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Transformer identification resources(Line6 spider III)anyone got info on these?

Started by Zappacat, August 03, 2009, 12:54:25 AM

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f_b_ilies

OK, I'll send you the info. It is possible that the transformer survived indeed. This is what happened actually:

- I was mislead by the label on the back of the power unit, which kinda suggested that it's a dual transformer (see pic above). Should've looked it up first, but it was an honest mistake at the same time. If you check the Line6 forum, there are 2-3 cases every week with people repeating the same mistake over and over. So I replaced the fuse from T4A to T2A, plugged it into 220V and boom, the fuse blew. Tried with another T2A fuse, same thing.

- then the fatal mistake, I put back the T4A fuse and plugged it into 220V. The fuse didn't blow anymore, but I smell and saw smoke. I turned it off right away, it was on only for less than a second

- then I got a 220V-110V transformer, a very small one 25-30W. I tried with that one too, I got the amp display on and a hum in the speaker, but none of the buttons worked. So either there wasn't enough juice given by the 220-110 transformer or the amp transformer survived, but the electronics in the amp burned :(

Let me ask you, in theory, what happens with the output voltage of a transformer, if we double the input? Say we have a transformer 110V->15V and we plug it into 220V, will we get double on the output (30V)? If so, that's bad news for my amp, unless there is some kind of 3rd level protection there (in case neither the fuse nor the transformer blow).

I'm still hoping that the amp is fine and only the transformer died, for 2 reasons:

- I wanna trust what the Line6 guy said
- I think I remember my uncle measuring resistance on the output wires (blue, blue, brown, brown, black) and there was no continuity, so he concluded the secondary might have fried

I'll come back with the measurements you asked for.

mensur

Does your amp has 2xTDA7294 chips in poweramp section, or is it discrete one?Take the pics of the poweramp section, we can determine +/- volts by the poweramp, and by the number of winding loops as your uncle said.

phatt

Quote from: f_b_ilies on June 08, 2010, 04:24:50 AM


Let me ask you, in theory, what happens with the output voltage of a transformer, if we double the input? Say we have a transformer 110V->15V and we plug it into 220V, will we get double on the output (30V)? If so, that's bad news for my amp, unless there is some kind of 3rd level protection there (in case neither the fuse nor the transformer blow).



Oh dear  :'( Yes absolutley,,, when you double the primary it doubles the secondary VAC, So yep you likely fried the whole thing.
An that's usually everything $expensive$ :'(
Phil.

f_b_ilies

I'm still hoping for some kind of 3rd level protection, there are some condensers in the front line

J M Fahey

Problem is, semiconductors fry in 1 (one) milli-second, I'm not joking.
The first time, *maybe* the 2 A fuse blew with the original current trying to charge the filter capacitors, before they charged to an important voltage, because it takes a very short but definite time, but with your second, 4 A fuse, which did not blow ........  you nuked everything.
Anyway, I am trying to believe that your 160 € transformer survived, simply because of its cost and unavailability.
If you burnt those TDA7294, well , that's normal , it's built-in (at least Marshall thinks so) , they can be replaced.
Now, if you burnt that do-everything DSP, forget about your Line-6, now you have a nice chassis, cabinet, power supply and speakers to build, say, a Rodd Elliott preamp driving a couple TDA7294 and a couple Eminence speakers, which, mind you, will sound very good (although without effects).
If your transformer died (which might not have happened) , you can buy any regular transformer needed to power a couple TDA7294 or LM3886.

f_b_ilies

The data I promised earlier. I draw a few sketches, took some measurements:

- first of all, I figured out what the 2 connectors (110/220V) on the motherboard are for. They simply drive the AC input coming on the B&W wires to different pins/wires (black/yellow/red) to be fed into the transformer. For 110, ground falls on the middle pin (red wire), while for 220 it falls on a side pin. It seems the 2 types of transformers have the input wires arranged differently. I figured this out by plugging the amp to 110V (via 220-110 transformer) and unplugging all transformer wires, then measuring the pins. See pic. Not sure this is correct, I thought ground is usually yellow, but this is what came out of the measurement.

- then I measured resistances on the transformer, see diagram

- I also measured the output voltage on the transformer and was surprised to get AC instead of DC. Is that correct? Values quite high also, 36.8V. So it seems the transformer survived, allthough not sure it's giving the right output. Either way, it's bad news for the amp part

- took some more pics of the boards, it seems I have an LM1086, an LM317T and another one MC7805CT. There is a DSP chip also.

Does it all fall into place? Is that 36.8V accurate or my tester is bad? I still wanna figure it out and buy a replacement transformer, so I can take it back to Line6 for further troubleshooting. I'm still hoping it's only a transistor or a condenser.


phatt

Hi f_b_ilies,
Ouch again!
You really need to consider learning the *Basics First* before jumping inside stuff you don't fully understand. (Now you are paying the price)  ::)

Transformers work on AC Volts only, that's Alternating Current.
i.e. 240VAC @ 50hZ.   Or 50 times a second it alternates.
DC (Direct Current) does not alternate.

It's all AC until it passes the Diodes which transform the AC voltage to DC.
(Your *Diodes* are in that black square thing, should have 4 legs)

Your reading of 36 V *?* means little to us as you have not qualified if it's AC or DC your meter is reading.

Google *Rectification* I'm sure you will find something that may help you to understand the basic principle of converting AC to DC.

Your *36 volts* is likely to be the *Rectified DC* that powers the circuit.
A clue to this can be found by reading the working voltage on the side of those 2 large Electro Caps on the board. If they read 50Volts then you secondary DC will be *Below* that voltage.

Your secondary AC is likely to be around 25-0-25 VAC which will deliver the 37-0-37 VDC.
(This is a common voltage for amps in this class.)

In these circuits the VDC is *Split around Zero Volts*

So you have a *Positive Voltage and a Negitive* and Zero or common.
hence 3 wires 8|


Go here http://evatco.com.au/hamptchoke.htm

Click on
**Transformer Selection Guide**

If you are intending to learn *How stuff works* You will need Know this one day,,,
so Save it and print it out.
Phil.

J M Fahey

Quote- first of all, I figured out what the 2 connectors (110/220V) on the motherboard are for. They simply drive the AC input coming on the B&W wires to different pins/wires (black/yellow/red) to be fed into the transformer. For 110, ground falls on the middle pin (red wire), while for 220 it falls on a side pin. It seems the 2 types of transformers have the input wires arranged differently. I figured this out by plugging the amp to 110V (via 220-110 transformer) and unplugging all transformer wires, then measuring the pins. See pic. Not sure this is correct, I thought ground is usually yellow, but this is what came out of the measurement
NO NO NO NO NO NO NO .....................YOU ARE GOING TO DIE............................
1) YOU ASSUME THAT SOME PRIMARY CONNECTION GOES TO GROUND, OR "IS" GROUND, IT IS NOT.
NEVER ANY PART OF THE PRIMARY IS OR TOUCHES GROUND OR ANY PART OF YOUR CHASSIS ..... NEVER.
2) Your transformer does NOT have a 110V/220V primary.
It EITHER has a 100V/120V tapped primary (your case) OR it has a 220V/240V tapped primary (yours does not)
3) You need a 220V/110V transformer to use your amplifier.
4) Your transformer is fine, you just saved €160 or whatever.
5) Your amplifier is, VERY probably dead (sorry)  :'( :'(
6) In the VERY UNLIKELY case that your amp survived, just for peace of mind, replace all fuses as stated in the manual or the different labels (use those related to 120V), plug into a 220/110V transformer, size at least 150VA, preferably 250to 300VA and power it on.
If it works, pray a lot and donate to some charity, you'll feel better after doing that.
If it does not, you have a beautiful cabinet, speaker, chassis and PSU to build an LM7294 or 3886 kit and some preamp.
Good luck.
PS: your drawings and measurements were EXCELLENT, very useful, I felt as if I had the amp on my own bench, thanks.
Pity the diagnostic was not the best.

phatt

Thanks Mr, Fahey
Whoops I missed that one. :-[
Good to know chaps like you are floating around to pick up the Fatal mistakes. :tu:
Personally I think this chap should quit while he is still breathing and hand it over to someone *Qualified*.
Phil.

f_b_ilies

Thanks Phatt!

I actually said that the 36.8V is AC, that's why I was surprised. If you check the diagram, I also stated there that all voltages are in AC. It makes sense now with blue/black/blue wires, but I still don't understand the two brown wires where I get the 10.2 VAC. Is that powering another area of the boards or something? So I still don't know what to ask for if I go to a shop. A 220VAC to 36.8VAC/10.2 VAC transformer, 75W? Is that it?


f_b_ilies

Quote from: J M Fahey on June 10, 2010, 08:07:59 PM

Quote

NO NO NO NO NO NO NO .....................YOU ARE GOING TO DIE............................

 ;D I think I was safe, I didn't touch anything directly, only used the tester.
Quote
1) YOU ASSUME THAT SOME PRIMARY CONNECTION GOES TO GROUND, OR "IS" GROUND, IT IS NOT.
NEVER ANY PART OF THE PRIMARY IS OR TOUCHES GROUND OR ANY PART OF YOUR CHASSIS ..... NEVER.

If it's not ground, that I don't know what it is. This is what I did:

- unplugged all transformer wires from board
- only plugged the B&W wires to the board
- plugged the unit into a 220V-110V transformer (~25W), then into the wall socket (220V). So at this stage I had the whole transformer off
- then I measured all pin combinations on the 2 connectors on the board (where the B/R/Y wires should go). Since I didn't get any reading on the pin that I marked with G in combination with any of the other 2 pins, I figured that must be the ground. Then on the remaining 2 pins I measured 120VAC

Quote
2) Your transformer does NOT have a 110V/220V primary.
It EITHER has a 100V/120V tapped primary (your case) OR it has a 220V/240V tapped primary (yours does not)

Yeah, got that.

Quote
3) You need a 220V/110V transformer to use your amplifier.
4) Your transformer is fine, you just saved €160 or whatever.

I'm debating whether to buy a 220\110 transformer or a cheap replacement for the original transformer (220V version). To which I'm still not sure about all the specs (for example the 2 brown wires). The 220/110 transformer seems an easier option.

Quote
5) Your amplifier is, VERY probably dead (sorry)  :'( :'(

Yeah, now at least I can go to phase 2 and still hope for an easy fix (a condenser or something). I think I'll just buy a 220/110V transformer and take it back to Line6 for further troubleshooting, so they can at least power it up and look further. Allthough their level of expertize is now questionnable, since their diagnose was that the transformer is dead. I'm granting them that they had to guess, since they didn't have a 220/110 transformer to power up the unit for measurements.

Quote
6) In the VERY UNLIKELY case that your amp survived, just for peace of mind, replace all fuses as stated in the manual or the different labels (use those related to 120V), plug into a 220/110V transformer, size at least 150VA, preferably 250to 300VA and power it on.

One last question: since I don't have such a big 220/110 transformer yet, I had to use a 25W one. Now if I get the lights on and a hum in the speaker, is that a bad sign or a good sign? Is it suppose to work with a 25W transformer anyways or it just doesn't give enough juice to power the amp properly and maybe that's why I get the hum? Just for me to sleep better during the weekend, until Monday when I can buy a proper 220/110 transformer.  :)

phatt

Quote from: f_b_ilies on June 11, 2010, 08:06:15 AM
Thanks Phatt!

I actually said that the 36.8V is AC, that's why I was surprised. If you check the diagram, I also stated there that all voltages are in AC. It makes sense now with blue/black/blue wires, but I still don't understand the two brown wires where I get the 10.2 VAC. Is that powering another area of the boards or something? So I still don't know what to ask for if I go to a shop. A 220VAC to 36.8VAC/10.2 VAC transformer, 75W? Is that it?

HI FB,
Look I've missed a couple of things,, sorry for that.

With all due respect if people here do not even understand the function of the transformer then those people put other folks in a very awkward situation.
Safety is a real issue when playing around inside gear.

I quote you from a previous post;
"I also measured the output voltage on the transformer and was surprised to get AC instead of DC."

It's those kind of comments that tell me you don't have enough knowledge to fix this thing. :grr

JMF has given the best advice,,,if you are smart quit now and hand it to someone with the ability to trouble shoot what's wrong,,,or trash it as you've likely fried it all anyway.

No disrespect mate but I'd rather you hate me than to find out you are DEAD. 8|

If your measurements are indeed correct (unlikely but possible) then there is a very high risk of FATAL electric shock.  NO Not from just the mains ,,,BUT FROM the 2 DC rails which may have 100VDC floating between them. 36x 2= 72. 72x 1.4= 100VDC that's 50-0-50VDC Rails.
Touching both Pos and Neg rails will leave you with no time to say;
Hey man, maybe, Zit I should have, Zit taken Phil's advice, Zit. :-* :-*

Anything above around 70/80 Volts (DC or AC) is deadly dangerous and should be treated with the same respect as the mains. :trouble

I have an Amp here right now with 140 VDC between the Rails,,, spooky ,,
I hate working on this big stuff.

So go check those 2 Big Capacitors (next to the square black blob, the Rectifier) and *Read The Working Voltage* **(What does it read?)**
The VDC inside the Amp circuit will/should always be *Less* than what is written on those.
That will at least give you some idea of what your DMM should be reading.

*****I sense, Something is very wrong with those measurements you give******
Phil.

f_b_ilies

No worries Phil, I don't hate you  :) You are only trying to help. I don't have the basics indeed, but I thought measuring a few things can cause no harm, as long as I keep my fingers away. And I only did that because I did take it to "professionals" first, but they gave me BS. So I had to go on my own, at least for the first part. I only wanted to know if the transformer is OK, so I can go for the 220/110 transformer or otherwise go with the original 160 EUR transformer (or a cheap replacement, if I could figure out the specs). I have my answer, I'll go for the 220/110 transformer. Which is actually a prerequisite for the next level troubleshooting. So that's it, I'm off of it, I will certainly do not replace any parts myself. I'll take it to someone, but I wanted to get some basic understanding so they don't BS me again.

Thanks for your help!  0:)

J M Fahey

Hi f b ilies, ¿you still with us?
I got a little worried now that you started to sign using the "angel" emoticon -> 0:)<- .
Well supposing it only means your good heart (in both ways: good feelings and resistance to mains current through it) we can go on a little further.
To begin with, you can *start* testing with your 25W 220/110V transformer.
If you get DC power from that bridge and capacitors , say, about +35V and -35V or thereabouts, I can trust that your transformer and main power supply is still good.
The low voltage winding (around 10V AC) probably powers a +15/-15V supply for the op amps and +5V to the DSP area.
Even if the digital part is dead, meaning you don't have a "spider something" there any more, at least you can mount a couple conventional boards there and play your guitar.
Anyway, buy that 250W or bigger (as much as you can) 220/110 transformer, because no doubt , now or later, you'll have more stuff to use it.
As of the Line 6, not even the factory repairs them, they just dump the boards and give you a new one (if under warranty) or tell you to dump the full amp itself, if not.
Good luck.