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UK diy (uk.d-i-y) For the discussion of all topics related to diy (do-it-yourself) in the UK. All levels of experience and proficency are welcome to join in to ask questions or offer solutions. |
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#1
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Hi all
I'm hoping somebody knows more about this than I do. We have a standard fluorescent light that has stopped working. I have replaced the tube and starter with known working ones and still light doesnt work. With the light switch on, I measured 240 volts going into the Choke, but zero volts coming out of the choke. From this I assumed the Choke was faulty (is this a correct assumption) Also I took out the Choke and no current passes through it using an Ohmmeter/ Multimeter connected across the 2 terminals. Again I figured the Choke must be faulty / open circuit from this (is this correct?) I then replaced the 40W Choke with a similar thing from an old fitting called a Ballast hoping this would fix the light. It didnt - although for some unknown reason the light did come on for about 5 minutes then died after putting the outer light casing back on for the night???? Now when I switch on, there is a very dim light just at both ends of the tube. By the way the ballast I put in is 65W (is this important when the old unit was a 40W choke. The light tubes are 40W.) I am still left wondering if the Choke is faulty, and if it is then why isnt the replacement ballast not working. (Yes I did connect it up the same way) Thanks for any help and advice (Im surprised this isnt more of a common problem - I couldnt find anyone experiencing this same problem) Regards Nick |
#2
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![]() "nick" wrote in message om... Hi all I'm hoping somebody knows more about this than I do. We have a standard fluorescent light that has stopped working. I have replaced the tube and starter with known working ones and still light doesnt work. With the light switch on, I measured 240 volts going into the Choke, but zero volts coming out of the choke. From this I assumed the Choke was faulty (is this a correct assumption) Very likely. I then replaced the 40W Choke with a similar thing from an old fitting called a Ballast hoping this would fix the light. Same thing, different name It didnt - although for some unknown reason the light did come on for about 5 minutes then died after putting the outer light casing back on for the night???? Now when I switch on, there is a very dim light just at both ends of the tube. By the way the ballast I put in is 65W (is this important when the old unit was a 40W choke. The light tubes are 40W.) I am still left wondering if the Choke is faulty, and if it is then why isnt the replacement ballast not working. (Yes I did connect it up the same way) I think the old choke has probably bitten the dust. Someone else is doubtless an expert on these things but I always try to replace like for like when swapping components - 65w is considerably more than 40w - maybe the 1st firing killed your starter. Thanks for any help and advice (Im surprised this isnt more of a common problem - I couldnt find anyone experiencing this same problem) Regards Nick |
#3
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![]() "nick" wrote in message om... Hi all I'm hoping somebody knows more about this than I do. We have a standard fluorescent light that has stopped working. I have replaced the tube and starter with known working ones and still light doesnt work. Stop there. If you've replaced both the tube and starter lamp and it still ain't working, then the fitting itself is at fault and needs replaced. You don't have to go any further with more tests and the like. You need a new fitting. With the light switch on, I measured 240 volts going into the Choke, but zero volts coming out of the choke. From this I assumed the Choke was faulty (is this a correct assumption) Also I took out the Choke and no current passes through it using an Ohmmeter/ Multimeter connected across the 2 terminals. Again I figured the Choke must be faulty / open circuit from this (is this correct?) I then replaced the 40W Choke with a similar thing from an old fitting called a Ballast hoping this would fix the light. It didnt - although for some unknown reason the light did come on for about 5 minutes then died after putting the outer light casing back on for the night???? Now when I switch on, there is a very dim light just at both ends of the tube. By the way the ballast I put in is 65W (is this important when the old unit was a 40W choke. The light tubes are 40W.) I am still left wondering if the Choke is faulty, and if it is then why isnt the replacement ballast not working. (Yes I did connect it up the same way) Thanks for any help and advice (Im surprised this isnt more of a common problem - I couldnt find anyone experiencing this same problem) Regards Nick --- BigWallop http://basecuritysystems.no-ip.com Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.495 / Virus Database: 294 - Release Date: 30/06/03 |
#4
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Yes, the choke's knackered.
You haven't come across anyone else with the problem as chokes don't often fail like this. They normally develop shorted turns and melt, then go bang. |
#5
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![]() "impvan" wrote in message m... Yes, the choke's knackered. You haven't come across anyone else with the problem as chokes don't often fail like this. They normally develop shorted turns and melt, then go bang. and stink like hell |
#6
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Chris Oates wrote:
"impvan" wrote in message m... Yes, the choke's knackered. You haven't come across anyone else with the problem as chokes don't often fail like this. They normally develop shorted turns and melt, then go bang. and stink like hell Not sure if this would apply to your 230 volt versions but I have usually found that a faulty "ballast/transformer" (as we call our 115 volt and various other voltage versions) will have an open primary/mains input winding. However ours, unless they are very old like 40 to 50 years, do not use 'starters'. ballasts for the last 40 or so years have incorporated a thermal cut out in case the ballasts overheats and AFIK it does not reset thus protecting against shorts and potential fires. And yes, some of them do ooze black 'goo'. Which these days is said to be not of the 'cancer causing' variety. i.e. PCBs! Some appliances do use just a series choke in a very simple inductive circuit to fire the fluorescent tube/s. Idea anyway. |
#7
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![]() "Terry" wrote in message ... Not sure if this would apply to your 230 volt versions but I have usually found that a faulty "ballast/transformer" (as we call our 115 volt and various other voltage versions) will have an open primary/mains input winding. However ours, unless they are very old like 40 to 50 years, do not use 'starters'. ballasts for the last 40 or so years have incorporated a thermal cut out in case the ballasts overheats and AFIK it does not reset thus protecting against shorts and potential fires. And yes, some of them do ooze black 'goo'. Which these days is said to be not of the 'cancer causing' variety. i.e. PCBs! Some appliances do use just a series choke in a very simple inductive circuit to fire the fluorescent tube/s. Idea anyway. series choke here, no thermal protection not suitable as raceway even though they are used that way. |
#8
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![]() "Chris Oates" wrote in message ... "impvan" wrote in message m... Yes, the choke's knackered. You haven't come across anyone else with the problem as chokes don't often fail like this. They normally develop shorted turns and melt, then go bang. and stink like hell You better believe it. --- BigWallop http://basecuritysystems.no-ip.com Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.495 / Virus Database: 294 - Release Date: 30/06/03 |
#9
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Terry wrote:
Chris Oates wrote: "impvan" wrote in message . com... Yes, the choke's knackered. You haven't come across anyone else with the problem as chokes don't often fail like this. They normally develop shorted turns and melt, then go bang. and stink like hell Not sure if this would apply to your 230 volt versions No, it doesn't. We have enough strike voltage without needing a step-up transformer. but I have usually found that a faulty "ballast/transformer" (as we call our 115 volt and various other voltage versions) will have an open primary/mains input winding. However ours, unless they are very old like 40 to 50 years, do not use 'starters'. ballasts for the last 40 or so years have incorporated a thermal cut out in case the ballasts overheats and AFIK it does not reset thus protecting against shorts and potential fires. And yes, some of them do ooze black 'goo'. Which these days is said to be not of the 'cancer causing' variety. i.e. PCBs! Some appliances do use just a series choke in a very simple inductive circuit to fire the fluorescent tube/s. Idea anyway. |
#10
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In article ,
BigWallop wrote: We have a standard fluorescent light that has stopped working. I have replaced the tube and starter with known working ones and still light doesnt work. Stop there. If you've replaced both the tube and starter lamp and it still ain't working, then the fitting itself is at fault and needs replaced. You don't have to go any further with more tests and the like. You need a new fitting. Hmm. It might be one of several, and or no longer available. What's wrong with fixing it? I've put electronic ballasts in old fittings before now to retain the appearance. -- *Go the extra mile. It makes your boss look like an incompetent slacker * Dave Plowman London SW 12 RIP Acorn |
#11
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Thanks for the advice
Seems that it is the choke then (still not sure why the replacement 65W ballast didnt work though - unless thats busted aswell) I will find out how much a replacement choke costs before probably buying a complete new fitting. Much Obliged Nick |
#12
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In article ,
nick wrote: I will find out how much a replacement choke costs before probably buying a complete new fitting. A 40w choke costs 3.85 + vat from TLC. -- *If tennis elbow is painful, imagine suffering with tennis balls * Dave Plowman London SW 12 RIP Acorn |
#13
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In article ,
N. Thornton wrote: Choke = ballast. Not really. A ballast refers to an 'all in one' control unit. A choke is simply an inductor. -- *If all is not lost, where the hell is it? Dave Plowman London SW 12 RIP Acorn |
#14
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#15
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