Same connectors for power and signal? That's going to end in sparks one day, really really bad idea. If the supply is high voltage DC you need to be aware that choosing the wrong connector could lead to flashover and fire - you really do have to take account of the ratings for connectors and know that DC is the worst case as arcs are not self-quenching with DC.
Connectors are always a bit of a headache, but this is not a good solution, certainly not Murphy's law compatible 🙂
No, they are only used for DC supply voltages as I wrote in my starter post. Moreover all those supply voltages are secured by fuses in the plus supply rail. And for risk of sparks: as I wrote in an earlier response I will heat shrink tubing every pin.
But anyway, I will replace them by proper SpeakOn connectors who have safe specifications. 🙂
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Like you i would not tolerate AC connection others than the one which are regulation compliants.
But guys, have you looked at pictures in first post?
JoeAlders talk about umbilical links from psu DC out to the gear not carrying mains supply ( if that had been the case i would have report and asked to delete the thread immediatly).
I'm not telling the situation is ideal far from it, but in some 'special' case it could be possible to do it that way:
_ tube microphone diy are usually powered this way using 7pin xlrs
_using heatshrink or other method to isolate tabs would add another layer of safety,
_ MAACO's advice to isolate the metal body's part with heatshrink is another safety layer which have to be implemented imho.
So now how i see situation if i try to take JoeAlders view:
He probably built the project without prototyping first and in the euphoria of the build had a very nice engraved case done for it.
Once done he faced the issue to find a connector type for the umbilical and at first sight XLR have desirable attribute: self locking, well built, easy to solder,...
Once holes cutted and everything assembled he discover some points which are problematic about the choice. What to do from there?
Changing connector type is an answer but it bring hassle : find something which would fit the actual cut, is availlable and don't cost an arm if possible.
Well industrial connectors can be an answer but if you are not a professional they don't meet the previous criteria (at least where i'm located, it might be different in other place).
From safety side there is no question this is what i would do and i'm sure once introduced to the risk this is probably what JoeAlders might came to same conclusion after a while ( i hope so).
Now what to do in the meantime? Discard the whole project? Find a temporary answer?
I'm for the second one .
My experience with B+ and XLR is that it can be used this way up to a limit which is defined by V and I of the circuit ( the load).
If the issue is for the 245V and 145V B+. Being an headphone amp i would expect them to be low but better have confirmation.
From there two options are possible, it is 'tolerable' for the connector and then we are back to evaluate another better solution but meanwhile enjoy the build being cautious about this.
Other solution it is not tolerable: discard connectors and hardwire the umbilical. This is the easiest, safest one. But it won't satisfy the eye.
In my view both will inevitably lead to a better answer to be found ( find a suitable industrial connector).
JoeAlders, not to be blunt, i had similar experience with some of my first built incorporating umbilical for tube circuits, so like you i learned it the hardway.
That said i find your attitude toward this situation very nice ( i was into deny when it happened to me... as it had to cost money i had'nt at that time) and your inquiry/search about datasheet have to be encouraged.
Being aware of a concern sometimes take time to accept it (to me).
Let's see how it turns and what is going to be your choice about it.
Edit: Powercon, not Speakon! Good choice in my view and wise decision from you. Thumb up!
But guys, have you looked at pictures in first post?
JoeAlders talk about umbilical links from psu DC out to the gear not carrying mains supply ( if that had been the case i would have report and asked to delete the thread immediatly).
I'm not telling the situation is ideal far from it, but in some 'special' case it could be possible to do it that way:
_ tube microphone diy are usually powered this way using 7pin xlrs
_using heatshrink or other method to isolate tabs would add another layer of safety,
_ MAACO's advice to isolate the metal body's part with heatshrink is another safety layer which have to be implemented imho.
So now how i see situation if i try to take JoeAlders view:
He probably built the project without prototyping first and in the euphoria of the build had a very nice engraved case done for it.
Once done he faced the issue to find a connector type for the umbilical and at first sight XLR have desirable attribute: self locking, well built, easy to solder,...
Once holes cutted and everything assembled he discover some points which are problematic about the choice. What to do from there?
Changing connector type is an answer but it bring hassle : find something which would fit the actual cut, is availlable and don't cost an arm if possible.
Well industrial connectors can be an answer but if you are not a professional they don't meet the previous criteria (at least where i'm located, it might be different in other place).
From safety side there is no question this is what i would do and i'm sure once introduced to the risk this is probably what JoeAlders might came to same conclusion after a while ( i hope so).
Now what to do in the meantime? Discard the whole project? Find a temporary answer?
I'm for the second one .
My experience with B+ and XLR is that it can be used this way up to a limit which is defined by V and I of the circuit ( the load).
If the issue is for the 245V and 145V B+. Being an headphone amp i would expect them to be low but better have confirmation.
From there two options are possible, it is 'tolerable' for the connector and then we are back to evaluate another better solution but meanwhile enjoy the build being cautious about this.
Other solution it is not tolerable: discard connectors and hardwire the umbilical. This is the easiest, safest one. But it won't satisfy the eye.
In my view both will inevitably lead to a better answer to be found ( find a suitable industrial connector).
JoeAlders, not to be blunt, i had similar experience with some of my first built incorporating umbilical for tube circuits, so like you i learned it the hardway.
That said i find your attitude toward this situation very nice ( i was into deny when it happened to me... as it had to cost money i had'nt at that time) and your inquiry/search about datasheet have to be encouraged.
Being aware of a concern sometimes take time to accept it (to me).
Let's see how it turns and what is going to be your choice about it.
Edit: Powercon, not Speakon! Good choice in my view and wise decision from you. Thumb up!
Another thing: i think i spotted you used female connectors on both side of your umbilical. If im not mistaken DON'T DO THAT either:
Having polarised/biased pin access to bare hands is asking for trouble: on the out of your psu side there should be female plate with male conector on your cable, this way there is no dc exposed pins to touch. 🙂
Take a look at a microphone cable and follow the way they are done, it is the safest one ( male on one side (connecting to female plate), female on the other (connecting to a male plate - on the gear psu input)...
That way at worst you could experience electrocution (from discharging capacitors... believe me it can hurt!) on the male plate but it is much less catastrophic than what could happen on a live psu.
Having polarised/biased pin access to bare hands is asking for trouble: on the out of your psu side there should be female plate with male conector on your cable, this way there is no dc exposed pins to touch. 🙂
Take a look at a microphone cable and follow the way they are done, it is the safest one ( male on one side (connecting to female plate), female on the other (connecting to a male plate - on the gear psu input)...
That way at worst you could experience electrocution (from discharging capacitors... believe me it can hurt!) on the male plate but it is much less catastrophic than what could happen on a live psu.
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Please always consult with a datasheet for your choice of connectors with regards to voltage, current ratings etc, Neutrik explicitly says for their XLR:
Rated voltage < 50 V
https://www.neutrik.com/en/product/nc3fp-1?c=audio
Rated voltage < 50 V
https://www.neutrik.com/en/product/nc3fp-1?c=audio