how to power multiple devices on one 12v dc power supply?

A)   So i'm upgrading my soldering fume extractor as the OLD model looks ancient.. the old model ran x5 12v dc fans with the following current rating ( 0.12A,  0.25A,   0.41A,  0.40A,   0.40A ) and 3 standard 5 mm led's.  POWERED BY 12v = 500mA DC power supply



B)  the NEW model will have x4 dc fans @ 0.41a          x1 12v 360 degree W5W led  0.41A           x6 5mm leds     x1 arduino Nano.

My questions are:

1) How did i power the OLD model (A) with that power supply. from my understanding if doesn't supply enough current. 

2) Can i power all the components in the NEW model(A) with a 12v 1A supply  and if not how can i power all these components from 1 plug?

thanks for your help

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1) No clue.
2) No
You need a power supply with at least 2.5A to be on the save side.
I don't know about your plug, but you simply connect all devices in parallel to the power supply.

rickharris1 year ago

Your understanding is correct, However what is written on the outside of a PSU may be very different from what current it can provide, it may be a standard unit de-rated on the label for a particular purpose or it may just have been quite hot!.

As Du35 says hard to know without being there.

Fact is that you need at least 2 = 21/2 amp.

icey.hood (author)  rickharris1 year ago

does it make any difference if i wired my darlington TIP122 directly to +ve and the fans +ve connected to ground of the transistor?

As there is no mention of a Darlington transistor in the question i have no idea what this is or where it is.

Circuit diagram of at least a good full description required.

icey.hood (author)  rickharris1 year ago

My apologies, in the future i will elaborate and give a full description. I am sending a signal from an arduino to turn the darlington on, turns out it either makes a difference or my soldering was terrible. In any case the issue i was facing has now been resolved. Thank you very much for your assistance, much appreciated.

icey.hood (author) 1 year ago

does it make any difference if i wired my darlington TIP122 directly to +ve and the fans +ve connected to ground of the transistor?

iceng1 year ago

I take it you did not measure the currents but were reading the fan ratings...

1) Possibly the old unit was pulling a vacuum which unloads the fans and they use less power.

2) No !

Downunder is correct about the power supply.