Typical Power Requirements

[scalpy]

Hi all

 

Often my function band gets asked for its power requirements at a venue. Not being electrically minded at all, what is a reasonable response? Safe doesn’t seem to cut it!

 

We’re 8-12 piece, running a 3k Pa, medium size led lighting rig and an in ears rack.

 

Any help would be most appreciated.

 

Thank you

 

Harry

 

[Dad3353]

You'll have to list all of your backline amps, and what LED projectors you have, to get a reasonable answer. Best guess from me would be 'less than 10kW', if you're not using valve amps and only LED PARs. The venue want to know if their power sockets and fuse boxes can support your equipment safely. In days of yore, with Genie tower lighting rigs and multi-head guitar and bass stacks, special power outlets were required. If you're below 10kW you should be OK using domestic power outlets. Hope this helps. 

Disclaimer : subject to completion, correction and/or contradiction from others.

Edited July 4, 2023 by Dad3353

[Steve Browning]

I understand (for amps) it's RMS output/volts. 

[Dad3353]

Just now, Steve Browning said:

I understand (for amps) it's RMS output/volts. 

 

Amps will have a sticker or plate on the back, somewhere, indicating the power draw from the venue. It's not the same as the rated 'watts' of the amp. No calculation required; simply add up all the wattage from all those stickers and plates. Tell the venue what that wattage is. Dividing by 220 will give the amperage needed; should be below 10A, ideally. 

[Suburban Man]

23 minutes ago, Dad3353 said:

 

Amps will have a sticker or plate on the back, somewhere, indicating the power draw from the venue. It's not the same as the rated 'watts' of the amp. No calculation required; simply add up all the wattage from all those stickers and plates. Tell the venue what that wattage is. Dividing by 220 will give the amperage needed; should be below 10A, ideally. 

All good stuff from Dad.  Your 3kW PA system should (just) work off a standard domestic 13A outlet (13A x 230V = 2.9kW) but would probably be better being fed from a 16A unfused socket. The In Ears rack will probably draw a fraction of an amp, so its down to the amount of backline that you carry and your lighting which as Dad says, you just have to add up to get a grand total. I don't know how you usually plug into the venue power system but a 'pro' electrical solution would be a couple of those big blue 16A BS4343 plugs - often known as 'Commando Plugs' - which have the advantage of not containing fuses. One for the PA, one for everything else.  Might be overkill for some venues however...

[Dad3353]

14 minutes ago, Suburban Man said:

... those big blue 16A BS4343 plugs - often known as 'Commando Plugs' ...

 

Quite certainly overkill for pub gigs; there are very few equipped in such a way, I'd say. Concert halls, theatre stages and festivals, certainly, but not much elsewhere. 

[Happy Jack]

500+ gigs at pubs, clubs & festivals, playing with everything from 3-piece to 8-piece bands and we've never yet needed more than a single 13A domestic socket.

 

That's backline, PA and lights.

 

I realise that other, bigger bands may well have greater demands, but at the pub/club level it's very rare to need anything special. 

 

IMHO

 

[scalpy]

3 hours ago, Dad3353 said:

You'll have to list all of your backline amps, and what LED projectors you have, to get a reasonable answer. Best guess from me would be 'less than 10kW', if you're not using valve amps and only LED PARs. The venue want to know if their power sockets and fuse boxes can support your equipment safely. In days of yore, with Genie tower lighting rigs and multi-head guitar and bass stacks, special power outlets were required. If you're below 10kW you should be OK using domestic power outlets. Hope this helps. 

Disclaimer : subject to completion, correction and/or contradiction from others.

Thank you all

 

No backline and no amps apart from the PA. 
 

We’ve run the whole kaboodle comfortably from 2 domestic sockets- just don’t know what figure to put on that. Will have to get to the lock up with pen, paper and calculator by the sounds of it! 
 

Harry

[itu]

My experience has been that a burnt breaker is very rare. Maybe two, three times, but then the electricity has been questionable. I have played maybe +1500 gigs and far more rehearsals. Of course any suspect unit can kill a breaker, but that usually happens in a soundcheck.

 

At the moment I play in a band with 2 x JBL PRX735 (1.5 kW/side) after a U24i, a tube g-amp (12 or 50 W), piano, a Glockenklang Soul (450 W). On top of that, half a dozen LEDs. A quick calculation gives +3500 W (full power including LEDs), and that is around 16 A. But there's no need to drive the set so loud. The max RMS power taken from the line is probably closer to 20 % of the max = 2 - 4 A.

 

I think this should be measured some time...

[Suburban Man]

1 hour ago, scalpy said:

Thank you all

 

No backline and no amps apart from the PA. 
 

We’ve run the whole kaboodle comfortably from 2 domestic sockets- just don’t know what figure to put on that. Will have to get to the lock up with pen, paper and calculator by the sounds of it! 
 

Harry

Well, you know that your 3kW PA will work off one 13A outlet, so if you just say - 'we need Two 13A outlets' - then I would have thought that should be enough for most venues.  If they say 'How many kW' then 5kW (22 Amps) would be a good estimate without actually putting a meter across the mains and dynamically measuring it.  That's going to be 5kW Peak, so the actual current that you draw at any given moment will be less than that.