is my PSU layout OK?

[tinkerbell]

hi all, this is my second power amp that i have ever built, and would like some comments on the PSU configuration (see picture)…

it is based on the 175w Jaycar modules Jaycar module

the PSU and amplifier are going to be in separate boxes, (to save space and ease portability)

my PSU will have two outputs of +/- 57V and two earths that will feed each of the two 175W boards.

the toroidals are 300VA with 40V windings, the caps are some stubby 15'000uF 80V ones i stumbled across, the regs are big 35A ones and the filtering will be mostly 0.1uF caps on the power rails.

it will be mounted on a 4mm thick 280x220 board.

does this look OK?

the 6 way terminal block will have 8ga leads to the amplifier unit of a max of 300mm length.

i am still trying to work out if i can have a safety feature on the flying 57v leads that only allows electricity to flow if it is connected at the amplifier end...

[Ultima Thule]

Any reason to spread out your transformers (eg. magnetic field)?

Do you perhaps have space to put the transformers on top of each other?

Don't forget to make a star-earth connection point!

Cheers

[peranders]

It doesn't harm at all to make the PS a bit more compact. Note also that your "regulators" are "rectifier bridges" and they must have some cooling if you want to take out more than 3-4 A continuously.

[tinkerbell]

yeah, the 'bridge rectifiers' (sorry!!!) will be mounted using dielectric grease to the 4mm thick 280x220mm aluminium base plate,

i hope this is enough of a sink for heat

'star earth' will be somewhere in the centre, i will have every earth and 0v line connected there, is that right?

the reason for the 'spread-out' transformers was basically due to aesthetics (it will have a perspex cover)

i did not think there would be any negative from this? i thought it would be better to keep both sides seperate...?

plus i want to keep it low profile (again for aethetics )

so you guys cant see any negatives with the layout?

thanks for the input

[costiss]

negative: non symmetrical power traces to each channel.. some advice: pay attention to your contacts..

[tinkerbell]

Originally posted by costiss
negative: non symmetrical power traces to each channel.. some advice: pay attention to your contacts..

but everything will be symmetrical? what are the non-symmetrical power traces?

i plan on hard soldering everything, are these the contacts that you might mean?

[mAJORD]

biggest problem i see is that i can't see how ur going to hook it up, do you want to maybe draw a connection diagram, im getting a sore head trying to guess where things are going

maybe its because i just got hm from work

[AndrewT]

Hi,
the two rectifiers should connect together to form a 0volt point. There are very large pulse currents running between the +caps and -caps to 0v do NOT take separate wires from each cap bank to ground. Instead take one wire from 0v to star ground, this isolates the dirty ground from the clean ground. When connecting the power amp to the PSU the dirty returns from all the onboard decoupling caps must be separate from the clean grounds to the signal returns.
Q1. do we need two ground returns from power amp to PSU, dirty and clean? or can they be tied at a local star ground?

[tinkerbell]

this is the circut diagram i followed for one channel of the power supply.

each of the two channels capacitor 0V's were going to join with the other side's 0v line at the star earth.

or should i have 1 star earth for each channel? is that what you mean?

i hope the pictures help!

[tinkerbell]

this is what the physical connections will look like: