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[Fastfaz]

  Greetings everyone,
           I have to overcome the following problem with the working lights on the logging tug I am scratch building and would like to ask if anyone out there has tried this method out. The mast has a square frame at the top ( similar to a Rugby goal post frame) like a letter H and in total there are 17 lights as follows- 3 running lights on the centre pole, the bottom cross rail has 3 deck lights and 1 running light at each end so 8 lights on that rail, the top cross rail which is parallel with the bottom rail has 2 deck lights and 1 running light at each end so 6 lights on that rail. I like to run all my LED's from the main 12 volt battery and usually run a pair of wires from each individual LED soldering in a resistor to the red wire to reduce the 12 volts down to 3.2 so the LED works without burning out. Unfortunately due to the large amount of lights this would mean 34 individual wires coming down the mast as its impossible to get them inside the tubing due to both the  H shape layout and the amount of wires. What I am going to try out is to use my normal thin cable from each LED soldered to a single larger cable ( 1 red , black) with the resistor soldered in place, which I can then hide behind the main centre tube of the mast and down to the power supply. The problem I see arising is that the LED's will be on a kind of ring main as in household sockets so its an experiment which I am not sure will work (i.e. 4 LED's in a line = 4 x LED's x 3.2 volts = 12.8 volts, there are 17 LED's to connect up). I have never tried this but have done 3 LED's in line successfully using a smaller resistor. I really just want to reduce the amount of wiring running down the mast to a minimum, so if anyone has any ideas/suggestions I would really appreciate it.


             Thanks in anticipation,
                  Regards, Pete.

[minimariner]

     


                             Can you post photo`s of the mast and tube ID sizes, and how you are mounting the LED`s.

[Fastfaz]

Hi,
   I am useless at posting photos on the forum sorry but I'll try to answer your question. The Led's will be glued into the backs and underneath of each light which my normal way of fixing them, mast is made from 4mm brass tubing and the vote is too small to take more than 1 pair of wires. If you pm me a message with an email address I can email photos as I don't have any problems doing that. Thanks for looking. I have been thinking that I can reduce the number of wires by fitting 4 Let's in a line so we will see.
     Regards, Pete

[derekwarner]

If you have photos, send them to me via my landline e-mail address & I'll post them in your thread


You will find the address in my profile by clicking my name to the left of this posting


Derek

[HMS Invisible]

  Greetings everyone,
           I have to overcome the following problem with the working lights on the logging tug I am scratch building and would like to ask if anyone out there has tried this method out. The mast has a square frame at the top ( similar to a Rugby goal post frame) like a letter H and in total there are 17 lights as follows- 3 running lights on the centre pole...

...The problem I see arising is that the LED's will be on a kind of ring main as in household sockets so its an experiment which I am not sure will work (i.e. 4 LED's in a line = 4 x LED's x 3.2 volts = 12.8 volts, there are 17 LED's to connect up). I have never tried this but have done 3 LED's in line successfully using a smaller resistor. I really just want to reduce the amount of wiring running down the mast to a minimum, so if anyone has any ideas/suggestions I would really appreciate it.


             Thanks in anticipation,
                  Regards, Pete.

Forget any notion of 4 white or blue leds in series unless you have a 4s Lipo battery.

You'll find that a block of eighteen matched leds in 3s6p format will be equal brightness with the total current equally divided by six.
Twelve-volt cob leds and old 12v ac/dc MR11 lamps were wired as such, so you have one resistor or constant current  driver to hook up to these two wires.
Does enameled copper wire or 0.4mm dia 10/0.1 pvc insulated wire help?

And take a photo with your phone then view it in the gallery or photos utility. You might see an icon that indicates an edit menu where you can crop, rotate or reduce the filesize to below 5Mb at which point both the "attachment" or  "Add image..." options will do the rest.

[Ralph]

If your mast is brass, could you use it as one of your conductors?  I did that many years ago, running a common negative down the mast from all the lights cut down the wiring by half.  That was with grain of wheat bulbs rather than LEDs but I think it should still work.


Ralph

[Fastfaz]

 Hi All,
     Thanks for the responses (much appreciated) definitely food for thought and good ideas. Mike you could of written in Chinese and I wouldn't have understood how to go forward, give me chunk of timber and I can work small miracles but when it comes to electrics I'm in primary school. Oh how I wish you could supply more FR40's, I used a lot of them and they were so easy to work with and reliable and, in my opinion, the best available  from the market place. I definitely won't give up on this as I am sure that, with the help of the Genius's on the forum, I will find a way to resolve this without having a wiring loom that is thicker than the mast. I like the idea of using the mast as the negative (halving the amount of cables) but soldering is not one of my better skills, however I know a man who can.
     Thanks everyone for all your help its given me lots of ideas.
              Cheers, Pete.
                         

[HMS Invisible]

You wire eighteen 3.3 volt leds into one big 10 volt one.
They are all identical white leds are they not?

Then instead of six resistors you need one resistor because the led current in six parallel branches will balance equally regardless of cable runs.

If everyone could see and count the number of mains transformers around the house they might be surprised. All you need for your led task is enameled copper of a human hair's width running outside a mast.
You are surrounded by this type of wire even in 2024.

[Fastfaz]

 Hi Michael,
     Thank you for your, in my opinion, brilliant knowledge of electrics and help with my problem. Derek Warner has said he would add the photos I have taken to the post (I have emailed him and waiting a reply) which shows the light layout (apart from the 3 running lights on the central mast which I did not put in the photos), this shows the actual mast lights in position. All of the deck lights and the 3 main mast running lights are white, however the 4 running lights on the cross rails are red. I have not had a problem using the same resistor on the white and red LED's although I know that each different colour of LED needs a different rate of resistor so I don't see a problem there, where would I get a 10 volt one. As there are 17 LED's would that still work instead of being 18 LED's? I normally source all my LED's, cables etc from Component shop but I have not looked to see if the do a 10 volt LED so would really appreciate your help in sourcing them. Giving this some thought I could always have the 10 volt Led hidden in the hull underneath the wheelhouse allowing the full 18 LED's. what do you think?
     Re the FR40's do you still do them or (knowing you) a better version?
         Thank you again for your replies, your knowledge and help is very much appreciated.
                Kind Regards, Pete.

[HMS Invisible]

It's 'start again all over again' on the leds front and forget 18.  That is more like my understanding of running lights but your opener didn't account for the lower voltages of red, orange, yellow and green. The good side is the colours start to conduct much lower in voltage than white so you can stack more to work at 12v.

Current regulation for leds
I know it's not your thing but you can buy a ten-pack of TL431 from Ebay to wire them as 10mA constant current sources for LED strings.
You can stack leds in series as long as you leave 2.5 volt drop for the TL431. You can also make constant current circuits from discrete components. These are cheaper to make at 5p per series branch but that could drive 11 volt of series connected leds off 12v.

On the speed control front, these are the two Chinese escs that passed muster.
https://www.ebay.co.uk/itm/285626492724 is truly a very high power single esc with no bad quirks. They use 24 drive transistors in an H-bridge where the resistance of six equates to that of two inches of 14 awg copper cable.
It's switching bec stays efficient at high voltage. You need to keep battery cable short as its motor drive switches at 8kHz.
Second is a dual esc https://www.ebay.co.uk/itm/195412895928
It requires you to add a solder blob to make it work as two separate escs without mixing.
You are supplied with 18awg battery wire & JST and 20awg motor wires terminated in red JST connectors. The auction photos are out of date. I've replaced their 7805 bec chips with a tiny 3 amp ubec module so the esc can run four 555 motors at 6s lipo. The two caps needed changed.

I've yet to get a higher current one in the mail. https://www.ebay.co.uk/itm/235288992272
I can't comment until I've tried one.
 

[Umi_Ryuzuki]

I ground the mast, and run three wires. Running lights, Towing Lights, and Deck Lamps.
Seventeen total lamps(LEDs) - 12 volts DC main power is run to the mast. 
Each wire(circuit) is split off as needed for each lamp. Each LED has it's own resister, disguised as a plug connector.

[Fastfaz]

Hi Umi,
          Your photos are almost exactly like my planned mast (apart from a red running light at the end of each of the cross rails which I could use a white LED and paint Tamiya clear red)) and I like the way that you have done it, very clever and seems doable for dumbo's like me.
         Michael, thanks again for the help I am going to have to digest your info gradually it's way above my pay grade.
                      Thanks to you all for the replies.


                                 Cheers, Pete.

[Fastfaz]

Hi again Umi,
                    Could you possibly post a wiring diagram of how you did your lights on the mast please.
                            Cheers, Pete.

[HMS Invisible]

....
         Michael, thanks again for the help I am going to have to digest your info gradually it's way above my pay grade.
                      Thanks to you all for the replies.


                                 Cheers, Pete.

  It's easier to digest with diagrams, photos & links. These won't be forthcoming if I'm replying on a smartphone and still learning to use its image editor which won't let me manipulate a gif image off the Internet. 

 Resistor values off a 12 volt supply don't change much with the colours being 2 to 4 volts. However the resistors will get HOT, HOT, HOT at 10mA. So if you want bright  leds with individual resistors starting point is drop the voltage.
One way might be all tinted white leds without resistor & run from a separate 1s Lipo. It requires further checking and suggestions!
e.g. discarded vape lipo & rob the USB lipo charger from a Poundland pen powerbank.

[Umi_Ryuzuki]

Hi again Umi,
                    Could you possibly post a wiring diagram of how you did your lights on the mast please.
                            Cheers, Pete.

There isn't any heat, each LED doesn't draw that much power.
Each circuit is run in Parallel, so full power through the wiring and a resistor at each LED.
So the wiring diagram would be simple for one LED, and similar for multiple LED.Black or ground to  the negative terminal of the battery, and up through the mast.RED is the switched side of the circuit for one or more LED

[Colin Bishop]

Grain of Rice 12v  incandescent bulbs run on 6v could be a viable alternative. The lower voltage doesn't stress them and in reality ship navigation lights are not actually very bright.

Colin

[HMS Invisible]

There isn't any heat, each LED doesn't draw that much power.
Each circuit is run in Parallel, so full power through the wiring and a resistor at each LED.
So the wiring diagram would be simple for one LED, and similar for multiple LED.Black or ground to  the negative terminal of the battery, and up through the mast.RED is the switched side of the circuit for one or more LED

You are replying to Peter but I made a comment on resistor heat immediately prior.
My point is led current, therefore led brightness, is limited by a 12 volt bias resistor getting hot at 10mA. In the past you mentioned using the smaller resistors where the carbon film version is rated at at 1/8th Watt & metal film 1/4 Watt mounted at 0.3" on fibreglass circuit board. Ten volts at 10mA is 0.1 Watt which, over the tiny resistor's surface area is hot with capital letters. In the absence of a flir camera the tip of a tongue would say so.
A rule of thumb in circuit design is keep the power dissipation of resistors below half their rating and that's where circuit board copper can conduct heat away.
 Then again, it's personal preference because the effect is to shorten life to tens of thousands of hours.

[Graham.W]

Just as a note to this as I have a) a tug boat and b) LED lamps on it, haha, I thought I'd just say what I did, to see if anything is useful!

To wire the LEDS I find an old inductor, or you could just buy some thin enamelled wire, perhaps 0.4mm or something, as this gives a very thin, insulated wire, and to solder just scrape off the coating at the tip and it bends and solders nicely. These I then arrange down the mast to some type of multi-plug of 0.1in pitch or similar.

But here they really just need wiring into a little Veroboard in the cabin, using resistors or current sources to get the right brightness. You can also use diodes and jumpers for different lamp settings, or perhaps a DIP switch array, that type of thing.

LEDs like current, after all they are diodes: not voltage. So mine I run from 12V, and use a mix of current sources or resistors. If going for current sources, use a decent 2 transistor one IME, as they work better.

With these you can put LEDs in series, of the same colour. If you have many lamps, perhaps consifer using 24V into the cabin. How to get 24V? Well, eBay sell various DC boost circuits and you can dial in the step up, or step down voltage required.

Red and green lamps IME need vastly differing currents, it all depends on LED type and location, in my models I needed to tweak the currents until everything looked right. I'd go for Ultra-bright LEDs, and use low currents as this is easier and uses less power. Even on 1mA, some LEDs are very bright now.

White LEDs seems to drop the most voltage, about 3V IIRC, so you'll get 2-3 in a 12V string with a resistor or current source.
For a fishing boat I just did, that has a 6V motive battery for good scale speed, I used a DC-DC boost circuit to provide 12.0V to the cabin. This stable voltage could then be used with simple resistors to the LEDs, in both mast and cabin. This type of thing I'd recommend as it looks great, and at home you can use a 12V wall PSU to light the lamps up on the sideboard (see avatar).

Also with a stable lighting voltage, the lights don't flicker. Of course on some old fishing boats, they might actually flicker... but mine don't LOL.

[HMS Invisible]

Graham, I was going to wire up a tiny 3-4 volt buck regulator to show Fastfaz.