A really cheap 12volts..

[Morgen 3Eman]

Hi Folks,

I know some of you use DC-DC convertor for lighting power. 


My 48v-12v DC-DC convertor apparently didn't like 58 volts, and quit working.  I used it to run lighting circuits on my Morgen, maybe an amp and half max.   While I was whining to myself about wasting $30, it occurred to me that the little 100v-240v input power supplies used with laptops were actually switching power supplies that used a full wave bridge rectifier at the input, and would laugh to being subjected to mere a 58 VDC input.   

Anyway, I found a junk shop (Salvation army) that had a 12v 4 amp output  power supply, and wired it in last night.  It works like a charm, and only cost $4 US.  And I made a donation to Salvation Army to fund their good work .



TTFN
Dennis

[skylinenitro]

Are you talking about the laptop power bricks?  the ones that have a 120v AC plug on one end and some 12-30v dc plug with a tip on the other end?

[Morgen 3Eman]

Well, yes and no.

I am specifically not talking about heavy little boxes that have only 110 VAC or 240VAC as an input or a voltage selector switch on them.  If you put a transformer based power supply across a battery, you will quickly have something that will never work again.  And that could include the battery.  (I had a lead-acid battery explode in one of my Mini Coopers)

What I am talking about is the light weight brick like boxes that allow 100 VAC to 240VAC operation without any switch for selecting the input.  On ones I am using, they are labeled " "Input 100-240V  ( ) Amps 50-60Hz", and that is followed by whatever the output voltage and current might be. 

Any easy test if you have an Ohmmeter is to read what the input resistance is.  If it is on the order of 10s of Ohms, it has a transformer input, and should not be used. 

I am currently expanding on my usage of switching power supplies.  I found an electronic junk store that had a switching supply that had two 3.6VDC 1Amp outputs,only weighed 4 ounces, and had a $3 price tag.  I also found some 1 watt LEDs, that need 3.6Volts.  They are destined to become the headlights on my Morgen 3Ewheeler.  Now I have to fabricate a suitable housing and then mount them. 

TTFN,
Dennis