Chaining PSU's

[daArry]

Hey,

SO I've decided it best to leave the psu's for the yamaha desk I'm reworking outside the chassis to allow more room for other goodies...

As I'm using another seperate psu for the the digital ckts (+5V/+12V) as well as the original yam psu for analog supplies - how is it best to link them both back to a single IEC socket/power switch? The reason I'm unsure is because there's gonna be a good few amps running in this beast and I'm wondering about what current rating the main power connector, switch, fuse n whatnot should be...

Digital supply is a nice switcher I picked up and is rated at 8A alone. This should be fine for eventually this box will have motorfaders, lcds (and other midibox stuff) plus the relays will be run of the +5 too. The analog supply seems ample too - 2x +15/-15V, 1x +48V 1x 10VAC. I think this is rated around 4A (sounds about right for a 24 desk right?)...

I was planning on using a 3pin XLR for digital psu connection between psu and desk and a 5pin XLR for analog supply (just need the 15's)...

Am okay with a regular IEC socket and DPDT power switch (connected to each psu's N input)?

Cheers!

 

[Guest]

DeArry
I was thinking about using 3 pin XLRs - but decided against it and used 4 pin XLRs...
I can just imagine myself pluggin a micinto it...

 

[BradAvenson]

Check out the speakon connectors for power. Nice big locking, could be the way to go, I think they have an 8 pin version.

 

[daArry]

Cheers...I found some suitable chunky locking sockets for the power connections between the main psu box and mixer. The digital supply will be on a 4 pole connector and carry +5, +12 and DGND via 3 core cable. The analog supply will be on a 8 pole connector and carry 2x +15, 2x -15, 48V, AGND, and 10VAC. For the multi-core cable needed I was gonna make some up with suitable insulated cable...The 10VAC wires i was gonna twist seperate from the other DC voltages then heatshrink that bundle together - is that alright? cable length will be a cpl of meters...

As the 2 psu's have theyre grounds seperate (agnd/dgnd respectivly) and are not connected anywhere (neither connected to chassis also) would this pose any forseeable probs?

For connecting the 2 supplies back to a single powerswitch/fuse/iec I found a 14A rated dpst switch and fused type 10A rated IEC connector - just to be clear, was planning to hook it all up like this:

What rating fuse should I run with there - a cpl amps dandy?

Thanks![/img]

 

[Guest]

daArry
Watching with interest
In a previous reply CJ noted to put 1 fuse at the inlet and an extra one one on the secondary primary (for each PSU)
I am doing it by having a little home etched PCB that takes the live and neutral from the IEC and splits it into 3 different outputs
Mounted four screw terminals on the PCB (one for input, three for output)
Then took the three outputs of live and neutral (six wires) into three separate DPST switches on the front and from there to the three PSUs
Note - on my PSUs I don;t have any fuses - I just rely on the IEC fuse (maybe a bad thing)
So each PSU could be switched on/off...
In addition each PSU has a LED out just before the DC outs - this then goes to the panel next to the relevant DPST switch
But - I could be wrong - I am just a total beginner
Interesting point about what fuse to put into the IEC inlet...

 

[Mendelt]

I've seen special connectors for power that have one longer pin for earth so you will allways connect earth first. That way you won't blow stuff up when for example there's static electricity on the housing of your board. I'd try to find something like that