Spec'ing and switching a mains powered relay?

[Northy]

Hi all,

I'm building a DIY box with some pretty serious amp modules in it.

There will be two modules, with the spec:

100-240 V AC, 50-60Hz
AC Current Avg / Short Term: Nominal 4A / Max 25A
Inrush Current (230 V AC): 41A peak

I'd like a nice on/off switch on the front of the box.
I had a quick look (even though I imagined something wouldn't exist) for a power switch rated high enough and I couldn't see anything rated high enough for 2 x the above specs, or anything that really looked 'nice' at high current ratings.

So I had the idea of using a big relay?
I've never had to spec a relay to switch mains before, how much should it be over-rated for reliability?

Is there a pretty standard way to enable the relay that would allow the box to be turned fully off (0W power use), when it's off?
Could the mains be switched through a low power, nice looking switch to enable the high power relay that would power up the modules?

Thanks,

G

[Terry Bites]

Mains SS Relays generate a lot of hash.
Mechanical with mains coil will buzz a little
How are you going to control your relay AC/DC LV, Mains?
There's no cheap way. Use a  contactor and put poles in parallel- with snubber!
If you don't use a snubber you are going to severely shorten the contact life.
https://www.tlc-direct.co.uk/Products/CMREL230slash25slash40.html
https://components.omron.com/relay-basics/general-app

[Northy]

I hadn't worked out how I was going to control the relay yet, I was wondering if there was a way to do it where the unit would truly use zero power when switched off, so by enabling the relay with mains through a lower rated switch on the front panel?
Is that possible?

What sort of snubber would you suggest?

Thanks,

G

[NiHaoMike]

Could use a DC relay with a capacitive power supply to run the coil.

If you can modify or slightly redesign the power supply, you could have the switch disconnect the startup resistor and signal the controller to turn off the output?

[Northy]

If you can modify or slightly redesign the power supply, you could have the switch disconnect the startup resistor and signal the controller to turn off the output?

Do you mean by putting the modules into a low power/sleep mode?
Unfortunately they still use significant power in that mode and my conscience would rather a true zero power off - we've got to be green these days haven't we? 

Thanks,

G