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    • February 24, 2020 11:28 AM EST
    • Dave,

      Something is really wrong with that light.  No way those resistors should get that hot.  If your readings are correct, then the current is 3.11 amps and 9.99 watts on those resisters!  

    • February 24, 2020 1:00 AM EST
    • As Greg has said  they are composed of 10 LEDs in parallel (the little dark strips are the LEDs).

      Here is how I would do it; cut all the El Cheapo crap out and bin it then use an LED  calculator to figure out the value of a current limiting resistor using the voltage that will be connected  and 10 LEDs in parallel

      From a calculator using 6V supply, 3.6V LED voltage (white LED supplied by calculator), 30mA ( just plucked it out of thin air), 10 LEDs in parallel gives a resistor value of  8 ohms. (8.2 ohms closest value that is readily available)

      Link to calculator I used to get those figures.  https://www.easycalculation.com/physics/electromagnetism/led-parallel-resistance.php

      When you say 6 strips are you talking about connecting 6 LEDs strips in parallel that is one hell of a lot of LEDs?  I have one of these in my shed and it lights it up like Vegas.

    • February 23, 2020 11:18 PM EST
    • OK ..Here is second try...

      First is VDC straight across the leads off 4 fresh re-charged Ni-Mh batteries.  5.75 VDC

      And then with LEDs lighted VDC thru the Resistors...  3.211 VDC.

      BTW:   The resistors got HOT... after only 3-4 min of the LEDs on, they got so hot that that they blistered my finger when I touched them...

      Just seems that they were using up a lot of energy as heat... is that normal?

       

      Hope that this gives enough info to help.

       

      Dave

    • February 23, 2020 10:25 PM EST
    • Oh Oh.,,,  See why I ask before I let the magic smoke out?

       

      OK.. I get right on it and get that measurement.  DC VOLTAGE, using the same test setup..

       

      Dave

       

    • February 23, 2020 10:14 PM EST
    •  Dave,

      What Greg was asking is for a DC  VOLTAGE reading across the resistors.  With that reading and knowing the resister value it is an easy ohms law calculation to get the actual current draw.  Where the heck is Greg !

    • February 23, 2020 8:02 PM EST
    • Back home and at it....

      Took the LED strips off the mount,   And sure enough they are wired in Parallel.

      Here is a composite of the 4 end wiring of the LEDs.  Maybe the printouts on the board ends will mean something. L to R of the LED ends.

      Made the R readings, I don't know if my meter is accurate enough, it's the best one I have.

      1st:  Batteries in, no power to the LEDs.  1.1 Ohms

      2nd: Batteries In, LEDs Lit.  7.55 M Ohms.

       

      I hope that this helps to come up with an answer...   If I need to do or provide anything else,  just ask....

      Dave

       

       

       

    • February 23, 2020 5:46 PM EST
    • Dave,

      Batteries in, power on.

    • February 23, 2020 4:11 PM EST
    • Thanks Greg....When I get home today I'll measure the R on the resistors.....

       

      My ignorance here.... When I measure across, Do I have the batteries in, and or the LED's burning?

       

      Dave

    • February 23, 2020 12:57 PM EST
    • The key here is to understand why 2 red wires between the modules, and what the resistance is.

       

      Those are 6.2 ohm resistors, and 6 in parallel (to handle the current) is 1/6 of 6.2 ohms, i.e. 1.03 ohms... just enough to limit the current a bit...

       

      Most likely each of those arrays are leds in parallel, so nominally they would take 3.6 volts each, thus the 6v supply.

       

      at so low a resistance, the numbers are pretty impossible to work without knowing the voltage drop across the resistors or the leds.

       

      if you can measure the voltage across the resistors with an accurate meter, we can calculate the current drawn and then proceed.

       

      The other way is to get a large 1 watt 1 ohm resistor, cannot think that you need anything higher wattage.

       

      Greg

    • February 22, 2020 11:12 PM EST
    • OK guys...  ISO some help to re-wire three of these HF battery lights...  into A strip of 6 of the LED strips wired end to end, [ linear strip ].

      Powered by 4ea AAA batteries  ( comes with the worlds worst cheap batteries).

      Opening it up shows this:

      and inside...

      And the bottom of the switch circuit board...

      So I traced out a schematic ...... pertty simple,,,,but I don't understand how to cut out the resistors or add enough, or what happens to put the six light strips in a long row.

      I believe the 2 Led strips are wired in parallel ....

      I have 3 ea. 4 up AA battery cases [6VDC] output, that matches the 6VDC of the original light case,  to use as a larger Mhr power source.

       

      So could someone help me out in what I need as a wiring diagram, and what to do about the resistors in each of the original circuits , or how to wire up the lights...

      I have lots of resistors and stuff to get it wired up, just don't know what to do, to not burn the LED's up..

    • February 14, 2020 2:22 AM EST
    • John Caughey said:

      Since most switches are momentary, I think you'd need another switch (dpdt) controlled by the turnout motor to activate a different power supply for the LEDs, which are polarity sensitive.

      I did it on my old HO layout I used a microswitch to turn on one LED and the other off on a mimic panel so I could see the direction the point (turnout for the US folks) was set to.

      The switch was a NO/NC switch that activated depending on the point arm position.

      Would be very easy to do, so easy in fact that I am planning on using it on new my G layout but this time switching signal lights as well.

      No real need to involve a point motor except for positioning the "throw bar?".

      Power supply under cover LEDs wherever and switch in a water resistant cover.

    • February 13, 2020 3:55 PM EST
    • In addition to what John said, your switch motor will draw more than the current capacity of the LED, and then it changes from an LED to a DED .... or worse an open circuit..

       

       

       

    • February 11, 2020 9:13 AM EST
    • Since most switches are momentary, I think you'd need another switch (dpdt) controlled by the turnout motor to activate a different power supply for the LEDs, which are polarity sensitive.

    • February 10, 2020 4:48 PM EST
    • Just for my own curiosity could an LED (light emitting diode) be used and have the added benefit of "showing" the switch position?

    • January 23, 2020 5:59 PM EST
    • Thank's Greg , I knew I could count on you guy's. I hope I learn enough to be able to help someone out too. 

    • January 23, 2020 4:54 PM EST
    • The 1N4xxx series will be fine, not signal diodes or zeners.

       

      Pick the amperage you need, I would guess 1 amp would be enough, but maybe buy the 3 amp ones just to be sure.

       

      Greg

    • January 22, 2020 5:50 PM EST
    • Good afternoon everyone :

      I'm hoping I can get some wiring help. I want to install motor units on my piko switches . I made my own control panel with momentary toggle switches to control them. I found wiring diagrams that help me but I keep seeing references to "real diodes " . Can someone tell me what size I need and how to install them . I have a USA TRAINS train power 10 and I don't know if that makes a difference. Also, where I can get them. I'm new to the hobby and you guy's have already helped me twice and I'm hoping you will do it again. Another diagram would be really helpful too.

      Thank's

      Bob      

    • January 22, 2020 5:50 PM EST
    • Good afternoon everyone :

      I'm hoping I can get some wiring help. I want to install motor units on my piko switches . I made my own control panel with momentary toggle switches to control them. I found wiring diagrams that help me but I keep seeing references to "real diodes " . Can someone tell me what size I need and how to install them . I have a USA TRAINS train power 10 and I don't know if that makes a difference. Also, where I can get them. I'm new to the hobby and you guy's have already helped me twice and I'm hoping you will do it again. Another diagram would be really helpful too.

      Thank's

      Bob