surplus power supply

[star882]

I have found a surplus power supply.
It is a toshiba PA2478U.
The output is 18v,1.7A.
The entire power supply is much lighter than a 24v,1.3a transformer.
Got any idea why it is so light?
Are these overload protected?

 

[luxO]

"Got any idea why it is so light?"

As we discussed in your other thread about the weight difference in power supplies. The reason it's so light is that it is a switched mode power supply, just like the typical PC power supply.

 

[star882]

It is a plug in cube(wall wart), not a supply in a box.

 

[luxO]

what difference does it make weather the supply is in a box ...or in a box with a plug on it?

 

[louie]

Another clue that it's a SMPS (switch mode power supply) is that it is self setting from 100 VAC to 240VAC. Linear power supplies never do that. http://209.167.114.38/support/Tsbs/300/tsb0325.htm

Overload protected? Who knows, it's for a laptop, it probably has some protection. 2 ways to find out! open it up and reverse engineer the circuit, or try shorting it out!

 

[star882]

I never heard of switchmode wall warts.

 

[lux0]

Originally posted by star882:
I never heard of switchmode wall warts.

<font size="2" face="Verdana, Arial">well, the rest of us have, and, they're very common.

 

[louie]

Yep, I have a Nokia phone charger wall wart. It's very small, so light you can't believe anything is inside, and is self setting from 100-240 VAC. I am assuming it is a SMPS.