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Power supplies are notoriously failure prone across all possible uses. 1. By definition, they're the device with the most current running through it, and typic
by nwallin 7y ago
Power supplies are notoriously failure prone across all possible uses.
1. By definition, they're the device with the most current running through it, and typically generating the most heat. Switched mode power supplies have efficiencies up to around 80%, linear mode power supplies closer to 50%. They need to be cooled, but typically aren't or have insufficient cooling.
2. They're typically chock-full of electrolytic capacitors.
3. Power supplies have been engaged in a race to the bottom for decades. You're almost always getting the cheapest part from the cheapest factory.
The power supply should always be the part you troubleshoot first, even if you see something else smoking. Chances are pretty good the reason the other thing is smoking is because the power supply is putting out too much voltage.
- marble-drink 7y agoThe power supply in this case was just a wall-wart plug and I always thought they were just transformers which are too simple to fail. But thinking about it now, there must also be a rectifier in there at least. Maybe there's much more than that...
- Moru 7y agoAt a previous job the most exchanged part was powersupplies for routers and fiberconverters. For some shipments we had more than 50% failure.
- NikkiA 7y agoTransformers often fail after a given 'long time', they are usually made out of many laminated plates glued together, and over time the glue will fail, plus they tend to vibrate at the mains frequency, which can shift things around over time and cause failure too.