LED flicker

[hard-work]

The TLC one said for LEDs. I saw the one in Screwfix, but it is marginal. I thought what if three 8W LEDS are fitted in the future. Then trouble. The idea is to fit a transformer that will deal with three of the max wattage of LEDs on the market.

 

[winston1]

The TLC one said for LEDs. I saw the one in Screwfix, but it is marginal. I thought what if three 8W LEDS are fitted in the future. Then trouble. The idea is to fit a transformer that will deal with three of the max wattage of LEDs on the market.

This is getting tedious.
FOR THE ELEVENTH TIME you need a proper power supply designed for LEDS.
The TLC one actually said:- "Can be used with dimmable LED lamps which are able to be controlled with a 12Vac input". Is that the type of LED your neighbour has?

If your neighbour decides to up the wattage of the LEDs in future he will have to get separate supplies for each lamp or a bigger supply. But you can't plan for what might happen in the future. He may even decide to go back to halogens, you don't know.

How about this, a real transformer, not a stupid SMPS, with up to 50 watts output.

https://www.tlc-direct.co.uk/Products/TLT50slash1.html

 

[bernardgreen]

This is getting tedious.
FOR THE ELEVENTH TIME you need a proper power supply designed for LEDS.

No Winston you are getting tedious.

Is a battery a power supply designed for 12 volt LED lamps. NO it is not....... but it will supply power to a 12 volt DC lamp be it a filament lamp or an LED lamp

The OP requires a power supply designed to supply a voltage the same as the voltage rating of the lamp. IT DOES NOT HAVE TO BE DESIGNED SPECIFICALLY FOR LEDS. The driver inside the lamp adapts the power to suit the LED elements.

 

[winston1]

The OP requires a power supply designed to supply a voltage the same as the voltage rating of the lamp. IT DOES NOT HAVE TO BE DESIGNED SPECIFICALLY FOR LEDS. The driver inside the lamp adapts the power to suit the LED elements.

He needs a power supply designed to supply a voltage AND FREQUENCY the same as the voltage AND FREQUENCY rating of the lamp. That is almost certainly 12 volts DC or 50..60 Hz AC. I've never seen LEDs claim to work at tens of kilohertz.

The only supplies readily available are 12v DC supplies sold as LED drivers or 12 volt proper transformers such as the one I linked to in my last post.

 

[hard-work]

OK, where there is disagreement:

1. Bernard says that as long as it is constant voltage or 12v ac/dc it will work.
2. Winston says it needs to be 12v ac/dc but is the frequency that matters and it has to be 50/60hz, no other hz, or no hz at all as in pure DC.

Was I right?

 

[bernardgreen]

The only supplies readily available are 12v DC supplies sold as LED drivers

That is a major part of the problem 12v DC supplies sold as LED drivers

They are not drivers. They are power supplies of variable quality and method of operation.

The driver is the circuit that controls the current through the LED element(s) of a lamp.

Connect a 12 volt supply to a 12 volt lamp that uses LED element(s) and there is a could chance it will work.

Connect a 12 volt supply to one or more LED elements and the LEDs will be destroyed as there is no LED driver to control the current through the element(s)

Connect a constant current supply to one or more LED elements and provided the output current of the constant current power supply is the same or less than the current rating of the LED element(s) there will be light.

A lot of words but the problem arises because marketing people are not using enough words when describing the various items used in LED lighting

 

[winston1]

OK, where there is disagreement:

1. Bernard says that as long as it is constant voltage or 12v ac/dc it will work.
2. Winston says it needs to be 12v ac/dc but is the frequency that matters and it has to be 50/60hz, no other hz, or no hz at all as in pure DC.

Was I right?

You are right in what you say Bernard and I said.

The manufacturers quote frequency for a reason. Go, think some more.

 

[rules&rulers]

This looks like it would do. I saw nothing at Screwfix that looked suitable.

That quote confirms you aint got much of a clue,get a qualified person in.

 

[bernardgreen]

The manufacturers quote frequency for a reason. Go, think some more.

Did you not see my explanation a couple of pages back

but unlikely to be found in a bridge rectifier intended for 50/60 Hz AC.

At high frequency the parasitic capacitance of the diodes comes into the equation. The capacitance is a bi-directional low impedance path shorting out the diode. Significant current flows from AC1 to AC2 through the parasitic capacitors even when the + and - outputs are not connected. This current heats the internals of the bridge rectifier.

 

[hard-work]

That quote confirms you aint got much of a clue,get a qualified person in.

If you have read the thread you will find I have a hell of clue.

 

[rules&rulers]

If you have read the thread you will find I have a hell of clue

6 pages of advice,84 posts and your still here asking questions.i rest my case.

 

[hard-work]

6 pages of advice,84 posts and your still here asking questions.i rest my case.

If you followed the thread, which I am sure you have not, it is a debate which I am following.

 

[winston1]

Did you not see my explanation a couple of pages back

Indeed which is why I said

The manufacturers quote frequency for a reason.

1. Bernard says that as long as it is constant voltage or 12v ac/dc it will work.
2. Winston says it needs to be 12v ac/dc but is the frequency that matters and it has to be 50/60hz, no other hz, or no hz at all as in pure DC.

And why 1 is not correct and 2 is correct.

 

[aptsys]

This looks like it would do. I saw nothing at Screwfix that looked suitable.
https://www.tlc-direct.co.uk/Produc...1LBE3DZCUY7C_fscV51XH7Hh0uEM6aA8aAvNvEALw_wcB

The Varilight one is fine.
From the datasheet "The YT50LZ may be used to control 12V a.c. LED lighting. For 12V d.c. LED lighting, use part number YT45DC12." I've separately tested them, and they have a decent 50Hz waveform that is suitable for all 12V A.C. lamps.

They're available at B&Q if you want to try one before buying multiple, but they give an output suitable for just about every 12V halogen replacement LED lamp.
http://www.diy.com/departments/varilight-transformer-115v-50w/933229_BQ.prd

If you want to please winston: http://www.screwfix.com/p/halolite-led-constant-voltage-driver-1-16w/85503

 

[winston1]

The Varilight one is fine. They're available at B&Q if you want to try one before buying multiple, but they give an output suitable for just about every 12V halogen replacement LED lamp.
http://www.diy.com/departments/varilight-transformer-115v-50w/933229_BQ.prd

FOR THE TWELTH TIME SMPS designed for halogen lights are NOT suitable for LEDs. They may appear to work but will damage and shorten the life of the LED lamp. LED lamps are quoted as requiring 50/60 Hz not tens of KHz.