"Angel eye" wiring colour code

With my latest project completed and 'in the can', my thoughts have turned to preventing the Devil from making work for my idle hands. To that end, I have purchased a couple of 'angel eye' LED rings and a power supply with a view to mounting one, or both, concentrically around the quill of my mill. So far, so good. Here's what I've got:

This is as good a close-up as I can get of the connections:

Before I damage the LEDs, can I ask those with more expertise with electrics than me, to advise whether I am correct in assuming that the pink wire is the positive and the white is negative?

The inline black capsule is described as a voltage regulator for 12V operation. Is this necessary with the pictured power supply?

Hoping for some illuminating answers!

John

Thry are diodes. Diodes only pass current in one direction. They will, of course, have a maximum reverse voltage which they can accommodate. They also have a maximum current rating, beyond which they will overheat and thermally run away.

Does that help?

Edited By not done it yet on 04/03/2022 10:34:54

Isn't there a clue printed on the white box John? Think it shows the input and output connections otherwise contact the supplier. Unlike international thread sizes (Don't even go there) there doesn't seem to be one for far eastern electronics manufacture.

Regards Ian.

Get an AAA or AA battery and briefly touch the LED ring leads onto the battery, red one end, white on the other.

Whichever way round the LED lights, the lead on the top of the battery is the positive, the lead on the flat bottom of the battery the negative.

With a 1.5V AA/AAA battery, you will not do any harm connecting it the wrong way round for a few seconds.

Edit: oh, hang on, just noticed the bit about the black in-line regulators. You won't get 1.5V through those, so will need to desolder or piggyback directly onto the LED rings from your AA/AAA battery with some spare wire.

The in-line regulators are very odd, not seen that before. Unless you have test gear, and not knowing anything about the white brick's quality or provenance, you should probably keep the black regulators in circuit in the final build.

I notice that the white brick's 12V output has a black lead on the +ve and a red lead on the -ve, so you are wise to be cautious. 

Edited By John Doe 2 on 04/03/2022 11:27:40

Thanks all.

Ndiy. Thanks, but doesn't determine which is the positive line.

Ian, it's the angel eyes' connections that I'm querying, the power supply is clearly marked + and - and the output wires follow convention in being red and black.

John Doe2. I'll give your suggestion a try when the rain stops and post the findings for the benefit of others encountering the same dilemma.

John

Don't assume anything .... Why not use a Multi-Meter to measure the voltage on the LED contacts .... It will read positive one way (The Red +ve lead will be on the positive LED terminal) and negative the other

I've just tried mine on a bench current limiting power supply I built years ago.

Pink is +ve and it didn't start to light up until I hit about 6V

Bill

Forward drop for white LEDs is generally 3-4V, plus a drop across a series resistor, makes 6V about right.

Andrew

Just as another clue. If you look at the black boxes, they seem to be a standard design that the two halves snap together. When shortening the lead to supply a dash cam, it was easy to unsnap them and its easy to determine + and -.

Regards Ian.

Once again, thanks to all.

I have a variable voltage output power supply so I'll try gradually increasing the voltage with that, having first tried to unsnap the regulator boxes. Progress!

John

I bought the same light source for my milling column 2 years ago

Intention was to place the white power supply box in an earthed metal case at the back of the column.

Until now I did not finish that because I am a bit concerned about earth. Be aware that you connect the primary leads of the white box to 230V. At the secondary side it is connected to the led ring. The content of the white box is not from high standard and how certain can you be that never 230V comes through in case of malfunctioning?

The Angel Eyes are marked (although not too clearly) + & -

Robert Butler

All sorted. Unsnapped the voltage regulator box, only to find some bits of electronic magic soldered to a tiny PCB with no useful lettering. Resorted to connecting the leads to the power supply in what I believed to be the correct orientation i.e. pink +ve, white -ve. Turns out that was right but the eyes gave off no light until the voltage reached 9V DC with the voltage regulator in use, so perhaps that's the reason for the slightly hgher voltage than expected being needed.

Now to fit them to the mill.

Thanks, again for the input, chaps.

John

Edited By John Hinkley on 04/03/2022 14:15:11

LED’s in the ring must be connected in series, therefore required voltage is higher than, let’s say, 3.3 Volts.

You read 12V on the output of the “power supply”.

Be careful and stay save. I would place the tiny white box with that tiny PCB and CE-mark on it in an earthed box and still then you can not be sure that 230V will never escape from that. Primary and secondary tracks on that tiny PCB are not far away from each other I expect.

You need three 1.5 batteries to light a white LED.

Jouke,

Your warnings are duly noted. I intend to test various arrangements of wiring on the bench, firstly in parallel, both with and without the voltage regulators. If they go bang, I'll sweep up the ashes and start again. If I go bang, someone else will have to sweep up the ashes!

John

As already confirmed the white is negative and there is a '-' sign next to the connection to the ring. This is the ground plane on the back of the light under the white silk screen. Positive terminal has a '+' and the red wire. You can ignore the switching PSU and feed in direct to the ring at around 9V to get full brightness. Likewise the switcher will probably need at least 10V for full brightness. Depending on diameter the rings pull circa 200mA.

I would recommend removing the 'bezel' to get a more uniform light. The bezel is just superglued in place and easily cracks free.

I would also recommend not mounting the light concentrically but instead if you can have an eccentric offset. When you are working with very small tooling the 'chuck' will cast a close in shadow and if concentric mounted this shadow will be frustratingly even around where you are aiming.

I have a Fusion 360 file that accommodates various ring diameters with various quill diameters to allow the mounting body to be 3D printed. Let me know if you want a STEP file to suit your dimensions.

That may depend on the particular white LED. I routinely test them with a 3 volt lithium coin cell, and I have a string of battery operated white LEDs (from Ikea) which run off 3 volts.

George

Alan,

Thanks for the info and guidance on the rings. Likewise, I appreciate the offer of the STEP file but I don't have a 3D printer. I do, however, have a 3D router, so I'll be pressing that into use and I'm currently drawing the mounting plate to suit, such that I can utilise the built-in lugs to clip it/them to the plate.

When you refer to the switching psu, are you meaning the boxes that are called voltage regulators by the suppliers, or the power supply in the white box?

John

Sorry to confuse John.

The device in the black box that hangs off the ring light is a switching regulator. It chops the incoming DC from the car electrics and transforms it down to the voltage required by the ring. Being a switching regulator it is more efficient and there is less heat created than there would be using a linear regulator.

Here is a link to my blog showing the design. which shows the Fusion model and the offset nature. The trough is for the wiring connection to the ring. The ring gets hot glued in place and the trough filled to act as a cable clamp.

The three tapped holes are for nylon mounting screws. These holes and threads are modelled in the 3D print.

I usually stick aluminium foil on the lower surface using double sided tape. This increases the reflectivity.

I also replace the supplied black box with a 3D printed larger size version which has a 2.1mm DC socket for the external supply. I also glue a magnet to this box so it can be latched onto adjacent metalwork.

I hope that gives you some help.

Kind regards

Alan