XLR for DC voltages

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I happened to use a 4 pin xlr lately for a dual rail 5v supply,
pin 1 5v(1)
pin 2 0v(1)
pin 3 0v (2)
pin 4 5v (2)
Xlr sheild -screen
Its a dedicated supply with its own short cable , not designed to plug into anything else ,
who cares if we buck the 'convention' .
 
I have seen Sony video monitors with a 12VDC option for power (mobile use) that used a 4-pin XLR with a switch actuated by insertion of the XLR plug. I was a little surprised, but used that with an LCD monitor power brick until parts to repair the offline inverter arrived.

I have also seen desk lighting that used common 3-pin XLR for connecting to power brick. I was more surprised by that, but it must be common knowledge the contacts are substantial, and maybe there are current & voltage ratings in catalogs.

There was also no audio cabling anywhere nearby to be confused
 
A non 5 pin screw locking DIN configured so the fingers cant make contact with any live terminals might be ok ,
But the usual plastic Din plug should never be used for high voltage ,
Likewise cable strain relief , its worthless in the standard plastic/metal shell DIN plugs ,
not something you want with high voltages .
The clearances for high voltages between the pins of a DIN are probably a bit marginal by todays standards , probably fine for a tube mic , but for 300vdc , its a bit close.
Extra heatshrink around the solder points on the sockets and plugs is always a good thing , it acts like a strain relief of the individual conductors if the cables are ever moved around .

There was a question about clearances on HV traces on PCB's in another thread ,
I remember asking a buddy about a rotary mains switch I was using and if the clearances were upto modern spec , Its was a three position double wafer switch , so off, on(standby) and on(HT),
There was something like 2mm clearance between adjacent terminals on the switch with either mains voltage or AC straight off the HT winding ,
In the end I went with it despite the low clearance , its worked flawlessly for 20 years ,
 
Thank you tubetec, i think i’m going to use some industrial circular connectors, the problem that is a little bit hard to order the right mating socket and plug there is so much choice.
 
I use a 6 pin XLR for small mixers power consisting of HT, heaters and phantom power. BUT, you have to be careful which manufacturer of XLR you choose. Neutrik are not rated for high voltages or current but Amphenol are.

Cheers

Ian
 
I would NOT trust an aliexpress voltage rating

If you run HT in xlr's or the like, make sure to protect against charged-ht coming "back out" of the XLRM when cable is disconnected
 
i'm thinking to make an external box only for the trafos and the psu pcb inside the rack, i think it is safer and the voltages are lower.
i'll trust only mil spec amphenol socket but they are tooooo dear
 
I use a 6 pin XLR for small mixers
Which Amphenol series do you use ? I'm looking for suitable heater connector...
I only find the AC series with 6 or 7 pin, 133VRMS ?
But it's specified -Not suitable for domestic applications above 50V-

Cheers
Zam
 
Which Amphenol series do you use ? I'm looking for suitable heater connector...
I only find the AC series with 6 or 7 pin, 133VRMS ?
But it's specified -Not suitable for domestic applications above 50V-

Cheers
Zam
Yes, the AC series is what I use. 133V rms is 378V peak to peak so fine for 250V to 300V HT. Pro audio is not domestic use.

Cheers

Ian
 
Back in the 80s, I came up with the 5 pin XLR power that is used for most racks including the lunchbox. Pin 1 Chas, 2 gnd, 3 +v, 4 -v and 5 48v
I chose 5 pins because they can handle the current. I even use it for the power to my console buckets.
 
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