$13 Auxiliary Project Power Supply

[FourLoti]

Hi:

This may or may not be interesting or applicable to many others, but it was a fun, cheap project so I'll share it.

After two weeks of having to reposition cars and trip over jumper cables every time I needed to trace a circuit or test a relay, etc., I decided it was time to buy my car its first big homecoming present (and spiff up the engine bay a bit,) by getting a shiny new battery. But just in time, before shelling out $170+ it occurred to me that there's a non-zero chance the warranty would run out before this car ever needs a self-contained power source. Further, there are tons of more critical things I need to buy just now.

So after some thought, it was Amazon to the rescue with this nifty 12v, 5A, $12.99 power supply.  https://www.amazon.com/ALITOVE-Universal-Regulated-Switching-Transformer/dp/B078RY6YY3/ref=asc_df_B078RY6YY3/?tag=hyprod-20&linkCode=df0&hvadid=241973970700&hvpos=&hvnetw=g&hvrand=9820710088905904222&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9014979&hvtargid=pla-419329457436&th=1

Note that I could have gone "big" for five more dollars at twice the wattage, but I felt compelled to honor the Lotus & Lucas tradition of barely adequate design work to save a few bucks   But, unlike a battery, this thing has overload and short circuit protection! Regardless, I did cover up the "now live" positive battery clamp just in case.

But I believe 60W will handle everything I will need to test, with the exception of when I need to crank it over again, and for that the old jumper cables will be just fine. 

Cheers,

Ron

[dakazman]

  You are definitely testing that to the limit!
  I don’t expect it to last long in a wet climate.  I love it when I’m wrong though.
Dakazman

[jbcollier]

I just keep an old battery around on a trickle charger to do that sort of work.  Batteries that no longer happily crank a car over at -30 still have lots of life in them for this sort of work.

[FourLoti]

Thanks for the input. As I said, this may not be of interest/value to many other members. Just something that works for me that I wanted to share.

I wish I had a spare battery and/or other cars that could be donors, but I don't, and truth be told, transplanting a hunk of lead just to power my test lamp is not that convenient. I'm a couple of weeks into exploring a car that sat for 20 years, and some days I work on the mechanicals, and others, on the electrics. Case in point, today I degreased, re-greased and re-installed the window mechanisms. It was really convenient to just plug them in and check the switch operation thanks to the power supply.

I don't expect to be using the standby power very often, but for the price it seemed worth having. Not sure what the wet climate comment was about as this is an indoors Lotus "monument" for the foreseeable future.

Ron

[dakazman]

  Ron, Now I understand for what and when you’re using it.
 I’m using an old batter  to now just for testing everything. I just might pick one up myself since I’m tired of buying batteries for 8 vehicles every four years.
Thanks
Dakazman

[jbcollier]

I use good quality, trickle chargers on my batteries that don’t see regular use.  One battery lasted 14 years.

[dakazman]

  Dang, with is heat 4-6 years is considered good.
 Dakazman

[GavinT]

That's is a good idea but I'd be nervous about the input AC terminals being exposed like that, particularly if under the dash in the Lotus position.
I use an old power supply from a long dead printer or something – looks a bit like this one. The input side mains plug is there and breaking out of the 12v wiring is needed - no biggie.

https://arcus-www.amazon.com.au/Adapter-100-220V-Switching-Monitor-Security/dp/B07MM14TQC/ref=sr_1_6?keywords=12v%2Bpower%2Bsupply&qid=1684381474&sr=8-6&th=1

[FourLoti]

Thanks Gavin - that one looks good.

But just to be clear, I'm not using mine as a test tool that I take around to various parts of the car. It's stationery and hard wired just as a regular battery would be: ground and pos battery cable. Thus +12v is distributed normally everywhere I need to test things. I now leave the key in ACC position and just unplug the supply, rather than continually reaching in and out of the car.

I probably will move it somewhere out of the way once I get back to engine work. When I finally get a real battery, I'm going to retire it to bench test use.

BTW, I may return it and get one with more oomph. It will can run my window motors on their own, but just barely.

Regards,

Ron