700mA vs 350mA

[thetoddjohnson]

That is not a typo. Yes, I'm asking about milliamps. I understand that this post is probably the least extreme question ever posted in the “Extreme DC!” forum, but I figured this is the place where I’d get the most knowledgable answer.

I have a small fan on which the label says “Input 12V — 0.70A”. I can not find the power supply, but I do have a different power supply that is 12V but only 350mA.

My intuition tells me that if I use the “smaller” power supply the fan will simply run slower. That would be fine with me.

However, my understanding of why we put controllers in our carts is because DC electric motors will pull as much current that is available. Does that mean that this fan will cause the undersized power supply to overheat and potentially be a fire hazard? Or is there a little .350A controller built into the brick?

Ironically, when I looked up the fan online (model number FB120382H) the webpage indicates it has a 1A draw.
http://www.hengruisi.com/hen/en/Pro_show.asp?/149.html

So, can I safely plug in this fan using this brick and leave the house?

Thanks,


TJ

FYI - The fan is built into a plastic hanger onto which I will hang a wetsuit. The whole reason for the fan is to simply keep air circulating through the legs and sleeves of the wetsuit until it is dry.

[Sergio]

Typically switch mode power supplies are designed to totally shutdown when the load exceeds their rated output.

Unfortunately there is not much "typical" about those cheap made in china walwarts power supplies.

The safest bet is to look at the fan to see if the positive is on the inside or outside of the connector and use a vernier caliper to measure both the inside and outside diameter of the DC plug.

You can easily find a 12v @1 amp adapter on Amazon that has the same DC plug measurements.

[thetoddjohnson]

Thanks Sergio.

TJ