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Electronics => Repair => Topic started by: BrianBro on June 11, 2016, 12:56:14 pm

Title: Problem power supply
Post by: BrianBro on June 11, 2016, 12:56:14 pm

Hi, I have a Pyramid 12 volt power supply that when I put a load on it the power drops to around 5 volts. Does anyone know what component or components might be bad?

Title: Re: Problem power supply
Post by: rolycat on June 11, 2016, 01:20:10 pm

Insufficient data.

• What model of power supply?
• What sort of load?
• Have you tried other loads?
• How much current is drawn when the load is applied?
• Have you opened the supply to see if there are any obvious faults?

Incidentally, power is not measured in volts.

Title: Re: Problem power supply
Post by: BrianBro on June 11, 2016, 01:48:01 pm

The model is Pyramid PS-26KX and it doesn't take much current for it to drop. About an amp. Everything inside looks good. Nothing burnt

Title: Re: Problem power supply
Post by: rolycat on June 11, 2016, 04:45:31 pm

A good start would be to check the electrolytic capacitors, as these are a frequent source of PSU problems. Look for bulging tops and/or leaking electrolyte. If you have a multimeter you could also check the output ripple using the AC volts setting.

Also check for unusually hot ICs, resistors etc.

Title: Re: Problem power supply
Post by: BrianBro on June 11, 2016, 10:15:38 pm

Ok thanks, I'll see if I can find anything