Broke my Toriodal (zero dac)

[cdahl]

Hi all,

I have been mod'ing my DAC. Good for me!

I was repositioning the Toroidal and the black input wire came off.

I have been digging trying to find where to attach it back and I am causing more problems than I am fixing.

Ready to give up.

Problem is, this toroidal has NO MARKINGS on it at all. I contacted the manufacturer and got no response.

Does anyone know the specs for the toriodal that comes in the "zero dac" 09?

ref: 09 New Version Zero 24 192kHz DAC Head Amp USB OPA627 | eBay

I have been searching on the net for 3 weeks now.

Or have any suggestions for how to fix. It is a switchable 220/110 with 2 RED input wires and 1 Black. The Black originates at the switch. The output to the PCB is 2 yellow, 2 blue and 1 black.

I have zero power at this time and so have nothing to put the meter against.

Thanks

Wish my first post wasn't about something I broke

 

[AndrewT]

Disconnect from Mains.
Note existing good connections, so that you can return to original wiring.

If possible disconnect all leads from attached components.

Measure using ohm-meter, or conductivity meter, which wires connect to each other.
Label them.

Measure using ohm-meter, the resistance of each part winding and whole winding.

Mark up a sketch to show windings and resistances.
Post here.

 

[cdahl]

I'll see what I get after work.

Thanks

 

[cdahl]

Cheers,

Got a bit of the info you asked about.

Each red shows 110vac coming in

Black is broken with no end in site

I get connectivity between the repaired winding wire and the yellow secondaries.

That is all I got.

Is there a way I can measure between the red incoming and the yellow/blue secondaries?

Thanks so much for any help you can give.

Chuck

 

[AndrewT]

Check for conductivity between blue and blue.
Read the resistance.
Repeat for Yellow to Yellow
repeat for yellow to blue
repeat for yellow to black
repeat for blue to black
repeat for red to red
repeat for red to yellow
repeat for red to black
repeat for red to yellow
repeat for repaired winding to each of ALL the other winding taps.

Can you attach a probe to the broken black end?

 

[cdahl]

Hey Andrew,

Thanks for the instructions.

The broken black wire has no end that I can connect too. It is buried too deep in the windings.

I am on the road for a few days. I'll put the meter to the other connections on Monday and post the findings.

Charlie

 

[cdahl]

The results are in...

Hey Andrew,

Back from my trip.

Put the meter against the connections.

The following have connectivity:

Red >> Red 44.3 resistance measured at 200

Yellow >> Yellow 1.5

Blue >> Blue 2.3

Blue >> Black 1.3

Blue (second one) >> Black 1.3



The following did not have connectivity:

Either Yellow >> Either Blue

Either Yellow >> Black


Does that mean that this is a center tap for the Blue?

Is there a formula that tells the primary vs secondaries to figure the voltage out?

Thanks for any help.

I have gotten nothing for specs off the net or from Tianyun.

Charlie

 

[AndrewT]

Yellow is a separate winding.
Red is a separate winding.
Blue Black Blue is a centre tapped winding. Black is the centre tap.

Pity you can't access the broken Black.
It may have been a connection to an electrostatic screen.
Mains tappings are generally double insulated and as a result much more robust. You don't want broken mains wiring flailing around inside a conductive product.

Now that you have identified the different windings you can test the transformer before you connect it back up.

The easiest is the turns ratio (= voltage ratio on no load).

Apply a measured input voltage and measure the unloaded output voltage. Black to either Blue should be the same and Blue to Blue should be exactly double Black to Blue.
The input voltage ratio to Y-Y gives the Pri:Y turns ratio.
The input voltage ratio to Blu-Blu gives the Pri:Blu turns ratio.

If you have a Variac you can do further testing.

 

[cdahl]

Thanks Andrew.

I put this aside while I built a preamp.

Hopefully, I can get this working now.