Hypex SMPS180 cooling & electrical safety confusion

[juggler]

Noob time, I'm afraid, and I know that what I'm doing is DIY assembly rather than designing and building an amp, but I'd be eternally grateful for any opinions from those more experienced.

I've been reading (and reading, and reading) and I'm about to assembly a Hypex UCD180HG+HxR based stereo amp with a single SMPS180 power supply.

StigErik and others have said that the SMPS180 runs very hot. I came across a design which mounted the heatsink of the PSU directly against a heatsink.. see http://www.ilikestyle.de/wp-content/...5/DSC_0096.jpg, and a number of others seem to have done the same.

However the Hypex docs say "This is a Safety Class 2 device. It is very important to maintain a 6mm clearance with all possible
conducting parts (housing etc.) and cables"

1. Is this approach safe? Does earthing the case make it safe?
2. If not - and the case has sufficient heatsinks - will mounting the PSU 10mm from all parts of the housing be ok without additional ventilation holes?

I would like to avoid drilling vent holes if possible.

thanks in advance

[marce]

You cannot do class 2 diy equipment, you cant test it reliably, so you will have to earth any exposed metal that may become live during a fault condition.
Personaly I think that Hypes are pushing the classification, I would not class it as a class 2 device, exposed metal that can be touched, and no double insulation.

[juggler]

Thanks for that - so the question remains: is this approach safe if the case is properly earthed?