Site vault power

[RF Lighting]

Hi all. I'm looking to buy a new site vault. This is the sort of thing if you're not familiar with them:
They're used to store tools, materials, drawings and anything else which may go walkies on a construction site.

I'd really like to wire it up for power.

The standard power on building sites is 110V CTE, so I am going to mount a 16A 110V CEEform inlet on the rear of the vault to provide power to the inside.

What I'd like is an inlet which I can somehow secure the extension cable into to stop the lead being unplugged or pinched when it's left unattended.

I'm thinking I'd like a couple of 110V 16A CEEform outlets on the inside and maybe one or two on the back of the vault.

I'd also like a couple of 230V 13A sockets to allow standard drill battery chargers to be plugged in, and a couple of USB sockets for charging my phone and iPad.

My initial thought was a large adaptable box mounted inside the vault with some panel mount 110V panel outlets fed directly from the inlet.

For the 230V outlets I was thinking about sitting a 1.5kVa yellow site transformer in the bottom of the vault and wiring it up in reverse. I'd supply it directly from the inlet, and then back into the adaptable box with maybe a twin socket with USB outlets on the front of the box. I guess this would require some sort of over current protection on the 230V side?

Any ideas or suggestions would be most welcome.

 

[Adam_151]

Is 240v necessary?, I would have thought a lot of switched mode tool chargers these days would work over a range down as low as 110v... if only so that they can sell the same charger design just a different plugtop (shut it winston!) in different countries

 

[RF Lighting]

I tried a couple of my 230V chargers on 110V and they don't work.

 

[Adam_151]

In that case then if you have both the space for the transformer and the extra weight is not a problem (how is this getting from the van to the site?)

I would be tempted to put the over current protection on the primary (110v) side and not bother with anything on the 240v secondary. If there are multiple pieces of kit being used, you'd probably want to tie one side of the transformer to earth rather than running an IT system and then stick a 30mA RCD on it

 

[Spark123]

You can buy 110v-240v transformers, the one I have is blue. The output of it is electrically separate, like a shaver socket.
As for the extension getting robbed, two options I can see are to have the inlet inside or put a staple (from a hasp and staple) on the outside and put a padlock on it, run the cable through the padlock so it isn't easy to pinch.
http://www.screwfix.com/p/carroll-m...tracking url&gclid=CKOz273R4c4CFaQW0wodriQO_w

 

[Iggifer]

If you go with a site transformer in reverse, something like this would be easier to work with - you could almost bolt it to the side inside to keep it out of the way (only 600Va on that one though)

 

[RF Lighting]

I'm thinking of maybe having a 110V outlet and 230V inlet on the bottom of the adaptable box so the tranny can be removed for transporting the box.

I can't decide whether to leave this as an isolated IT supply or to earth one side down. I think the risk is minimal as its a controlled environment and would be unlikely that class 1 equipment would be supplied from it.

I've seen those blue step up trannies but they all look to be 3kVa which may be a bit too bulky and heavy.

The hasp and padlock idea is perfect! I'm never going to prevent someone who's determined to nick it but it should stop someone borrowing it and 'forgetting' to return it...

 

[333rocky333]

Do interlocked inlets allow a padlock also in the On position to prevent removal of plug

Years ago inside site fleurescent lights there was a small 110 to 240 transformer only about the size of a choke not sure if there still allowed on site or of any use to adapt to run a small load like a charger.

 

[Iggifer]

Do interlocked inlets allow a padlock also in the On position to prevent removal of plug

Even if they don't, you could soon fix that with an 8mm drill bit. Not that interlocks are fool proof, seem to get weaker over time until they just don't fully lock anymore.

 

[RF Lighting]

I've now got my site vault and have a proposed design for the power.

I've decided to keep things simpler than my original design.

I'm going to install an adaptable box fitted with a 16A 110V BSEN60309 and a 13A BS 1363 socket both wired direct to the 55-0-55V supply.

This will allow me to use standard 110V equipment and SMPSs to charge my phone / laptop.

I'm thinking if I fit a BSEN60309 inlet on the vault it's likely to get smashed off, so I was thinking of using something like a flush mounted neutrik powercon inlet instead.

Would a non BSEN60309 connector be suitable / compliant to use on a construction site supply or is there a better solution I'm missing for this purpose?

 

[SUNRAY]

I've now got my site vault and have a proposed design for the power.

I've decided to keep things simpler than my original design.

I'm going to install an adaptable box fitted with a 16A 110V BSEN60309 and a 13A BS 1363 socket both wired direct to the 55-0-55V supply.

This will allow me to use standard 110V equipment and SMPSs to charge my phone / laptop.

I'm thinking if I fit a BSEN60309 inlet on the vault it's likely to get smashed off, so I was thinking of using something like a flush mounted neutrik powercon inlet instead.

Would a non BSEN60309 connector be suitable / compliant to use on a construction site supply or is there a better solution I'm missing for this purpose?

What we did with ours was to mount a yellow inlet directly on the 'blue step up tranny' which already had a DSSO fitted, our safe was a tall version with a shelf high up along the back. We then cut a hole in the side of the safe for the inlet to poke out and and some brackets on the inside of the lid which held the tranny in place. During transit the tranny was turned through 90' so the inlet was inside and the hole obscured by the blank side of the tranny.
If it was needed anywhere else it just lifted out leaving a 4" hole.

 

[Robin0577]

I've now got my site vault and have a proposed design for the power.

I'm thinking if I fit a BSEN60309 inlet on the vault it's likely to get smashed off, so I was thinking of using something like a flush mounted neutrik powercon inlet instead.

Would a non BSEN60309 connector be suitable / compliant to use on a construction site supply or is there a better solution I'm missing for this purpose?

You can get recessed versions of the blue 60309s for use on caravans etc, not sure if they do them in yellow though. That said, the actual plug components are probably interchangeable with others from the same manufacturer.

http://www.mennekes.co.uk/index.php...ommerce_pi1[mapid]=000000040000546200010023:1

 

[SUNRAY]

I've now got my site vault and have a proposed design for the power.

I've decided to keep things simpler than my original design.

I'm going to install an adaptable box fitted with a 16A 110V BSEN60309 and a 13A BS 1363 socket both wired direct to the 55-0-55V supply.

This will allow me to use standard 110V equipment and SMPSs to charge my phone / laptop.

I'm thinking if I fit a BSEN60309 inlet on the vault it's likely to get smashed off, so I was thinking of using something like a flush mounted neutrik powercon inlet instead.

Would a non BSEN60309 connector be suitable / compliant to use on a construction site supply or is there a better solution I'm missing for this purpose?

Basically anything that is compliant is suitable for site work BUT site owners make up their own rules. For example 230V can be used legitimately but most sites will not allow it (We once had to make special arrangements to come on site after hours to power and test a projector hoist with a 230V transformer but even though the transformer was right beside the hoist they insisted we had to add; DP mcb/rcd external to the transformer which already included DP mcb and rcd DSSO and blue, 2.5mm² cable between transformer and load).
I really do think you are trying to over engineer this, basically everything you want already exists on a 'blue' transformer. Our solution of cutting a hole for the plug to stick through worked extremely well, it was like it for at least 5 years without a single down side (other than a hole if the transformer was not in position). If you don't want to make such a big hole, how about an inlet and an outlet 'back to back', just to get the power inside. The DSSO with USB mounted on the transformer completes the simple set up and is portable for when it's needed elsewhere.
Your concern about damage can be addressed with a bit of steel work to protect it.

If you do reconfigure a yellow (230v to 110v) transformer, make sure you disconnect the earth from the centre tap of the 110 side. If you don't there will be some high currents flowing. Additionally, in the event of a phase wire failing elsewhere you will find your transformer supplying 55 of the 110v to other parts of the site.

What size of transformer do you really want? For example a 200VA panel transformer in your adaptable box will be a lot lighter than a site transformer if thats all you require. I used a 50VA in a 47mm back box on the back of a single 13A metal clad socket for soldering iron etc.

Oh and some sites do not allow tool safes to be powered.