Trying to match small AC transformer - 240V primary 12.8V secondary

[Matthew Kirkcaldie]

Hi all,

Having found an open primary in the small transformer providing standby
power to a Yamaha home theatre receiver, I want to source a replacement
of course.

The transformer is marked on the side:

XW608 AO
TAM M 0118

and has no voltage or power specs on it. On the schematic there is a
voltage shown across the secondary of 12.8V AC; the primary is 240VAC
since this is an Australian unit.

The transformer is physically small (about 30x30x30 mm, or roughly an
inch and a bit on each side) so I am guessing it has a rating in the
milliamp range for the standby switch, IR receiver and a relay to switch
on the main PSU.

Can anyone offer me guidance on sourcing a replacement? Searching for
the markings via Google hasn't turned up anything useful.

Thanks for any help,

Matthew.

 

[Matthew Kirkcaldie]

As a follow up, would this do if I can't get the same component?

http://www.jaycar.com.au/productView.asp?ID=MM2006

The output on the original is 12.8V but this is 12.6 - I don't know what
the tolerances are but I'm guessing it would be regulated in some way.

 

[Homer J Simpson]

As a follow up, would this do if I can't get the same component?

http://www.jaycar.com.au/productView.asp?ID=MM2006

The output on the original is 12.8V but this is 12.6 - I don't know what
the tolerances are but I'm guessing it would be regulated in some way.

Near enough. What about Dick Smiths?

 

[Phil Allison]

"Matthew Kirkcaldie"

As a follow up, would this do if I can't get the same component?

http://www.jaycar.com.au/productView.asp?ID=MM2006

The output on the original is 12.8V but this is 12.6 - I don't know what
the tolerances are but I'm guessing it would be regulated in some way.

** Looks ideal.

As would the similar DSE M2851

BTW both unit are made to " class 2 " or double insulation requirements.

Important if that Yamaha receiver is " class 2 " - as I bet it is.



..... Phil

 

[Matthew Kirkcaldie]

That's strange. Transformer primaries don't open very often. I would be
inclined to dig deeper to find out why there's an open circuit (internal
fuse open? Bad connection? Melted wire?) and whether there is any fault
downstream of the transformer (shorted component?).

Don't know the reason, but I have removed it from the board and there is
infinite resistance across the primary terminals and no visible damage
to the transformer or the board it's on. Fuse is intact. The unit
would be about 5-6 years old I reckon.

 

[Matthew Kirkcaldie]

As would the similar DSE M2851

BTW both unit are made to " class 2 " or double insulation requirements.

Important if that Yamaha receiver is " class 2 " - as I bet it is.

Thanks Phil - there's no ground on the plug so I would guess double
insulated is the way to go.

The DSE part is cheaper and available locally - thanks!

 

[James Sweet]

Hi all,

Having found an open primary in the small transformer providing standby
power to a Yamaha home theatre receiver, I want to source a replacement
of course.

The transformer is marked on the side:

XW608 AO
TAM M 0118

and has no voltage or power specs on it. On the schematic there is a
voltage shown across the secondary of 12.8V AC; the primary is 240VAC
since this is an Australian unit.

The transformer is physically small (about 30x30x30 mm, or roughly an
inch and a bit on each side) so I am guessing it has a rating in the
milliamp range for the standby switch, IR receiver and a relay to switch
on the main PSU.

Can anyone offer me guidance on sourcing a replacement? Searching for
the markings via Google hasn't turned up anything useful.

Thanks for any help,

Matthew.

Any small transformer with an approximately 12V output should be fine.

 

[James Sweet]

That's strange. Transformer primaries don't open very often. I would be
inclined to dig deeper to find out why there's an open circuit (internal
fuse open? Bad connection? Melted wire?) and whether there is any fault
downstream of the transformer (shorted component?).

Small transformers are impedance protected, the windings can be damaged
by power surges or an overloaded secondary. If the unit works after
replacing the transformer, it was probably just a surge that popped it.

 

[Rheilly Phoull]

Don't know the reason, but I have removed it from the board and there is
infinite resistance across the primary terminals and no visible damage
to the transformer or the board it's on. Fuse is intact. The unit
would be about 5-6 years old I reckon.

Mebbe it has a faulty or tripped thermal protector ?

 

[Jonno]

Mebbe it has a faulty or tripped thermal protector ?

Thermal protectors are fitted to prevent overheating etc. Usaully you
can by pass same, and "fix" them, but as theyre fitted for a reason( not
used to our extreme heat?) they often fail. The tranny suggested is
probly close enough.

 

[rebel]

Hi all,

Having found an open primary in the small transformer providing standby
power to a Yamaha home theatre receiver, I want to source a replacement
of course.

The transformer is marked on the side:

XW608 AO
TAM M 0118

and has no voltage or power specs on it. On the schematic there is a
voltage shown across the secondary of 12.8V AC; the primary is 240VAC
since this is an Australian unit.

The transformer is physically small (about 30x30x30 mm, or roughly an
inch and a bit on each side) so I am guessing it has a rating in the
milliamp range for the standby switch, IR receiver and a relay to switch
on the main PSU.

Can anyone offer me guidance on sourcing a replacement? Searching for
the markings via Google hasn't turned up anything useful.

The markings will be house numbering, either from Yamaha or their chinese part
supplier. The 0118 will be a date code - week (probably) 18 of 2001, and
googling that will not uncover anything helpful.

As others have said, any comparable unit with a 12v6 secondary will be fine.
Any downstream elctronics which are voltage sensitive will have some supply
regulation, to guard against mains input variation.

Apart from the Jaycar unit mentioned, Altronics have one which has dimensional
info at http://www.altronics.com.au/index.asp?area=item&id=M2851L.. 'tis a tad
weightier, implying to me that it has more iron or copper - both good things.

Even Trickie Dickie has one
http://www.dse.com.au/cgi-bin/dse.storefront/45e9221405120d9e2742c0a87f9c06b9/Product/View/M2851

Which one is for you depends on how critical size is, and how near you are to
the supplier.

 

[Matthew Kirkcaldie]

Almost certainly, replacing this tranny with a substitute, will cause no
problems at all, but I think that you should be aware of exactly what you
are doing for your own peace of mind. For what its worth, as a professional
repairer with a legal duty of care to the public, I would never substitute a
transformer that is going to run 24 hours a day, as a standby tranny is, nor
would I recommend others to do so. At the very least, I would try to check,
through the suppliers or even directly with the manufacturers, that any
tranny you intend to use is rated for continuous operation. I would also
contact a Yamaha spares agent to check the price and availability of a
genuine replacement, after you have proven that all is well by checking with
your substitute in place. Not trying to put you off or anything, just advice
...

Thanks Arfa, wise words there and I will certainly think it over.

 

[Phil Allison]

"Arfa Daily" = Dodgy Advice Par Excellence Merchant

That tranny will work just fine. The only thing that I would say is that
power transformers in domestic equipment are usually what's known as a
"designated safety component".

** In Class 2 equipment only - you PITA pommy panic merchant.

This means that they formed part of the original design approval which
declared the unit physically safe

** In Class 2 equipment only - you PITA pommy panic merchant.

- it won't set fire to your house in the event of it failing

** What does this paranoid know nothing fucking ASS imagine the damn AC
fuse is for .....

If you do substitute a non-Yamaha transformer for the original, this would
almost certainly compromise the original safety approvals for the
equipment,

** Only in Class 2 equipment - you PITA panic merchant.

Then only if the replacement is not a Class 2 compliant device.

Both the suggested subs ARE !!!!

and if there were any unforseen unfortunate consequences down the line,
Yamaha would have no liability at all.

** Yamaha supplied the POS that fucking failed - you dumb as dog shit
pommy ****.

Almost certainly, replacing this tranny with a substitute, will cause no
problems at all, but I think that you should be aware of exactly what you
are doing for your own peace of mind.

** Whaaaaaaaattt ??

This anonymous pommy **** is not balming anyone's piece of mind.

Cos the paranoid **** is damn well out of his !!!

For what its worth, as a professional repairer with a legal duty of care
to the public,

** Shame YOU have NO fucking idea what professionalism is all about.

Else you would not be posting such ** shite ** under a stupid pseudonym.

I would never substitute a transformer that is going to run 24 hours a
day, as a standby tranny is, nor would I recommend others to do so.

** That would be entirely because you are an autistic, knee trembling, know
nothing, fucking pile of pommy puke.

Well, at least tat is so on your good days .. ...

At the very least, I would try to check, through the suppliers or even
directly with the manufacturers, that any tranny you intend to use is
rated for continuous operation.

** LOL

Does so this annoynous PITA paranoid pommy **** have proof there are any
that are NOT ??

Won't hold my breath !!!

I would also contact a Yamaha spares agent to check the price and
availability of a genuine replacement, after you have proven that all is
well by checking with your substitute in place. Not trying to put you off
or anything, just advice

** Pile of ASD fucked, human garbage like " Arfur Daily" are regularly
taken out to a dark spot at night and kicked to death here in Australia

The decent blokes who do it deserve a medal.




........ Phil

 

[Phil Allison]

"Arfa Daily"

In my professional repair life,

** ROTFLMAO !!

What "professional life "' ?????????????

I replace trannies in hifi units all the time, that have primaries that
have gone open for no apparent reason.

** Well, there is always a simple reason for such events.

But nothing is "apparent " to a congenitally BRAIN DEAD **** !!.

Yes, sometimes there is a thermal fuse in the primary, and yes, sometimes
it's connected across a couple of external pins so can be temporarily
bridged for test purposes, but I find it rare to then come across a fault
downstream, that has caused a genuine overheat that has led to the
failure.

** LOL !!!!!!!!!!!!!!!!!

Might jus be becos the PROBLEM is UPSTREAM !!'

In the hands of the pommy IDIOT who owned and abused the stinking slope
head built POS.



.... Phil Allison

 

[Meat Plow]

Subject: Arfa Dialy = Scum of the Planet
From: "Phil Allison" <[email protected]>
Newsgroups: aus.electronics,sci.electronics.repair
Date: Sun, 4 Mar 2007 00:57:02 +1100


"Arfa Daily" = Dodgy Advice Par Excellence Merchant

Problem is, Arfa is right 99.9% of the time.

 

[Phil Allison]

"Meat Plow"

Problem is, Arfa is right 99.9% of the time.

** LOL - says who ???

Someone who is also wrong 99.9% of the time.




........ Phil

 

[Phil Allison]

"Arfa Daily"

Read properly what I said you half baked antipodean TWAT

** I did - asinine fools like you make me puke.

That tranny will work just fine. The only thing that I would say is that
power transformers in domestic equipment are usually what's known as a
"designated safety component".

** In Class 2 equipment only - you PITA pommy panic merchant.

This means that they formed part of the original design approval which
declared the unit physically safe

** In Class 2 equipment only - you PITA pommy panic merchant.

- it won't set fire to your house in the event of it failing

** What does this paranoid know nothing fucking ASS imagine the damn AC
fuse is for .....

If you do substitute a non-Yamaha transformer for the original, this would
almost certainly compromise the original safety approvals for the
equipment,

** Only in Class 2 equipment - you PITA panic merchant.

Then only if the replacement is not a Class 2 compliant device.

Both the suggested subs ARE !!!!
--------------------------------------

and if there were any unforseen unfortunate consequences down the line,
Yamaha would have no liability at all.

** Yamaha supplied the POS that fucking failed - you dumb as dog shit
pommy ****.

Almost certainly, replacing this tranny with a substitute, will cause no
problems at all, but I think that you should be aware of exactly what you
are doing for your own peace of mind.

** Whaaaaaaaattt ??

This anonymous pommy **** is not balming anyone's piece of mind.

Cos the paranoid **** is damn well out of his !!!

For what its worth, as a professional repairer with a legal duty of care
to the public,

** Shame YOU have NO fucking idea what professionalism is all about.

Else you would not be posting such ** shite ** under a stupid pseudonym.

I would never substitute a transformer that is going to run 24 hours a
day, as a standby tranny is, nor would I recommend others to do so.

** That would be entirely because you are an autistic, knee trembling, know
nothing, fucking pile of pommy puke.

Well, at least that is so on your good days ...

At the very least, I would try to check, through the suppliers or even
directly with the manufacturers, that any tranny you intend to use is
rated for continuous operation.

** LOL

Does so this anonymous PITA paranoid pommy **** have proof there are any
that are NOT so rated ??

Won't hold my breath !!!

I would also contact a Yamaha spares agent to check the price and
availability of a genuine replacement, after you have proven that all is
well by checking with your substitute in place. Not trying to put you off
or anything, just advice

** Pile of ASD fucked, human garbage like " Arfur Daily" are regularly
taken out to a dark spot at night and kicked to death here in Australia

The decent blokes who do it deserve a medal.



........ Phil

 

[Phil Allison]

"Arfa Daily Scum of the Planet MORON "



** Asinine fools like Daily make me wanna puke.

That tranny will work just fine. The only thing that I would say is that
power transformers in domestic equipment are usually what's known as a
"designated safety component".

** In Class 2 equipment only - you PITA pommy panic merchant.

This means that they formed part of the original design approval which
declared the unit physically safe

** In Class 2 equipment only - you PITA pommy panic merchant.

- it won't set fire to your house in the event of it failing

** What does this paranoid know nothing fucking ASS imagine the damn AC
fuse is for .....

If you do substitute a non-Yamaha transformer for the original, this would
almost certainly compromise the original safety approvals for the
equipment,

** Only in Class 2 equipment - you PITA panic merchant.

Then only if the replacement is not a Class 2 compliant device.

Both the suggested subs ARE !!!!
--------------------------------------

and if there were any unforseen unfortunate consequences down the line,
Yamaha would have no liability at all.

** Yamaha supplied the POS that fucking failed - you dumb as dog shit
pommy ****.

Almost certainly, replacing this tranny with a substitute, will cause no
problems at all, but I think that you should be aware of exactly what you
are doing for your own peace of mind.

** Whaaaaaaaattt ??

This anonymous pommy **** is not balming anyone's piece of mind.

Cos the paranoid **** is damn well out of his !!!

For what its worth, as a professional repairer with a legal duty of care
to the public,

** Shame YOU have NO fucking idea what professionalism is all about.

Else you would not be posting such ** shite ** under a stupid pseudonym.

I would never substitute a transformer that is going to run 24 hours a
day, as a standby tranny is, nor would I recommend others to do so.

** That would be entirely because you are an autistic, knee trembling, know
nothing, fucking pile of pommy puke.

Well, at least that is so on your good days ...

At the very least, I would try to check, through the suppliers or even
directly with the manufacturers, that any tranny you intend to use is
rated for continuous operation.

** LOL

Does so this anonymous PITA paranoid pommy **** have proof there are any
that are NOT so rated ??

Won't hold my breath !!!

I would also contact a Yamaha spares agent to check the price and
availability of a genuine replacement, after you have proven that all is
well by checking with your substitute in place. Not trying to put you off
or anything, just advice

** Pile of ASD fucked, human garbage like " Arfur Daily" are regularly
taken out to a dark spot at night and kicked to death here in Australia

The decent blokes who do it deserve a medal.


........ Phil

 

[Meat Plow]

"Meat Plow"



** LOL - says who ???

Someone who is also wrong 99.9% of the time.

Also meaning you included?

 

[Trevor Wilson]

Hi all,

Having found an open primary in the small transformer providing standby
power to a Yamaha home theatre receiver, I want to source a replacement
of course.

The transformer is marked on the side:

XW608 AO
TAM M 0118

and has no voltage or power specs on it. On the schematic there is a
voltage shown across the secondary of 12.8V AC; the primary is 240VAC
since this is an Australian unit.

The transformer is physically small (about 30x30x30 mm, or roughly an
inch and a bit on each side) so I am guessing it has a rating in the
milliamp range for the standby switch, IR receiver and a relay to switch
on the main PSU.

Can anyone offer me guidance on sourcing a replacement? Searching for
the markings via Google hasn't turned up anything useful.

**Yamaha are usually pretty helpful and not stupidly priced for spare parts.
Try them. The part will fit like a glove.