Login

Recent searches

No recent searches

Search options

Only available when logged in.
fosstodon.org is one of the many independent Mastodon servers you can use to participate in the fediverse.
Fosstodon is an invite only Mastodon instance that is open to those who are interested in technology; particularly free & open source software. If you wish to join, contact us for an invite.

Administered by:

Server stats:

10K
active users

fosstodon.org: AboutStatusProfiles directoryPrivacy policy

Mastodon: AboutGet the appKeyboard shortcutsView source codev4.3.6

totoroot

Can somebody, familiar with these kind of , please help me to identify this transformer, which was part of the power supply circuitry inside a .
A colleague of mine brought me his broken after, according to him, it had sparked out of its ventilation slits near the power plug, when he plugged it in.
I looked at the circuitry and it became rather obvious that the transformer gave out, as the PCB was charred around it.

1/2

The power supply circuitry of a disassembled projector. The big electrolytic capacitor was already desoldered and there is an obviously charred spot next to a transformer
The power supply circuitry of a disassembled projector. The big electrolytic capacitor was already desoldered and there is an obviously charred spot next to a transformer
The power supply circuitry of a disassembled projector. The big electrolytic capacitor as well as the transformer were already desoldered. The rest of the disassembled beamer can be seen in the back, along with some tools for soldering spread around it all
The power supply circuitry of a disassembled projector. The big electrolytic capacitor was already desoldered and a hand is holding the desoldered transformer
#ElectronicsRepair#DIYRepair#RightToRepair
Aug 15, 2023, 08:43 PM·Public
1boost·0favorites
Public *
totoroot

Some more pictures. The top of the transformer reads "2940489" and "UM1413CG". Any ideas how I would go about finding out the electrical characteristics of this transformer so I can replace it with a fitting one? 🤔

Boosts for both posts very welcome! 🔄

2/2

The bottom side of the power supply circuitry PCB. No obvious damages
The power supply circuitry after having desoldered the big electrolytic capacitor and the charred transformer
A hand holding the desoldered transformer
A closer view of the power supply circuitry after having desoldered the big cap and the transformer
Public
mike805

@totoroot Are we sure that didn't come out of the capacitor? The transformer in a switching power supply is usually custom for that power supply. Capacitors, however, are easy to replace, and blow up more often than switching power transformers do.

Public
totoroot

@mike805 Not entirely sure, no. But I'm quite confident in saying it's most likely not the cap in this case, as it looked brand-spanking new after I desoldered it. There were no charred spots on its bottom and it did not look ballooned at all.
After desoldering the transformer, I was quite certain that it was the component that gave out.
I suspect that two windings shorted and caused the sparks, but I'm not sure how to best test the broken transformer 🤔

Public
mike805

@totoroot well if it has two windings there should be no continuity between them. If there is, your best bet is probably getting a similar projector with something else wrong with it and swapping parts.

Quiet public
Jue

@totoroot Looks like a fly-back transformer. Unfortunately, most of them are specifically designed for the switching IC or even the demands of the circuit it’s powering.
You could try to find the respective switching IC on the board and look it up. Maybe its datasheet contains some hints which transformer that might be.

ExploreLive feeds
About