I have a safety question.
I want to keep the B+ PSU outside the case of a preamp I am building, so I found a PSU case that will sit on the floor and hold my 250V and 48V supply's. I plan on using the 48V for Phantom, and for tube heaters in series.
I realize the tube heater current is significant, so my cable will need to be substantial.
What I am concerned about is the connectors.
Can I use a 5 pin XLR connector (female of course) for the PSU or must I use some other connector?
Is there enough separation in a 5 Pin XLR for 250V?
Will 1 pin handle the heater current for 4 tubes (4 12V heaters in series)?
I plan on a pin out of:
1- Chassis
2- Ground
3- No Connection
4- +48V DC
5- +250V DC
Chassis and Ground will be joined in the PSU.
Pins 2 and 4 will have heavy conductors for the heater current.
Cable will be relatively short (3 feet maybe a little longer).
I plan on using Power One open frame PSU's fused in an IEC connector to mains power, and putting a fast blow 50mA fuse on the 250V DC circuit (4 tubes will probably consume 50mA of B+ or less) for safety. I will also fuse the 48V, but I imagine that will be a pretty high current fuse ( 300mA or so for 4 tubes in series approx. )
Is this a whacko idea?
What connector should I use instead of 5 pin XLR?
I don't want the PSU in the Preamp Case.
I plan on the PSU being able to supply 3 such preamps (3 separate 5 pin female xlr jacks)
Any advice would be appreciated.
(The current requirement seems reasonable as most of us with API racks are doing more current than that on the bipolar rails using 5 pin xlr, but I am worried about isolation of the 250V and any other safety suggestions).
I want to keep the B+ PSU outside the case of a preamp I am building, so I found a PSU case that will sit on the floor and hold my 250V and 48V supply's. I plan on using the 48V for Phantom, and for tube heaters in series.
I realize the tube heater current is significant, so my cable will need to be substantial.
What I am concerned about is the connectors.
Can I use a 5 pin XLR connector (female of course) for the PSU or must I use some other connector?
Is there enough separation in a 5 Pin XLR for 250V?
Will 1 pin handle the heater current for 4 tubes (4 12V heaters in series)?
I plan on a pin out of:
1- Chassis
2- Ground
3- No Connection
4- +48V DC
5- +250V DC
Chassis and Ground will be joined in the PSU.
Pins 2 and 4 will have heavy conductors for the heater current.
Cable will be relatively short (3 feet maybe a little longer).
I plan on using Power One open frame PSU's fused in an IEC connector to mains power, and putting a fast blow 50mA fuse on the 250V DC circuit (4 tubes will probably consume 50mA of B+ or less) for safety. I will also fuse the 48V, but I imagine that will be a pretty high current fuse ( 300mA or so for 4 tubes in series approx. )
Is this a whacko idea?
What connector should I use instead of 5 pin XLR?
I don't want the PSU in the Preamp Case.
I plan on the PSU being able to supply 3 such preamps (3 separate 5 pin female xlr jacks)
Any advice would be appreciated.
(The current requirement seems reasonable as most of us with API racks are doing more current than that on the bipolar rails using 5 pin xlr, but I am worried about isolation of the 250V and any other safety suggestions).