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SMPS troubleshooting aid

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dr_p:
I admit from the start I'm new to switch-mode power supply repairing, but keen to go at it.
This thread is aimed at inspiring other people to build things, maybe even duplicate this type of equipment.

I have, so far, stumbled across some inconveniences:
  - the series light bulb trick is annoying without an actual box to hold the bulb, plug and maybe a switch.
  - having to constantly plug-unplug the power supply, having to constantly trace the wire from the SMPS to the plug, making sure IT is unplugged, not something else. My desk is a mess, that's why.

So I decided to build a box with a plug, switchable on-off, with a series light bulb that can be bypassed. Actually I used a normal E27 and a small E14 bulb fixture, so I maximize my chances of having a compatible bulb. Added fuses and an analog voltmeter on the output, since I was dying to use it somewhere :D
Since I was at it I bundled a DIY isolation transformer, made from two identical toroidal 100VA 48VAC transformers. I think it's enough for most SMPS.

Now I find it so easy to work on any mains project: I have a master on-off switch, crude current limiting from the bulbs and a low value, fast blow fuse to keep things safe.


Below you have the schematic (for what it's worth) and a picture of the assembled unit.

PA4TIM:
Nice build. Some switchers refuse to start with a series lightbulb.
I have done about the same. But just one lightbulb. I am still thinking about an alternative for a lightbulb or sense current and at a adjustable level a lightbulb switches in as protection.
I use a 1:1 isolation transformer and a variac. Also 32VDC, 6,3VAC, 250VDC and 0-1200VDC

http://www.pa4tim.nl/?p=1572 this is mine, but not as nice looking as yours

SeanB:
Instead of the 3A fuse place a DIN breaker of 5a or a 3A unit if you can get it in it's place. Resettable and both fast acting and will handle surges. I have a whole box of them in a drawer, still trying to use them up.

Alana:
I sometimes "do" PC PSUs and i made smaller version - just lightblub socket and bypass switch in small case.
You may want to get as big lightblub as you can find - 60W is too low for most ATX PSUs, especially those with active PFC.
Fuses - I'd get rid of them or replace with resettable beakers above 6A. Entire thing about this box is that you have light blub as overload protection and fuses - especially those values may be problematic and burn out when not needed - for example because of initial current surge of unknown SMPS.

Analogtech:
Thats a very nice build and the schematic was bloody well made but you do need to make sure that the lightbulb can stand up to the inrush which can be pretty high for some SMPSs  and you might want to get rid of the fuses and use breakers instead it can get annoying replacing fuses

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