

[Crossy]

Thanks for the photo. Looks fine.

 

I was a bit worried that your man had somehow hooked up the LED unit to the existing choke/starter which could lead to "interesting" effects if it wasn't specifically designed to be that way.

 

Now you know how to read your meter did you manage to check the supply voltage?

 

[norbra]

11 minutes ago, Sheryl said:

Update:

 

1. I completely shut off the water heater and took shower without it, and found that running water at all, even without the heater, also  caused the lightb to flicker just not as rapidly. Definitely no way the water pump, located on ground floor outside the house, shares a neutral wire with the hot water heater.  So the  flickering was related to dip in power supply and presumably otherwise unrelated to the water heater which - contrary to the claim of local "electricians" - does not draw more power than it is supposed to, per the specs.

 

2. Switched the bulbs to one that was working fine elsewhere. Presto - no more flickering!! So despite being brand new, a faulty bulb. I don't think an issue with installation as handyman re-installed it several times with no change, and also same handyman installed the other bulb. (And multiple bulbs throughout the house, none of which flicker).

 

As mentioned I have very bad experience with these new LED bulbs that contain multiple round bulbs, they seem to burn out at a very rapid rate.  I have no idea why, did not happen with the old kind at all and nothing new in my wiring that I know of.

 

For more than a year these multi-bulb things were the only things locally available. Just recently these have now appeared in Home Pro:

 

https://www.homepro.co.th/p/1055118?lang=en

 

Does anyone have any experience with these -- or other brands they can recommend??

 

As for the glow problem,  I will verify if the switches are on the live wires or not. This will take time as lots of switches/lights, it's a big house.

 

From what has been said I assume that if that is ruled out then the glow is  likely due to an  issue is likely with grounding?

 

The house was completely ungrounded when initially wired (of course). I subsequently had an electrician in from Bangkok (very, very hard to arrange) who put in a large ground metal  rod into the ground at the back of the house which connects to a large green wire running down  from what I think is called the the main circuit board or distribution board:

 

 

 

 

 

I can't begin to sort out what is going on within the circuit board/box other than that there are 2 fairly large green wires coming down from the ceiling area where all the wiring is into screws at the top,   and then a number  of green wires coming off other screws and eventually one fairly large green wires snakes its way around and comes out and goes down to  the ground.  It is quite crowded inside the box and I am nto about to start touching and moving wires within it.

 

In short there is a large ground wire that leads from the circuit/distribution box to  a metal pole going deep into the ground  but I have no idea what if anything it actually accomplishes, and I also don't know where   the ground wires that run from the 2 hot water heaters up in the ceiling go or if they connect to the green wiring coming back down (presumably should). 

 

Installation of this ground did not  change the light afterglows.

 

Is there some easy way to check the effectiveness of the  grounding?

 

 

Sheryl, You must slow down,the problem is only with the bathroom light,correct?

If that is the case then forget the rest of the house,forget about switchboards.

If you want to look further yourself you could remove the bathroom light switch cover, connect your meter, set to 250 AC and with the light switch in the OFF position, test the 2 wires connected to the switch, the meter should show near full scale deflection,if it does then test again with your heater in action,if the deflection is the same then your heater is not a problem.

If the meter deflection is reduced then you have a supply voltage problem This sould make further diagnosis easier,maybe loose connection at switch or light

 

[Will B Good]

Very odd.....we have the multiple LED type light in every room.....been going for two years.....never had a single on go down.

[SpaceKadet]

2 minutes ago, Sheryl said:

This may have been what local "electrician" used on the water heater and read at 28 amps. He used something he could clamp onto the heating element.  His issue was that he insisted it should not have been more than 9 amps. (Specs say 36 amos).  Apparently he based this on labelling for about 9 kW i.e. he did not understand the difference between A and kW. 

The are couple of other factors that might affect this slightly for A/C circuits, but generally if you divide the power rating of the appliance in Watt by the supply voltage, you should get an approximate Ampere figure. So in your case, 8000W/220V=36A.

Mind you, the power rating is the maximum, and would  generally be much lower during normal usage.

[Issanman]

Sheryl, there should be one point in your system that your ground is attached to the neutral. I believe this is called bonding.

I have seen cases of fluorescent lights glowing because some "electrician" decided that there should be additional bonding points in other parts of the system. 

Normally, the bonding should only occur within the main box and nowhere else in the system.

Multiple bonding points within the same system can cause weird stuff to happen, including glowing fluorescent lights that have already been turned off.

[spidermike007]

Flourescent lighting is horrendous. It is inefficient, ugly and belongs in the heap of history. I changed nearly every fixture in the house to accomodate LED bulbs. The light is beautiful, and they are highly efficient and save alot of electricity.

 

Just say no to flourescent lighting!

[sometimewoodworker]

37 minutes ago, Sheryl said:

1. I completely shut off the water heater and took shower without it, and found that running water at all, even without the heater, also  caused the lightb to flicker just not as rapidly. Definitely no way the water pump, located on ground floor outside the house, shares a neutral wire with the hot water heater.  So the  flickering was related to dip in power supply and presumably otherwise unrelated to the water heater which - contrary to the claim of local "electricians" - does not draw more power than it is supposed to, per the specs.

 

You have already found that the lamp that was flickering was rather substandard

 

LAMPTAN are a quality supplier so worth using but the light you illustrated uses the 4 pin fittings that were originally in you fluorescent fittings. It’s not clear if the fixture can use the 2 cables you now have

 

The flicker with the pump running is the power being dropped by the load of the pump, it will be greater if the shower is also running. This means that the voltage of the supply to your house is being dropped by the load you are using (this is not uncommon, my voltage is dropped by 20V by a 20A load, usual voltage 225v, add two showers and the water pump drops my supply down to 190v or less)

[sometimewoodworker]

16 minutes ago, norbra said:

Sheryl, You must slow down,the problem is only with the bathroom light,correct?

If that is the case then forget the rest of the house,forget about switchboards.

If you want to look further yourself you could remove the bathroom light switch cover, connect your meter, set to 250 AC and with the light switch in the OFF position, test the 2 wires connected to the switch, the meter should show near full scale deflection,if it does then test again with your heater in action,if the deflection is the same then your heater is not a problem.

If the meter deflection is reduced then you have a supply voltage problem This sould make further diagnosis easier,maybe loose connection at switch or light

 

@norbra it already obvious that the voltage is being reduced, the amount of the reduction is probably worth finding out but that will only be useful to try to get the PEA to change the supply to a phase that is not loaded as much.

[Sheryl]

19 minutes ago, spidermike007 said:

Flourescent lighting is horrendous. It is inefficient, ugly and belongs in the heap of history. I changed nearly every fixture in the house to accomodate LED bulbs. The light is beautiful, and they are highly efficient and save alot of electricity.

 

Just say no to flourescent lighting!

Ir is precisely LED that is giving me problems!!!

 

I was fine with fluorescent.  Switched to LED only because suddenly they were all fgat was available. No savings in electricity at all  noted with the change. Just constant expense and hassle of needing to replace bulbs because thd LEDs just do not last in my house for some reason. 

 

From what I am reading online issues may have to do with the "driver" component which is apparently very tempermental and does not tolerate flunctuations in  frequency well. 

[Sheryl]

34 minutes ago, Issanman said:

Sheryl, there should be one point in your system that your ground is attached to the neutral. I believe this is called bonding.

I have seen cases of fluorescent lights glowing because some "electrician" decided that there should be additional bonding points in other parts of the system. 

Normally, the bonding should only occur within the main box and nowhere else in the system.

Multiple bonding points within the same system can cause weird stuff to happen, including glowing fluorescent lights that have already been turned off.

I have no way of knowing where the ground attaches to the neutral. But  the lights were glowing before any ground was added. (This was actual one reason I put in the ground...but it did not help). 

 

Should add the glowing seems to increase as it gets later at night (?related to move power coming through in the wee hours?)