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My wife acquired second-hand model houses with lights and an single adapter which had 5x DC power outputs, one for each house to light up. She was using it and the adapter started to smoke and catch of fire... Thankfully she was quick in responding to the situation.

This is the point where I learned about all this, and found the adapter appears to be a hacked replacement... the 5x DC connectors were cut and spliced onto a different adapter; the ground wire not connected and just wrapped in tape.

I now have to find a proper replacement. The houses have lights which are rated 6V 5W 1AMP on each house. The fire-and-melt-adapter was 19.5V 35W .8AMP.

I have an adapter which is 19V 90W 4.74AMP from a laptop. I have been trying to understand how to calculate if the 19V 90W 4.74AMP adapter would do? I believe that the voltage 19/5 lights would produce 3.8V to each bulb and the 90W capacity should be more than enough to prevent melt-down.

Would this work? If not, could someone help me understand how to calculate a safe adapter with the correct Volt/Amp/Watt, that would power 5 of these houses, that I can use, that will not set the house on fire?

Summary succinct question: Given 5 lights in series of 6V/5W/1A, calculate the V/W/A adapter needed to power safely

Chris
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  • Please produce a schematic showing any resistors in series with the LEDs. – Andy aka Oct 20 '23 at 20:51
  • Just to preface, I am an electric circuit newb, with 0 experience. So was the guy who rigged this thing up, that could have burned down the wifes she-shed. I don't want to be that guy. Andy: There are no resistors, it is a power supply and lightbulbs. JYelton: No, they talk about matching a single device, while the wifes houses are 5 separate devices. – Chris Oct 20 '23 at 22:14
  • A couple of thoughts: 1) The request for a schematic is still potentially the most useful. We (and you) need to know how the bulbs are wired. 2) The question I linked explains how current is determined by the load and is generally very valuable for (as you said) newbs. Since it should be obvious that a 19V supply would burn out 6V lights, there must have been some lights wired in series or with resistors or something. If you can reverse-engineer the lights/houses and provide a diagram, it will be instrumental in providing a good answer. – JYelton Oct 20 '23 at 22:26
  • I have no way of producing a schematic if I have 0 electronic experience. I would assume because of what I read in the other question, that is a device (house with a light) says it needs 6V, 5Watt and 1 AMP, that the internal workings would not matter as long as the power provided is the power provided - otherwise why put it there if it is useless? So the real concern is: if there are 5 houses in series which each require that above, do I need a 65 volt (30 volt) adapter which is 55 (25 watts) and 1*5 (5 amps)? Or how do I calc it. What the house does with the 6V it gets should not matter. – Chris Oct 21 '23 at 02:09
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    to answer the question in the last comment above mine; no, you keep adding where you shouldn't (W=VA), (30v5a=150w). you can use a 5A 6V supply and run them in parallel, or a 1A 30V supply and run them in series. Your supply should actually have more current/amps than needed (can't have too many there), it's not good to "redline" them. You can safely try your laptop adapter to run them in series; it might not work at all because the initial turn-on cold resistance immediately triggers the short circuit protection in the laptop supply, or, it starts fine and runs them at half brightness. – dandavis Oct 21 '23 at 06:46
  • Thank you for the answer how I hoped, so you add the V but not the A if in parallel, okay got it. So the laptop has half the voltage needed but more than enough W/A so no risk of burning if it works, just it will not be super bright. Cheers Dan, much appreciated. It is worth mutilating the adapter then to try. – Chris Oct 24 '23 at 21:37

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