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What is this device - Inside a SMPS

What is this device - Inside a SMPS

What is this device - Inside a SMPS

I contacted gould for a schematic as they are the manufacturer, but they never got back to me. Judging by the components this unit is probally from the 70's.

12 volt switch mode power supply. Some wires came loose and I hooked them back up based on my assumed color scheme of 110 in blue/brown to the smaller transformer wires blue/brown. The pins the ac was connected to had continuity to the pins on the other end of this device.

Anyways here are some pictures. It has 7 pins and this PCB soldered to the top of it. http://www.bright.net/~jarc

RE: What is this device - Inside a SMPS

A potted transformer, maybe?  I'm not quite sure what component you're talking about...

Dan - Owner

RE: What is this device - Inside a SMPS

It's the black rectangular piece in the first picture. I am not sure exactly how old this SMPS is, because I cannot find any papers on the Gould MG15-16c

It seems odd to be a transformer. There are two conventional looking transformers in the other parts of this SMPS. I've seen one of these or something very similar to it in a ham radio parts drawer.

I guess it would make sense to be a transformer as the power comes out of it to a diode bridge on the pcb that is mounted to the top.

I don't understand why there are so many pins out of it though and I cannot find reasonable power coming out of any of them. I beleived this to be the component at fault for the SMPS not working anymore. I am thinking these were a special bridge or something used in ham and power supplies back when this was built.

You think I should take it out and dissolve the potting to check it out? I've searched the net for all kinds of things and cannot find a similar looking device.

RE: What is this device - Inside a SMPS

Hey guys, that's what I was thinking. I posted some pics of the device after I removed the diode bridge pcb that was on top of it.

I can now see where my + and - is supposed to go out to my switching transistors.

The L and N is line and neutral I imagine, and then the smaller transformer inside this SMPS connects two of its primary inputs. to FN and FL, the only thing that is left is a chassis ground (green yellow) that has no continuity to the - on this input transformer.

My best guess is that the E means earth ground on this said device (input transformer)

The FN and FL go out to the "small transformer" in the SMPS - there is also a green/yellow tap on the same side of the transformer - I am thinking this is a ground center tap.

By the way, I found my culprit after removing the board from the main transformer - a bad wire wound 18ohm resistor - you can see the wires through a small clear spot of the coating and they are "open" I am hoping the resistor was just bad or a wire broke loose and caused a short.

Thanks for the replies guys.

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