LED Lamp - Driver board question

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RedArrow

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Hello all,

Hoping one of you electrical wizzes can point me in the right direction.

My mother purchased a 120 LED lamp from The Range about 4 years ago and it has now given up the ghost. Looks like a bug shorted it (burn mark on back of pcb and blown fuse/resistor along with a fried fly!) and also has a swollen cap.

I have tinkered with Soldering and electronicas before (replaced fuses on a motherboard before) so am competent to do any soldering etc.. but just really looking for some guidance on which Driver board to get.

The Lamp has 120 LEDs that are RGB.

Please see attached the specs of the original driver board.

I've had a look online and can't really find another Driver board that matches the specs of the orignal going by the label. I've also tried searching the model, but google return no accurate results for this particular board.

This is one that i've found, which i believe may work:
https://www.ebay.co.uk/itm/164261730528
(48w one)

many thanks for all advice provided.
 

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Richard-the-ninth

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Sorry, your question is?

Oh, and the ebay item you linked to will not operate the existing light, it says output 12v, The one that has failed clearly says output 38v

If it just operates some RGB LED strip, buy some 12v RGB strip and a controller and power supply from the same supplier.
 

Bruspark

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The one that blew up was a 200mA DC constant current driver, that can supply that current over an output voltage in the range of 38 to 48 volts. (Many led lamps see their voltage change with temperature or colour switching so constant voltage is no good)

It’s left unclear how many watts it’s rated to supply but it will be 10-15 most likely.

The notation on the + - output pins is a little weird but if there’s no colour or dimmer switch on the driver it’s probably just simple DC (vs reversible pulsed etc a la Xmas lights and ropes)

You may find one on the web that does the same and it may even work. Depends how much you value the lamp and your time …
 
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BorisJ

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But not that one as the output current at 1000mA is over 4 times that required 220mA constant.
 

SolarNoob

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But not that one as the output current at 1000mA is over 4 times that required 220mA constant.
It’s a tenner, and will be less stressed. Just because it’s rated at 1A doesn’t mean it needs to supply that, that’s it maximum
 

Bruspark

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Solar Noob
Honestly you havn’t a clue

A constant current driver is not the same as a voltage source

A 1A constant current driver will hit its maximum voltage trying to force 1A through a 200 or 220mA led chain which will likely fry it

If the output of an LED driver is specified as a single mA figure and the voltage is a range it’s a constant current driver and I explained why that’s needed above … and you need to match both the voltage range and the current

Please don’t give advice that’s incorrect or out of your understanding
 
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Richard-the-ninth

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Nice find Geoff1946, I think the voltage is a tad high though?

Output Voltage (LED Driver) 100 V

RedArrow, shops like the range will often have a light made just for them (Our one has a 5' tall "Westminster clock") When a light is made just for a company it will be custom made and to a price. LED's operate 3-5 volts, by bumping up the voltage they use them in series strings, which overall means the power supply can be smaller, to make it even smaller they will cram stuff in so it has no room to ventilate, so it overheats.

Again being custom made, once the production run has been completed they change to the next thing, so it starts again.

RGB strip is very common now, could you not get some more and a suitable power supply and controller and change the stuff in your mums light?
 

RedArrow

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Hi Everyone!

Blimey didn't expect such a response on my post, i'm humbled you all took time out to lend some of your wisdom.

As for the lamp, it's a giant flower LED Lamp (like 5Ft!) that i believe cycled through colours... the LED's on it aren't on a LED Strip, like what you can pick up off ebay to put around the back of a TV or under a desk. They look like christmas tree LED if i'm being honest..

I've attached a picture of a LED, that's on the lamp.
09393526ce40fb8005b08a41f81e6779.jpg


@SolarNoob
Thanks for finding that one on Ebay - It does look very simliar in terms of the enclosure too. As the lamp also have a rather small base where the driver board goes and connects to the LED's and Mains cable.. i may have to go with that. As it would match the pre-existing one that came out of it in terms of size.

Would you say in your opinion, that this would be compatible? As @Bruspark comment seems to question it's suitability.

Or would the one @Geoff1946 suggested be better? Must check the sizes though first..


I did some research in these LED Drivers boards to check it's compatibility but to be honest, feel way out of my depth.

I guess that's why I never became a Electrician and stuck to using electronics instead! :D
 

Bruspark

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The BLT one, if I read the limited details correctly, will light the LED's at about 90% of their previous brightness. I assumed the 100v is the maximum voltage it can output but as I've said in a constant current system the current is king. Depending on the temperature and colour of the LEDS selected the voltage 200ma creates can be over a wide range (presumably 35 - 45 V covered that range in the original 220mA design).

Stop Press :) I think I've found the data sheet for that unit and I think BLT have got the 100v wrong. Its clear as mud on several issues but I think they are saying it has an open circuit voltage of 100v but in operation it can supply 200mA +/-7.5% ( a rather wide tolerance) into a 23 to 40V load voltage range. The lower current 200 vs 220mA and consequent lower peak voltage makes this an 8W unit rather than the original which was probably rated 10W or more

(Put another way, against the old unit's maximum voltage the BLT ones a bit low on max voltage but also drops the current to 200mA if that's what it actually which will compensate for that and keep the wattage within its maximum limits) *I would always prefer to run low cost drivers at 50% of rated maximum wattage but this would potentially be at max allowed . . You probably wouldn't want to put that somewhere unventilated
If it was me and nothing else more suitable turned up I'd think it may be worth giving it a cautious try - but if it gets noisy, smelly or uncomfortably hot I'd promptly abandon the idea.


data sheet
 
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BorisJ

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@SolarNoob
Thanks for finding that one on Ebay - It does look very simliar in terms of the enclosure too. As the lamp also have a rather small base where the driver board goes and connects to the LED's and Mains cable.. i may have to go with that. As it would match the pre-existing one that came out of it in terms of size.
If you go for that one the LEDs won't last long at almost 5 times their rated current.

In short DON'T DO IT.
 

SolarNoob

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Solar Noob
Honestly you havn’t a clue

A constant current driver is not the same as a voltage source

A 1A constant current driver will hit its maximum voltage trying to force 1A through a 200 or 220mA led chain which will likely fry it

If the output of an LED driver is specified as a single mA figure and the voltage is a range it’s a constant current driver and I explained why that’s needed above … and you need to match both the voltage range and the current

Please don’t give advice that’s incorrect or out of your understanding

If you go for that one the LEDs won't last long at almost 5 times their rated current.

In short DON'T DO IT.
oops sorry that’s what happens when your trying to do many things at once, of course you‘re both right, didn’t give enough attention as it’s a constant current driver.
apologies.
 

RedArrow

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If you go for that one the LEDs won't last long at almost 5 times their rated current.

In short DON'T DO IT.
Ah okay, thank you. I'll abandon that one, thanks for the forewarning.

The BLT one, if I read the limited details correctly, will light the LED's at about 90% of their previous brightness. I assumed the 100v is the maximum voltage it can output but as I've said in a constant current system the current is king. Depending on the temperature and colour of the LEDS selected the voltage 200ma creates can be over a wide range (presumably 35 - 45 V covered that range in the original 220mA design).

Stop Press :) I think I've found the data sheet for that unit and I think BLT have got the 100v wrong. Its clear as mud on several issues but I think they are saying it has an open circuit voltage of 100v but in operation it can supply 200mA +/-7.5% ( a rather wide tolerance) into a 23 to 40V load voltage range. The lower current 200 vs 220mA and consequent lower peak voltage makes this an 8W unit rather than the original which was probably rated 10W or more

(Put another way, against the old unit's maximum voltage the BLT ones a bit low on max voltage but also drops the current to 200mA if that's what it actually which will compensate for that and keep the wattage within its maximum limits) *I would always prefer to run low cost drivers at 50% of rated maximum wattage but this would potentially be at max allowed . . You probably wouldn't want to put that somewhere unventilated
If it was me and nothing else more suitable turned up I'd think it may be worth giving it a cautious try - but if it gets noisy, smelly or uncomfortably hot I'd promptly abandon the idea.


data sheet
So in a nut shell I'm stuck then, none available on the market that would suit this lamp that would run the LED's at 50% rated maximum wattage as @Bruspark mentioned in their post?

Reading through this thread and this guide:

I assume I have to try to find a driver with below specs:
AC/DC voltaget: 100-240v
Dimming: no
max of: 200mA
Output Power: 10w~?
Output Voltage: 12v
Constant Current or Voltage?

Thanks again to all that has had input so far!
 
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Bruspark

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NO! Ignore the 12V driver comment completely, they are 100% the wrong thing



AC input voltage: To include the 230-240v range for UK mains. Wider ranges that include 230-240V are fine

Dimming: not needed

Constant current output of : 220mA to match existing or 200mA (more common) if you accept the LEDs a bit dimmer

Output Power: at 220mA (and 48V) you NEED 10.65W and so you'd want at least 15W or 20W rated units if they are to last any longer than the old one. Even larger wattage ratings are probably physically to big but also OK if you find a suitable one that fits

Output Voltage: On-load voltage range to include 38 - 48 Volts at the specified 200 or 220mA , a wider range that includes 38 - 48 Volts is also OK
Theoretically you could accept a slightly lower voltage range if using a 200mA driver (e.g. 33 - 47V) as the LED voltage will be a little less with the slightly less current flowing through them

Constant Current ONLY


As said before you need to fully understand what you're doing to proceed, its at your risk, and I'd have bought a new one long ago
 
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RedArrow

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NO! Ignore the 12V driver comment completely, they are 100% the wrong thing



AC input voltage: To include the 230-240v range for UK mains. Wider ranges that include 230-240V are fine

Dimming: not needed

Constant current output of : 220mA to match existing or 200mA (more common) if you accept the LEDs a bit dimmer

Output Power: at 220mA (and 48V) you NEED 10.65W and so you'd want at least 15W or 20W rated units if they are to last any longer than the old one. Even larger wattage ratings are probably physically to big but also OK if you find a suitable one that fits

Output Voltage: On-load voltage range to include 38 - 48 Volts at the specified 200 or 220mA , a wider range that includes 38 - 48 Volts is also OK
Theoretically you could accept a slightly lower voltage range if using a 200mA driver (e.g. 33 - 47V) as the LED voltage will be a little less with the slightly less current flowing through them

Constant Current ONLY


As said before you need to fully understand what you're doing to proceed, its at your risk, and I'd have bought a new one long ago
Okay awesome stuff.

Many thanks Bruspark, i'll look for something these meets those requirements in that case.

Appreciate eveyones time to chime in and provide advice for me. Thanks! <3
 

RedArrow

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NO! Ignore the 12V driver comment completely, they are 100% the wrong thing



AC input voltage: To include the 230-240v range for UK mains. Wider ranges that include 230-240V are fine

Dimming: not needed

Constant current output of : 220mA to match existing or 200mA (more common) if you accept the LEDs a bit dimmer

Output Power: at 220mA (and 48V) you NEED 10.65W and so you'd want at least 15W or 20W rated units if they are to last any longer than the old one. Even larger wattage ratings are probably physically to big but also OK if you find a suitable one that fits

Output Voltage: On-load voltage range to include 38 - 48 Volts at the specified 200 or 220mA , a wider range that includes 38 - 48 Volts is also OK
Theoretically you could accept a slightly lower voltage range if using a 200mA driver (e.g. 33 - 47V) as the LED voltage will be a little less with the slightly less current flowing through them

Constant Current ONLY


As said before you need to fully understand what you're doing to proceed, its at your risk, and I'd have bought a new one long ago
Just wanted to double check... would this meet all those requirements in that case?

https://www.bltdirect.com/osram-20w-optotronic-21-42v-programmable-led-driver


Many thanks again @Bruspark ! :)
 
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Bruspark

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No; from the datasheet it appears that is a 500mA constant current driver.

I did try to set out the various parameters and degrees of freedom that must be met in my previous post.

Perhaps a local electronics repair centre could repair the existing driver or build/modify a replacement unit for you.
 

Geoff1946

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Don't know if this may help, but one of the sources I searched has now sent me this:


Not perfect as you would have to choose a lower or higher than original current, and a bit expensive too !
 

Bruspark

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Don't know if this may help, but one of the sources I searched has now sent me this:


Not perfect as you would have to choose a lower or higher than original current, and a bit expensive too !
Its a thought but the specified output voltage range is 3 - 42 Volts which only partly overlaps with the original's 38 - 48 V (We don't know the original LED strings voltage on the different settings so this may or may not work properly in some temperature or setting cases.

Greater probability of it working on 200mA (than 250) as that will likely drop the LED operating voltage range to 33- 46 or 47 ) Also suspect its a bit bigger
 

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