Efficient/safe way to power rack units

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Efficient/safe way to power rack units

Post by richkeyworth »

Hello,

I've got a rack with 6 units (3 FX, 2 preamps and interface) in it, and I'm wondering if it's time I consider powering it in a better way, especially as it might expand to include a few more units.
Currently everything is plugged into an extension cable which is daisy-chained into another one, which is less than ideal but necessary given the limited mains sockets in my studio room.

I've read conflicting things about power conditioners; some say they're not at all necessary, some swear by them. I'm looking for some peace of mind regarding power surges, and a way to ensure noise is kept to minimum.

If anyone has any advice, please let me know!

Thanks
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Re: Efficient/safe way to power rack units

Post by Wonks »

Hi and welcome.

Where are you in the world? If you are in the UK, where the mains electricity is good quality, then power conditioners do nothing for you. They may (no guarantees) stop a large voltage spike caused by a nearby fault on the distribution network, but otherwise, zero.

In the US with generally poorer quality mains power supply, they can provide some benefit.

But you are best off first ensuring that all your power sockets are correctly wired and your ground connections have a low impedance to earth.

Noisy equipment is normally a result of local interference e.g. in-line PSU with a transformer right next to a rack unit, or ground loops.

Star-connecting extension sockets is a good way to minimise ground loops, e.g. 1x4 way powering four x 6-way sockets. Obviously you need to keep track of current draw, but most rack equipment apart from power amps has pretty minimal power requirements.

The only thing to watch out for with feeding a lot of equipment from one wall power socket is that inrush current on power-up can be a lot higher than the steady state current and if you just use the wall socket's power switch (if it has one) to turn everything on and off, it can burn out over time.
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Re: Efficient/safe way to power rack units

Post by Hugh Robjohns »

It partly depends on the quality and stability of your mains supply.

In the UK a power conditioner isn't really necessary, but they remain popular as a convenient way of powering multiple units, and because of the handy rack lights :-D

Personally, I generally just bolt a rack mounting mains distribution unit into the rear of the rack and power everything from that. You can get them with 6 or 8 (13A) mains sockets, or more IEC outlets.

H
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Re: Efficient/safe way to power rack units

Post by richkeyworth »

Wonks wrote: Sat Jan 15, 2022 5:06 pm Hi and welcome.

Where are you in the world? If you are in the UK, where the mains electricity is good quality, then power conditioners do nothing for you. They may (no guarantees) stop a large voltage spike caused by a nearby fault on the distribution network, but otherwise, zero.

In the US with generally poorer quality mains power supply, they can provide some benefit.

But you are best off first ensuring that all your power sockets are correctly wired and your ground connections have a low impedance to earth.

Noisy equipment is normally a result of local interference e.g. in-line PSU with a transformer right next to a rack unit, or ground loops.

Star-connecting extension sockets is a good way to minimise ground loops, e.g. 1x4 way powering four x 6-way sockets. Obviously you need to keep track of current draw, but most rack equipment apart from power amps has pretty minimal power requirements.

The only thing to watch out for with feeding a lot of equipment from one wall power socket is that inrush current on power-up can be a lot higher than the steady state current and if you just use the wall socket's power switch (if it has one) to turn everything on and off, it can burn out over time.

Thank you! I'm in the UK, so that's good to know.

Apologies but I'm not quite sure what you mean by star-connecting, please explain? My knowledge of electronics is embarrassingly basic to say the least.

Hugh Robjohns wrote: Sat Jan 15, 2022 5:14 pm It partly depends on the quality and stability of your mains supply.

In the UK a power conditioner isn't really necessary, but they remain popular as a convenient way of powering multiple units, and because of the handy rack lights :-D

Personally, I generally just bolt a rack mounting mains distribution unit into the rear of the rack and power everything from that. You can get them with 6 or 8 (13A) mains sockets, or more IEC outlets.

H

Thanks Hugh. As far as I'm aware our mains supply is fine - I've yet to have any reason to think otherwise. Fingers crossed it stays that way!

About the mains distribution unit; does this also provide surge protection? I've just bought a nice preamp and I'm a little concerned (or paranoid) about a power surge potentially blowing it up. Which one do you have, if you don't mind my asking?

Thanks
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Re: Efficient/safe way to power rack units

Post by Hugh Robjohns »

Star distribution

Image

I use rackmount mains units made by Pulse, sold through CPC (amongst others). The particular units i use have surge protection, but not all do. There are other models with IEC outlets if you prefer that.

Image

https://cpc.farnell.com/pulse/pds6-srg/ ... dp/DP36295
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Re: Efficient/safe way to power rack units

Post by richkeyworth »

Hugh Robjohns wrote: Sat Jan 15, 2022 5:54 pm Star distribution

Image

I use rackmount mains units made by Pulse, sold through CPC (amongst others). The particular units i use have surge protection, but not all do. There are other models with IEC outlets if you prefer that.

Image

https://cpc.farnell.com/pulse/pds6-srg/ ... dp/DP36295

Thanks Hugh, that looks like just the sort of thing I need
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Re: Efficient/safe way to power rack units

Post by Hugh Robjohns »

You can use the switch to power the whole rack on-off if you want, and there is a removable cover to prevent accidental powering if preferred.

I prefer to install the power board at the top rear of a rack, but if you have space it can go on the front (I'd put it near the bottom with space below to run the cables through).

If you have multiple racks or other gear, to power, run them back to another plugboard in the star arrangement shown above.
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Re: Efficient/safe way to power rack units

Post by richkeyworth »

Thanks Hugh, that's really helpful!
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