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Hello,

I'd like to introduce myself in my first post as well as ask some questions. I am fairly new to electronics and have been learning on and off now for the past 4 years or so. I've amassed a fairly good sized inventory of parts and pieces, but need some help with a particular new acquisition of mine; a variable rate PSU.

The PSU I have is almost identical to this model.

My problem lies with the fact that while the output voltage for the PSU can be adjusted, the amperage cannot. Thus, it constantly supplies 2 amps and fries the majority of my electronics projects. I would like to know how best to reduce the amperage output of the unit. What would the ideal rating be for PID or arduino projects? Thus far I have gone through 3 resistors; up in smoke. Any help would be greatly appreciated.

Hola soy nueva en esto me podrían ayudar tengo que hacer un diagrama para medir amperios empleando amperímetro y para voltios utilizando voltímetro

https://www.circuitlab.com/circuit/37w3g2hjnp4v/21-voltmeter-ammeter/

Translation:

Hi, I'm new in this, you could help me, I have to make a diagram to measure amperes using an ammeter and for volts using a voltmeter

The supply produces a constant voltage. The current is whatever your circuit needs, up to the supply limit of 2A.

So for example if you set 6V and apply a resistor of 500 ohms it will take 6V divided by 500 ohms or 12 mA and the power will be 6V squared divided by 500 ohms or 72 mW.

See https://en.wikipedia.org/wiki/Ohm%27s_law and http://www.sengpielaudio.com/calculator-ohm.htm

ps - Your Arduino needs to be powered from seven to twelve volts at Vin so the setting of your supply should be 7.5V, 9V or 12V. Probably best to go for 7.5V.