# Outdoor power points

#### Julian De Jong

##### Apprentice elf
Hi everyone
I’m looking at getting a few outdoor power points installed for my display this year as I currently only have one outside which is used for my water tank pump. I am trying to get an idea of how many I realistically need for my display.
My display will be using around 10-11 psu’s powering around 7000 pixels of a mix of strip and nodes. All pixels are 12v running off of 350w psu’s.
From reading other posts my understanding is that depending on the efficiency of the psu they will typically draw upwards of around 1.6 amps on the 240v side, assuming they are running at full power. Although I won’t be running the lights at full brightness I am planning my power requirements based on full brightness. My other understanding is that each power point can typically handle a maximum of 10amps, with the understanding that the circuit that the power point is on can only handle 16amps in total across all power points in use across that circuit.
I know I am probably trying to cover off on allot of different factors here but with all of the above in mind, I was hoping to get some advice on how many power points I would realistically need to power my display?
From my calculations, assuming a draw of 1.6amps I would need two power points, with each power point running off different circuits. However that doesn’t seem like enough to me and I am thinking I have misunderstood something along the way.
Thanks everyone.

#### ezellner

##### Full time elf
I run about 8,000 5 Volt pixels from one 120 Volt 20 Amp circuit with no issues so your calculations seem about right to me.

#### bpratt

##### Full time elf
Generous elf
It's not so much about the number of power points, but the number of circuits you should be looking at having.

You say 1.6 amps per power supply, then 10 of them would be 16 amps.

You will get surge currrent draw when they all get turned on in one hit, which might, but not necessarily will trip your usual 20 amp circuit breaker.

For sanity sake, I think I would be running two separate circuits for your lights display, and if you're like the rest of us 'nuts' in here, next year your display will be bigger.

How far from your house are you running your display ? If it is some distance like I am (100m from the road), then speak to your sparky about using a thicker gauge cable than the usual 2.5mm, i.e. 4mm, as when you're running a full current draw on the circuit, your mains voltage can drop.

Remember, whatever is said in here with mains voltages, you should always refer to your local sparky for full clarification.

#### scamper

##### Dedicated elf
The above is all correct. I have 16000 pixels, and will be adding more this year, so allow for more as it will happen
In reality, they draw very little while running, but the inrush at startup can trip out your breakers if it gets close to the limit, I found this the hard way when I had half my display running on the same circuit as my fridge. When the fridge was on, and I turned on my display it would trip. As you could imagine it took a while to discover, as it was intermittent, ie only when the fridge was running.
The more important thing in my mind, is where the points are located. If you are getting them installed specifically for xmas lights. Think about where the controllers are going to be and get power as close as possible to that and spend a few more bucks if necessary to do so. Also, if you are getting a sparky there to do that, then maybe add a couple extra, just in case.
one last thing on the inrush current, that is really only going to happen if you have one master switch that turns it all on at once. If it is left running on idle or switched on in stages, then it won't make much of a difference.

#### Mark_M

##### Annoying Elf
Generous elf
If you're planning on getting a sparky to install power outlets I'd ask to have a separate circuit installed with an RCD and standard breakers.
And if you've got more money to spend I would highly recommend decent outdoor outlets. I got a really beefy PDL-56 series outlets.

Inrush current is a very good point. Some devices known as 'soft starters' limit the inrush current, otherwise a series of timers to start supplies sequentially.

#### djgra79

##### My name is Graham & I love flashing lights!
Generous elf
Staggered power on from different circuits will be a safe option for the future. My show runs from 2x power outlets but on 2 seperate house circuits. The outdoor point I got installed a couple of years ago has 2x AC timers on it a couple of mins apart to switch on so the point and therefore circuit is not overloaded at the switch on spike.

##### New elf
Hi All,
In a similar vein to Julian's post, I have just had some new points installed for this year for my expanded display and have been looking at the current draw from the PSU's. I am using the Meanwell LRS-350-12 and the spec sheet details an AC current of 3.4A at 240V (and a 60A inrush current)

My understanding is that the 350W PSU's generally draw about 1.6A so I am really confused by the 3.4A draw. Am I missing something with the Meanwell spec sheet?

Any help is appreciated.

#### SAALTFAM

##### Sparky with Blinky Lights ;-)
Generous elf
And yes they can draw 60A in inrush if it is fully loaded when turned on.
It may be for about 5-30ms and depending on what the circuit breaker is it should hold in unless that circuit is almost fully loaded.
Get a RCBO type (plain circuit breaker with a RCD built in)
Your sparky should do the voltage drop and current rating to determine the correct size cable, and always get a licensed electrician to do the 230V stuff.

#### Julian De Jong

##### Apprentice elf
Thanks for your replies everyone good to hear I was on the right track!
I will be using different circuits but I hadn’t even considered in rush so that is good to know. The way my display is set up I would probably be staggering powering everything up so I don’t think that will be a problem.
At this point I think will have to only install the minimum number of power points needed for my display this year as I’ve already spent more than I anticipated and I still have to get everything for my mega tree. I’m sure I will be expanding, I haven’t even set it up this years yet and I am already planning for next year, so will need more points down the track but my budget won’t allow it. I know it will probably cost more in the long run getting a sparky to come twice unfortunately.
On the question from elad, I’ve had a look at my psu’s and I noticed the same ac current of around 3.4. Saaltfam, when you mention overload current does this affect how I need to plan out my power points?