Alpenglow lights to LED

[BigAl.NZ]

Hi Guys,

I need to convert these Apenglow lights to LED and remove the CFL.

There is a red strip / switch for night and white strip to replace the CFL.

Have not brought anything yet and it should by straight forward but on the Apendglow website they spoke of the kit they sell having heat sinks? I suppose it would be good to stand off the LED strips with little spacers (like the ones already there) - but any other suggestions?

Is heat really that much of a concern you need heat sinks?

[stormalong]

You can buy led lights on a tape, 5 meters to a roll. They can be cut at certain points, into about 4 inch multiples. The strip has a sticky back, peel off the protective paper and stick it down to the base plate. That is all heat heat sink you need. They also make a waterproof version that has silicone on top of the LEDs. Cleaning and preparing the pads for soldering the wires can be tricky on the waterproof versions.

I converted a bunch of old light fixtures on my boat this way, not Alpinglow. I used four strips wired into a high/low switch. Two strips or four on. Works quite well.

[jamhass]

I have converted several Alpenglow CFL fixtures to LED using their kits. Not a hard job, but some of the wire runs are a bit tight, as they don't want loose wires hanging in the fixture and being visible. AND, their kits don't cause RF interference, not saying the DIY approach does, just a general concern.

To be fair, I have also gone the DIY way with one Alpenglow and a few other fixtures, with only one issue: If using self-stick LED's, might be best to make sure you are NOT adhering them to a conductive surface, as some of them are not that well insulated.

[Tomodore]

Been using Alpenglow for years and been in touch with tech support there. I would follow their advice over input from this board. They are experts and want you to succeed with their product. We were one of the early boats to get a new design fixture a few years back. The light interfered with our HF radio. Called Alpenglow and 2 days later an engineer called back with a fix I installed and they upgraded the units going forward. First rate company

[BigAl.NZ]

Originally Posted by Tomodore

Been using Alpenglow for years and been in touch with tech support there. I would follow their advice over input from this board. They are experts and want you to succeed with their product. We were one of the early boats to get a new design fixture a few years back. The light interfered with our HF radio. Called Alpenglow and 2 days later an engineer called back with a fix I installed and they upgraded the units going forward. First rate company

Not saying Apenglow arent first rate - but by the time you buy the kit and ship it to the other side of the world it really does double the price.

Do you have a photo of the upgrade?

[geoffr]

I bought one of the new Alpenglow lights as we wanted another one. I then took it apart to figure out the parts they are using and then bought the parts from an electronics distributor and retrofitted the other Alpenglow we have.

By doing it this way you can "tweak" the light to more of what you want (eg the color index and brightness), but still following their good design.

The internals are as follows:

• LM2940T (Creates fixed voltage so can create known current)
• 2x Cree 1304C
• 150ohm inline for Red LEDs
• 1Kohm for Low Setting on Red LEDs
• 2x 0.56ohm for Cree (one each inline)
• 5.7 ohm for Low level on Cree.
• Unknown Red LED strip - I just bought on and cut to the correct size for the brightness I wanted.

I did change some of the R's on my design to get the levels I wanted.

[BigAl.NZ]

Originally Posted by geoffr

I bought one of the new Alpenglow lights as we wanted another one. I then took it apart to figure out the parts they are using and then bought the parts from an electronics distributor and retrofitted the other Alpenglow we have.

By doing it this way you can "tweak" the light to more of what you want (eg the color index and brightness), but still following their good design.

The internals are as follows:

• LM2940T (Creates fixed voltage so can create known current)
• 2x Cree 1304C
• 150ohm inline for Red LEDs
• 1Kohm for Low Setting on Red LEDs
• 2x 0.56ohm for Cree (one each inline)
• 5.7 ohm for Low level on Cree.
• Unknown Red LED strip - I just bought on and cut to the correct size for the brightness I wanted.

I did change some of the R's on my design to get the levels I wanted.

Thanks. Reading up the specs now.

Do you know if the output of the LM2940T is 5v or 12v or? That chip has a dash after it i.e. LM2940T-5 is 5v out.

Are the CREEs wired in series or parallel?

What did they mount the CREEs on - anything special for power management?

Don't suppose any pictures?

Thanks again.

[CarinaPDX]

I have had Alpenglow lamps on Carina for more than 40 years. Initially they had two CFL bulbs, one 9W warm white and one 7W with a red coating. I have always liked the look of the lamp and the wide and even dispersion of the light. The red coating turns out not to have been durable, and not very efficient, so when Alpenglow came out with red LEDs I bought their upgrade kits, for about $16 IIRC. It was a simple design with limiting resistors and has worked well. When Alpenglow came out with their white LED I looked into an upgrade but decided not to use their approach. IIRC they use two Cree LEDs, which creates small and intense sources of light. I saw them on a friend's boat and did not care for the result (he doesn't like them either). And for far less than $75 each I was confident I could come up with a better solution. I have been using my solution for several years now and am very happy with the result. YMMV.

I started by selecting a COB LED strip (3000°K) and a high quality driver. The advantage of a COB strip is that the light is created by multiple LEDs in a row and encapsulated in a plastic that acts to disperse the light such that it appears as a bar of light, similar to a small straight fluorescent tube. I find the result more pleasing than both the Alpenglow LED and CFL solutions. The COB is very inexpensive, less than $5 IIRC. I am driving the LEDs with a high end (~$20), US-made, constant current dimmable driver that matches the maximum power of the COB. The output is set using two switched resistors (in the dimmer input). As it turns out I have chosen half power as the high output and quarter power for low, which is just my personal preference but also should result in a long life. I have mounted the COB on an aluminum heat sink with thermal paste, in turn attached to the aluminum backing plate, and the driver is also attached to the plate with thermally conductive double-sided adhesive tape. I suspect the thermal precautions are a bit of overkill but good practice nonetheless. I have used the existing switches, the small one for the (retained) red LED high/off/low, and the larger one for the white high/off/low.

I had intended on documenting this so if there is any interest I can provide photos, specs, and sources. The schematics are very simple as there is only the COB LED, driver, resistors, and switches; I can put together a drawing if desired.

Greg

[BigAl.NZ]

Originally Posted by CarinaPDX

I have had Alpenglow lamps on Carina for more than 40 years. Initially they had two CFL bulbs, one 9W warm white and one 7W with a red coating. I have always liked the look of the lamp and the wide and even dispersion of the light. The red coating turns out not to have been durable, and not very efficient, so when Alpenglow came out with red LEDs I bought their upgrade kits, for about $16 IIRC. It was a simple design with limiting resistors and has worked well. When Alpenglow came out with their white LED I looked into an upgrade but decided not to use their approach. IIRC they use two Cree LEDs, which creates small and intense sources of light. I saw them on a friend's boat and did not care for the result (he doesn't like them either). And for far less than $75 each I was confident I could come up with a better solution. I have been using my solution for several years now and am very happy with the result. YMMV.

I started by selecting a COB LED strip (3000°K) and a high quality driver. The advantage of a COB strip is that the light is created by multiple LEDs in a row and encapsulated in a plastic that acts to disperse the light such that it appears as a bar of light, similar to a small straight fluorescent tube. I find the result more pleasing than both the Alpenglow LED and CFL solutions. The COB is very inexpensive, less than $5 IIRC. I am driving the LEDs with a high end (~$20), US-made, constant current dimmable driver that matches the maximum power of the COB. The output is set using two switched resistors (in the dimmer input). As it turns out I have chosen half power as the high output and quarter power for low, which is just my personal preference but also should result in a long life. I have mounted the COB on an aluminum heat sink with thermal paste, in turn attached to the aluminum backing plate, and the driver is also attached to the plate with thermally conductive double-sided adhesive tape. I suspect the thermal precautions are a bit of overkill but good practice nonetheless. I have used the existing switches, the small one for the (retained) red LED high/off/low, and the larger one for the white high/off/low.

I had intended on documenting this so if there is any interest I can provide photos, specs, and sources. The schematics are very simple as there is only the COB LED, driver, resistors, and switches; I can put together a drawing if desired.

Greg

Thanks Greg - that is most helpful. Yes I saw those CREE are just two high intensity LED's and wondered if the diffuser would get around the appearance of spot light - but from your comments it appears not.

Some photos and part numbers would be most helpful. Thanks!

[geoffr]

Took me a bit, but here is an album of photos showing the Alpen Glow LED version and my rework of an older one.

https://www.cruisersforum.com/forums...lbums5951.html

[geoffr]

Originally Posted by BigAl.NZ

Thanks. Reading up the specs now.

Do you know if the output of the LM2940T is 5v or 12v or? That chip has a dash after it i.e. LM2940T-5 is 5v out.

Are the CREEs wired in series or parallel?

What did they mount the CREEs on - anything special for power management?

Don't suppose any pictures?

Thanks again.

The LM2940T is a 10V version.
I mounted the CREEs with a thermal tape.

Here are some full parts:

• Cree: http://www.mouser.com/search/Product...A13040C00A40E8
• Cree: http://www.mouser.com/search/Product...A13040C00A40E8
• Thermal Tape: http://www.mouser.com/search/Product...dBP100%2d01100
• Red LEDs: http://www.mouser.com/search/Product...8%2dOVQ12S30R7

[BigAl.NZ]

Originally Posted by geoffr

The LM2940T is a 10V version.
I mounted the CREEs with a thermal tape.

Here are some full parts:

• Cree: http://www.mouser.com/search/Product...A13040C00A40E8
• Cree: http://www.mouser.com/search/Product...A13040C00A40E8
• Thermal Tape: http://www.mouser.com/search/Product...dBP100%2d01100
• Red LEDs: http://www.mouser.com/search/Product...8%2dOVQ12S30R7

Thats awsome. Thank you.

[CarinaPDX]

I took a few pictures. The first is a side-by-side comparison of my LED conversion (left) with the original CFL (right), both on LOW.

This is a shot of the interior. You might notice a pair of trimpots in the lower right; for testing I used these instead of fixed resistors.

In this photo you can see the heat sink, with the drilled and tapped holes for attaching the COB to the heat sink, and the heat sink to the back plate. Also the regulator with the blue double-sided thermal tape is shown, and at the top is a M/F pair of 5.5mm barrel connectors on pigtails. I use them for the power input so it is easy to mount/unmount from the overhead. I had to grind flat surfaces on two sides of the connectors to make it narrow enough to fit on top of the lamp.


This is the COB I used: https://www.dx.com/p/6958-diy-10w-30...v-2019794.html

The regulator is the 700mA version (compared to the COB 720mA rating): https://www.ledsupply.com/led-driver...-dc-led-driver . After putting it down on the back plate with the thermal tape I put a filet of adhesive sealant around it to help hold it in place (the adhesive on the thermal tape isn't very strong).

The heat sink is 150mm x 20mm x 6mm, from an AliExpress.com vendor (search and you will find many vendors - just look at shipping as well as price as these are cheap). Be sure to use thermal paste when assembling COB to heat sink.

You can order 20k trimpots if you want to experiment with the light outputs. I am now using 10kΩ resistors (half power) for HIGH and 5KΩ resistors (quarter power) for LOW. It is also possible to use commercial LED dimmer controls as input instead of resistors, or simply buy a nice 20k pot (or two) with knob and mount it on the case for easy adjustment.

The switch used is a two pole/double throw rocker switch (the original). One pole is used for switching the power (ON-OFF-ON) while the other selects the appropriate resistor.

The red LED board is the conversion from Alpenglow.

I think that's it but ask if I left anything out.

Greg

[BigAl.NZ]

Thats a nice job Greg, and I do tend to agree about the two spots when using the Cree LED's. That controller will add quite a bit to cost for each light though.

Is that controller to adjust brightness?

I also noticed that they called it 3000K warm white - but it still looks like 5000k+ - what do you think as sometimes photos are not accurate.

[CarinaPDX]

The LED is possibly a little higher temp than 3000°K but probably not more than 3500°K. It is a very comfortable white. Personally I have come to prefer it to the very yellowish 2700°K CFLs. When I buy LED flashlights I buy neutral white (usually around 5000°k to 5500°K) instead of the more common 6500°K cool white. These COBs are definitely between 2700°K and 5000°K, and not 5k.

You certainly do not need to buy a controller like this. OTOH you may want to avoid the ultra-cheap ones too. This is a constant-current driver with a very flexible dimming input. The dimming input can be just a potentiometer (variable resistor), a 0-10VDC input (used by some dimmer switches), and PWM (pulse width modulated) input (used by other dimmers), and all will result in a clean, constant current output at the appropriate dim level. This driver is also very efficient (90%). It is easy to mate with a COB without knowing the internal series resistors (although that can be worked out).

The easiest approach for a quick and quality driver is to buy a constant-current driver. If you want two light levels then it will have to have some allowance for dimming but it need not be variable. The simplest design would be a basic DC-DC power supply with additional limiting resistors to deliver the correct amount of current for each light level. You could try to work out the internal resistance and calculate the effect of additional resistance or just try with different values (being careful to not overdrive the LED). This can be very inexpensive and effective. Do watch for the efficiencies.

Greg