Transformer with 6 outputs: a pair with 3 tabs each. Are these separate coils, or just redundant outputs?

[Jeff7]

I don't know if I can really just test this thing, as it is from a piece of damaged equipment.

It takes 115V input, and then on the other side are two rows of outputs, 0, 14, and 28 - one row on the top, and one on the bottom.

Are these separate outputs, as in, are there two separate sets of coils, allowing for two 28V outputs, and two 14V outputs?

It is marked:
DC-56-4
TRAN/SCAN
Concord NH

Primary side pic
Secondary side pic

Unfortunately, searching for "transformers tran scan" results in useless matches for Transformers - the transforming comic book robot variety, and their ability to Trans-Scan something. And of course there's no way to tell Google, "No, I want transformers, not Transformers!" :roll:
This language needs more unique terms, and fewer homonyms.


The circuit it's feeding is reading just about 2x the voltage at most of the test points, which of course seems odd. I'm just trying to figure out now if it's becuase the inputs are 2x what they should be, or if it might be a problem with the MOSFET circuit that's in between the PCB and the transformer.
I have tested the MOSFETs according to this low-tech test, and they respond as they should. Though I don't know if that's a truly comprehensive test.


In the meantime, I'l also check out the PCB - I rebuilt a badly damaged servo amp from scratch; it's possible that I missed a trace somewhere, or got a resistor value wrong.

The +5V test point reads 4.86V, but the -40V point shows -78V.
Very weird.

 

[Rubycon]

That's a multi tapped transformer. You can measure the resistance between the taps to confirm. A 0 tap is usually the center or it could be can (reference ground?)

Post a pic if you can.

 

[bruceb]

You might have better luck if you can provide the Make & Model # of whatever this thing came out of. But what you have is either 3 seperate secondaries or one big secondary with multiple output taps. If that is the case, use a Digital Multimeter set on the Ohms function. Connect one test lead to a lug and then go to the other three one by one. See if you get resistance between them. If not, repeat by changing common test lead. If you find one lug that does connect to all the other 3, then you have a multi tap secondary.

 

[nineball9]

Perhaps it was made by this mfg. (I searched on inductor concord

However if I had the part in hand and was trying to figure it out , like previous posters, I would have simply done resistance measurments instead of relying on google. Unless it's an IHT - unlikely from your description - there won't be any integrated passive components in the transformer which would confuse resistance measurements.

 

[Jeff7]

Originally posted by: Rubycon
That's a multi tapped transformer. You can measure the resistance between the taps to confirm. A 0 tap is usually the center or it could be can (reference ground?)

Post a pic if you can.

I'm just wary of testing any of this stuff, since I can't be sure if any of it works.

I've also got a choke there (looks like a small transformer), which may have taken a hit from a short.


I'll try to get pics tomorrow, and a model # of the device.
It's a servo amplifier I've been fussing over for awhile. I have no thorough information on it, no specs, nothing technical, just the user manual, which assumes that it's working 100% properly, which it most certainly is not.



Edit: I'l be able to upload pics this evening; I've got no hookups here at work for the camera, and the permissions on the PC I have don't permit adding new hardware.

And I may have to repair the rebuilt servo amp board - I ordered TO-92 transistors to replace the TO-18s that were there before (budget concerns and all).
Datasheet for one of them.

If the views on the page are how I think they are, the EBC configuration is backwards from what I was expecting - and I think I may have toasted 9 transistors on the board, and hopefully nothing else.
One that I pulled is showing shorts across all lead pairings, regardless of polarity.

 

[Jeff7]

Pics uploaded, also in OP.


Primary side pic
Secondary side pic