Power supply current problem

[Pexy]

Hello, guys. Yesterday I bougt a power supply (15V, 2A) made by a colage student and checked by his profesor for around 15 US$. When i went to test it out with a multimeter the voltage was around 15V but when i went to test current it didn't show anything. I conected the multimeter in series with a lava lamp to test the current (the first time). When i conected the multimeter in series with the lamp and a car battery charger it did show the current and the lamp did light up(the first time it did't).
If you have any idea why it doesnt output current please suggest something.

 

[davenn]

what voltage and current does the lava lamp require ?

 

[Pexy]

what voltage and current does the lava lamp require ?

12V 2A

 

[AnalogKid]

Photos? Schematic?

ak

 

[(*steve*)]

Maybe it can't supply 2A, or perhaps it trips out when the bulb in the lava lamp demands more than 2A (as it will when cold or powered from > 12V)

 

[Colin Mitchell]

Connect a 10R 10w resistor. Does it get hot?

 

[Sunricher]

Maybe you need a power supply with higher current than 2A if the lava lamp requires 2A.

 

[Pexy]

I also tried connecting it to a small dc motor, a wire from a styro slicer and a bunch of LED's. Still nothing
Schematicks and pictures are on the way.

 

[Pexy]

The yellow bulb is for Outout break(roughly translated), and a small red switch is for Output reset. It has a small buzzer that goes of when smoething is wrong (or something else)

 

[(*steve*)]

Colin's suggestion is a good one if you have a 10Ω 10W resistor.

 

[Pexy]

Colin's suggestion is a good one if you have a 10Ω 10W resistor.

It doesn't get hot or warm.

 

[(*steve*)]

do any lights come on?

what is the right hand knob set to?

 

[Pexy]

do any lights come on?

what is the right hand knob set to?

The constatn voltage light comes up. The right knob was set to max

 

[(*steve*)]

Ok, measure the voltage across the power supply output before you place the resistor across it, then with the resistor across it, then after you've removed the resistor.

 

[AnalogKid]

That is a lot of parts for only 30 W, and an...inexperienced pc board layout, but neither of those things is automatically bad.

1. When the load resistor is connected, does the red constant-current LED come on, or blink briefly, or anything like that?

2. Does the amber overcurrent LED come on?

3. Does the supply behave the same when adjusted to high and low output voltages?

4. Also, what is the part number of the power device bolted to the rear panel?

ak

 

[Pexy]

I took it to my school and profesor said it is probably the regulating IC or one of the relays