Saturday, January 28, 2012

Power Supply variable with lm338

lm338 v.1 dual power supply

This lm338-v.1 power supply will be able to give something like two times 12- 36 volt and 2x5 amps (10 amps in the v.2 of this PSU witch includes transistors to get more current from the circuit). 

The trafos used are already able to deliver 2x 10 amps continua and 12 amps peak or so..

I use 2 x lm338 in V.1 but also lm317 can be used. I will use extra transistors to get the current up i V.2. Schematic will be equipped with current limit adjustable in steps, a current limiter with LED indicator, and i will try to find some way to make a reset able relay, than automatically disable output when short circuit or to high current drawn, Also i have some temperature sensible switches so power supply will shutdown at to high temperature on the cooling plates.

Basic DRAFT schematic from a test i made earlier.

Basic draft schematic of the dual lm338 PSU, without current limiter, short circuit protection and more

The cabinet with trafo'es, placed on my kewet electric vehicle bonnet.
The power supply is intend to be used to supply the EV when testing and adjusting lights and more optimization. No need to misuse the batteries ;)

Colling plates for the two lm338, and some pnp transistors like mj2955, or some sanken maybee

I use scraped knobs and gold plated banana plugs from a scraped nad 319 amplifier

At the side plate i have clued nappa leather

I do think this is a easy way to make functional test equipment. I will place 4 x led panel meters for voltage and amperes.

I use avery metal foil for laser printers to print the text for the front plate

 Frontplate with schorcut circuit rest, potmeters and output connectors

Shorcut protection circuit with relay in front between trafoes.


Current limit: high amp psu with current limiter 


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