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Mains transformer blew up amplifier, incorrect description in wiring instructions?
Transformer pri windingHow can I find out which wires are the primary wires on this transformer?How does this mosquito zapper circuit work?Wiring a step down transformerIdentifying this "IC”, Trying to reverse engineer a boardTransformer Problem DiagnosisTransformer has continuity but no power on secondary coilHow to connect toroidal transformer from wall powerTransformer identification neededTransfromer from an old inverter
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$begingroup$
I am assembling a power amplifier from a kit I purchased from Velleman (Module: VM100). With the amplifier I purchased this mains toroidal transformer - .
The amplifier came with these instructions:

Here is a photo of the PCB, you can see the male connectors are labelled as such (the manual states Y: yellow, R: Red, B: Blue, G: Grey):

- Yellow : 25-30V AC
- Red : AC-0
- Grey : 25-30V AC-0
- Blue : AC
I connected the transformer as described, however when I powered up the transformer the amp blew up. I suspect this is because I have connected the transformer to the amplifier incorrectly, and on closer inspection of the Transformer I found the following wire labelling:

Pri:
- 0.....240V 50-60Hz (Brown Blue)
Sec:
- 0.....30V-2A (Red Yellow)
- 0.....30V-2A (Black Grey)
If I am reading this correctly I should have connected this transformer to the PCB is as follows:
Connect the following wires to mains:
- Brown = 0V (Neutral wire)
- Blue = 240V (Live wire)
And the following to the PCB:
- Red = AC-0
- Yellow = 25-30V AC
- Grey = 25-30V AC-0
Black = AC (not Blue = AC)
Is this new reconfiguration correct?
amplifier transformer mains toroid
New contributor
Harley Morlet is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$endgroup$
|
show 1 more comment
$begingroup$
I am assembling a power amplifier from a kit I purchased from Velleman (Module: VM100). With the amplifier I purchased this mains toroidal transformer - .
The amplifier came with these instructions:

Here is a photo of the PCB, you can see the male connectors are labelled as such (the manual states Y: yellow, R: Red, B: Blue, G: Grey):

- Yellow : 25-30V AC
- Red : AC-0
- Grey : 25-30V AC-0
- Blue : AC
I connected the transformer as described, however when I powered up the transformer the amp blew up. I suspect this is because I have connected the transformer to the amplifier incorrectly, and on closer inspection of the Transformer I found the following wire labelling:

Pri:
- 0.....240V 50-60Hz (Brown Blue)
Sec:
- 0.....30V-2A (Red Yellow)
- 0.....30V-2A (Black Grey)
If I am reading this correctly I should have connected this transformer to the PCB is as follows:
Connect the following wires to mains:
- Brown = 0V (Neutral wire)
- Blue = 240V (Live wire)
And the following to the PCB:
- Red = AC-0
- Yellow = 25-30V AC
- Grey = 25-30V AC-0
Black = AC (not Blue = AC)
Is this new reconfiguration correct?
amplifier transformer mains toroid
New contributor
Harley Morlet is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$endgroup$
$begingroup$
Can you specify more about what blew up?
$endgroup$
– RobinSt
5 hours ago
1
$begingroup$
WARNING you have reversed Live and Neutral in the above. Live is brown, Neutral is blue.
$endgroup$
– Brian Drummond
4 hours ago
$begingroup$
@RobinSt The amplifier PCB initially worked however after a minute the components begun to burn
$endgroup$
– Harley Morlet
3 hours ago
$begingroup$
@BrianDrummond I was aware of this when I wrote the comment, however as described on the transformer (0.....240V 50-60Hz (Brown Blue)). Does this not imply that Brown is the Neutral?
$endgroup$
– Harley Morlet
3 hours ago
1
$begingroup$
No. See EU colour code.
$endgroup$
– Brian Drummond
3 hours ago
|
show 1 more comment
$begingroup$
I am assembling a power amplifier from a kit I purchased from Velleman (Module: VM100). With the amplifier I purchased this mains toroidal transformer - .
The amplifier came with these instructions:

Here is a photo of the PCB, you can see the male connectors are labelled as such (the manual states Y: yellow, R: Red, B: Blue, G: Grey):

- Yellow : 25-30V AC
- Red : AC-0
- Grey : 25-30V AC-0
- Blue : AC
I connected the transformer as described, however when I powered up the transformer the amp blew up. I suspect this is because I have connected the transformer to the amplifier incorrectly, and on closer inspection of the Transformer I found the following wire labelling:

Pri:
- 0.....240V 50-60Hz (Brown Blue)
Sec:
- 0.....30V-2A (Red Yellow)
- 0.....30V-2A (Black Grey)
If I am reading this correctly I should have connected this transformer to the PCB is as follows:
Connect the following wires to mains:
- Brown = 0V (Neutral wire)
- Blue = 240V (Live wire)
And the following to the PCB:
- Red = AC-0
- Yellow = 25-30V AC
- Grey = 25-30V AC-0
Black = AC (not Blue = AC)
Is this new reconfiguration correct?
amplifier transformer mains toroid
New contributor
Harley Morlet is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$endgroup$
I am assembling a power amplifier from a kit I purchased from Velleman (Module: VM100). With the amplifier I purchased this mains toroidal transformer - .
The amplifier came with these instructions:

Here is a photo of the PCB, you can see the male connectors are labelled as such (the manual states Y: yellow, R: Red, B: Blue, G: Grey):

- Yellow : 25-30V AC
- Red : AC-0
- Grey : 25-30V AC-0
- Blue : AC
I connected the transformer as described, however when I powered up the transformer the amp blew up. I suspect this is because I have connected the transformer to the amplifier incorrectly, and on closer inspection of the Transformer I found the following wire labelling:

Pri:
- 0.....240V 50-60Hz (Brown Blue)
Sec:
- 0.....30V-2A (Red Yellow)
- 0.....30V-2A (Black Grey)
If I am reading this correctly I should have connected this transformer to the PCB is as follows:
Connect the following wires to mains:
- Brown = 0V (Neutral wire)
- Blue = 240V (Live wire)
And the following to the PCB:
- Red = AC-0
- Yellow = 25-30V AC
- Grey = 25-30V AC-0
Black = AC (not Blue = AC)
Is this new reconfiguration correct?
amplifier transformer mains toroid
amplifier transformer mains toroid
New contributor
Harley Morlet is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
New contributor
Harley Morlet is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
edited 5 hours ago
Harley Morlet
New contributor
Harley Morlet is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 7 hours ago
Harley MorletHarley Morlet
134
134
New contributor
Harley Morlet is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
New contributor
Harley Morlet is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
Harley Morlet is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$begingroup$
Can you specify more about what blew up?
$endgroup$
– RobinSt
5 hours ago
1
$begingroup$
WARNING you have reversed Live and Neutral in the above. Live is brown, Neutral is blue.
$endgroup$
– Brian Drummond
4 hours ago
$begingroup$
@RobinSt The amplifier PCB initially worked however after a minute the components begun to burn
$endgroup$
– Harley Morlet
3 hours ago
$begingroup$
@BrianDrummond I was aware of this when I wrote the comment, however as described on the transformer (0.....240V 50-60Hz (Brown Blue)). Does this not imply that Brown is the Neutral?
$endgroup$
– Harley Morlet
3 hours ago
1
$begingroup$
No. See EU colour code.
$endgroup$
– Brian Drummond
3 hours ago
|
show 1 more comment
$begingroup$
Can you specify more about what blew up?
$endgroup$
– RobinSt
5 hours ago
1
$begingroup$
WARNING you have reversed Live and Neutral in the above. Live is brown, Neutral is blue.
$endgroup$
– Brian Drummond
4 hours ago
$begingroup$
@RobinSt The amplifier PCB initially worked however after a minute the components begun to burn
$endgroup$
– Harley Morlet
3 hours ago
$begingroup$
@BrianDrummond I was aware of this when I wrote the comment, however as described on the transformer (0.....240V 50-60Hz (Brown Blue)). Does this not imply that Brown is the Neutral?
$endgroup$
– Harley Morlet
3 hours ago
1
$begingroup$
No. See EU colour code.
$endgroup$
– Brian Drummond
3 hours ago
$begingroup$
Can you specify more about what blew up?
$endgroup$
– RobinSt
5 hours ago
$begingroup$
Can you specify more about what blew up?
$endgroup$
– RobinSt
5 hours ago
1
1
$begingroup$
WARNING you have reversed Live and Neutral in the above. Live is brown, Neutral is blue.
$endgroup$
– Brian Drummond
4 hours ago
$begingroup$
WARNING you have reversed Live and Neutral in the above. Live is brown, Neutral is blue.
$endgroup$
– Brian Drummond
4 hours ago
$begingroup$
@RobinSt The amplifier PCB initially worked however after a minute the components begun to burn
$endgroup$
– Harley Morlet
3 hours ago
$begingroup$
@RobinSt The amplifier PCB initially worked however after a minute the components begun to burn
$endgroup$
– Harley Morlet
3 hours ago
$begingroup$
@BrianDrummond I was aware of this when I wrote the comment, however as described on the transformer (0.....240V 50-60Hz (Brown Blue)). Does this not imply that Brown is the Neutral?
$endgroup$
– Harley Morlet
3 hours ago
$begingroup$
@BrianDrummond I was aware of this when I wrote the comment, however as described on the transformer (0.....240V 50-60Hz (Brown Blue)). Does this not imply that Brown is the Neutral?
$endgroup$
– Harley Morlet
3 hours ago
1
1
$begingroup$
No. See EU colour code.
$endgroup$
– Brian Drummond
3 hours ago
$begingroup$
No. See EU colour code.
$endgroup$
– Brian Drummond
3 hours ago
|
show 1 more comment
1 Answer
1
active
oldest
votes
$begingroup$
You are correct in what you have determined, the connections should be wired as you have described and not per the documentation. The only exception would be to use brown for live and blue for neutral to conform with wiring standards.
The transformer you are using is different from the one they have picture/documented, in that the black and blue wires have swapped purposes.
As a word of caution to others finding this question: the manual does state to be careful of different colour schemes.

The net result is you will have connected mains directly to the amplifier, most likely destroying some or all of the circuit.
$endgroup$
$begingroup$
Thank you for your answer, much appreciated. My mistake was to assume I could follow the instructions directly as I purchased both items from Velleman. I clearly should have confirmed the wiring of the transformer this before following blindly.
$endgroup$
– Harley Morlet
3 hours ago
$begingroup$
How is heat transferred to the heatsink? is any thermal compound used?
$endgroup$
– analogsystemsrf
1 hour ago
$begingroup$
yes there is a small amount of thermal compound used, why do you ask?
$endgroup$
– Harley Morlet
1 hour ago
add a comment |
Your Answer
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
$begingroup$
You are correct in what you have determined, the connections should be wired as you have described and not per the documentation. The only exception would be to use brown for live and blue for neutral to conform with wiring standards.
The transformer you are using is different from the one they have picture/documented, in that the black and blue wires have swapped purposes.
As a word of caution to others finding this question: the manual does state to be careful of different colour schemes.

The net result is you will have connected mains directly to the amplifier, most likely destroying some or all of the circuit.
$endgroup$
$begingroup$
Thank you for your answer, much appreciated. My mistake was to assume I could follow the instructions directly as I purchased both items from Velleman. I clearly should have confirmed the wiring of the transformer this before following blindly.
$endgroup$
– Harley Morlet
3 hours ago
$begingroup$
How is heat transferred to the heatsink? is any thermal compound used?
$endgroup$
– analogsystemsrf
1 hour ago
$begingroup$
yes there is a small amount of thermal compound used, why do you ask?
$endgroup$
– Harley Morlet
1 hour ago
add a comment |
$begingroup$
You are correct in what you have determined, the connections should be wired as you have described and not per the documentation. The only exception would be to use brown for live and blue for neutral to conform with wiring standards.
The transformer you are using is different from the one they have picture/documented, in that the black and blue wires have swapped purposes.
As a word of caution to others finding this question: the manual does state to be careful of different colour schemes.

The net result is you will have connected mains directly to the amplifier, most likely destroying some or all of the circuit.
$endgroup$
$begingroup$
Thank you for your answer, much appreciated. My mistake was to assume I could follow the instructions directly as I purchased both items from Velleman. I clearly should have confirmed the wiring of the transformer this before following blindly.
$endgroup$
– Harley Morlet
3 hours ago
$begingroup$
How is heat transferred to the heatsink? is any thermal compound used?
$endgroup$
– analogsystemsrf
1 hour ago
$begingroup$
yes there is a small amount of thermal compound used, why do you ask?
$endgroup$
– Harley Morlet
1 hour ago
add a comment |
$begingroup$
You are correct in what you have determined, the connections should be wired as you have described and not per the documentation. The only exception would be to use brown for live and blue for neutral to conform with wiring standards.
The transformer you are using is different from the one they have picture/documented, in that the black and blue wires have swapped purposes.
As a word of caution to others finding this question: the manual does state to be careful of different colour schemes.

The net result is you will have connected mains directly to the amplifier, most likely destroying some or all of the circuit.
$endgroup$
You are correct in what you have determined, the connections should be wired as you have described and not per the documentation. The only exception would be to use brown for live and blue for neutral to conform with wiring standards.
The transformer you are using is different from the one they have picture/documented, in that the black and blue wires have swapped purposes.
As a word of caution to others finding this question: the manual does state to be careful of different colour schemes.

The net result is you will have connected mains directly to the amplifier, most likely destroying some or all of the circuit.
edited 2 hours ago
answered 5 hours ago
Tom CarpenterTom Carpenter
40.1k375121
40.1k375121
$begingroup$
Thank you for your answer, much appreciated. My mistake was to assume I could follow the instructions directly as I purchased both items from Velleman. I clearly should have confirmed the wiring of the transformer this before following blindly.
$endgroup$
– Harley Morlet
3 hours ago
$begingroup$
How is heat transferred to the heatsink? is any thermal compound used?
$endgroup$
– analogsystemsrf
1 hour ago
$begingroup$
yes there is a small amount of thermal compound used, why do you ask?
$endgroup$
– Harley Morlet
1 hour ago
add a comment |
$begingroup$
Thank you for your answer, much appreciated. My mistake was to assume I could follow the instructions directly as I purchased both items from Velleman. I clearly should have confirmed the wiring of the transformer this before following blindly.
$endgroup$
– Harley Morlet
3 hours ago
$begingroup$
How is heat transferred to the heatsink? is any thermal compound used?
$endgroup$
– analogsystemsrf
1 hour ago
$begingroup$
yes there is a small amount of thermal compound used, why do you ask?
$endgroup$
– Harley Morlet
1 hour ago
$begingroup$
Thank you for your answer, much appreciated. My mistake was to assume I could follow the instructions directly as I purchased both items from Velleman. I clearly should have confirmed the wiring of the transformer this before following blindly.
$endgroup$
– Harley Morlet
3 hours ago
$begingroup$
Thank you for your answer, much appreciated. My mistake was to assume I could follow the instructions directly as I purchased both items from Velleman. I clearly should have confirmed the wiring of the transformer this before following blindly.
$endgroup$
– Harley Morlet
3 hours ago
$begingroup$
How is heat transferred to the heatsink? is any thermal compound used?
$endgroup$
– analogsystemsrf
1 hour ago
$begingroup$
How is heat transferred to the heatsink? is any thermal compound used?
$endgroup$
– analogsystemsrf
1 hour ago
$begingroup$
yes there is a small amount of thermal compound used, why do you ask?
$endgroup$
– Harley Morlet
1 hour ago
$begingroup$
yes there is a small amount of thermal compound used, why do you ask?
$endgroup$
– Harley Morlet
1 hour ago
add a comment |
Harley Morlet is a new contributor. Be nice, and check out our Code of Conduct.
Harley Morlet is a new contributor. Be nice, and check out our Code of Conduct.
Harley Morlet is a new contributor. Be nice, and check out our Code of Conduct.
Harley Morlet is a new contributor. Be nice, and check out our Code of Conduct.
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$begingroup$
Can you specify more about what blew up?
$endgroup$
– RobinSt
5 hours ago
1
$begingroup$
WARNING you have reversed Live and Neutral in the above. Live is brown, Neutral is blue.
$endgroup$
– Brian Drummond
4 hours ago
$begingroup$
@RobinSt The amplifier PCB initially worked however after a minute the components begun to burn
$endgroup$
– Harley Morlet
3 hours ago
$begingroup$
@BrianDrummond I was aware of this when I wrote the comment, however as described on the transformer (0.....240V 50-60Hz (Brown Blue)). Does this not imply that Brown is the Neutral?
$endgroup$
– Harley Morlet
3 hours ago
1
$begingroup$
No. See EU colour code.
$endgroup$
– Brian Drummond
3 hours ago