URGENT: SMPS underpowered.

[sumedik]

Hello all,

Well this is my 1st post here, I hope somebody can help me out.

My SMPS(300 watt) is connected to the wall power plug socket via a tripper switch. 2 days back I saw that the tripper is tripping immediately when I switch on the SMPS.

I tried by disconnecting the tripper switch from the circuit. But then the CPU refuses to power up.

I took out the SMPS and connected to my friends PC and it works perfectly. However the plug point at his place supports a 450watt SMPS(his regular SMPS)

Does that mean that after prolonged usage my SMPS has started consuming much more power than 300watt(due to reduction in efficiency) and therefore it is triggering the tripper switch?

Or could it be something else? The earthing in that plug point is 100% OK.

Also how to check if that plug point has the capacity to support a 600 watt SMPS in future, when I upgrade my PC?

Please share your knowledge.

Regards.

 

[jonnyGURU]

Tripper switch?

You mean the plug has a GFCI on it that keeps tripping?

A 300W PSU is going to draw more than 300W under full load because the 300W rating is DC, not AC. But your wall outlet should be able to provide at least around 1400W without tripping unless there are other things on that same circuit that are using up (significant) power.

 

[sumedik]

Thanks for your reply.

Yes it is GFCI. It looks like this:

http://www.o-digital.com/uploads/21..._Switch_Off_Miniature_Circuit_Breaker_927.jpg

Yes I am shocked why the CPU refuses to power up even if I connect the SMPS to another plug point without GFCI.

How to check how much output the plug point is capable of producing, even though it is supposed to 1400W theoretically.

 

[jonnyGURU]

Well... the only way you can check to see what load the outlet is capable of is to load up the outlet. Can you run a vacuum cleaner off this outlet?

 

[Modelworks]

That is just a standard circuit breaker, easy way to tell the difference is gfci or arc fault will have a test button on the breaker or outlet.. It should not trip with a 300watt load unless there is something else on the same breaker. Has anything new that plugs in been added to the room ?

 

[sumedik]

Well the problem was finally tackled by getting a new 450 watt SMPS. I just could not find someone to reair the existing one at a reasonable price, and it was dificult without the home PC, so....

Thanks for your replies people, would get a new PC soon, and i am sure i would have a lot to ask....

 

[seglob]

There are some small inline connectors for most of the SMPS output voltages, and a couple push on connectors for the B+ wires. I forget, are they violet and orange? NO matter. Pull the B+ wires off and unplug the low voltage output connectors. Now the SMPS can power up with no load. Check for voltage at those B+ push-ons as convenient. Does the SMPS wake up?

As with any other tube amp, the most likely failure is a power tube. And that can damage the SMPS. If the SMPS works alone, then find the problem in the amp - pull the power tubes and reconnect the SMPS - power up?

If the SMPS doesn't fire up unloaded, then pull it. BE EXTREMELY CAREFUL, THIS THING RECTIFIES THE MAINS DIRECTLY. The primary side of the SMPS is NOT refernced to ground or chassis. The secondary side supplies are referenced to chassis though.