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Bench Unit ("In the field")


Guest Kheldar

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Guest Kheldar

So I'm a bit thick when it comes to avoiding blowing myself up, so I hope someone can assist smile.gif

I image either in my back garden (no obsy) or in a field (star party) so I'm never away from a mains supply. RCDs are always in chain.

Now I have a million cables, and I'm trying to address this by looking at a mount hub pro. I can sling this up on the mount and run short lengths of cables to power/usb all my devices smile.gif

Now the blowing myself up bit ... given that I use mains power (not leisure batteries) : the sensible way to power the hub would appear to be a 13.8V 15A (maybe less to save some pennies ...) bench unit ... which I'm given to believe can result in bad things if used outside?

Can this be addressed? Any advice / suggestions welcome smile.gif

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Guest Kheldar

Cheers Mick, my only reservation is the bench units have warnings on almost every site I've seen that say they need to be ventilated (I assume some form of gases are produce in low quantities?) : I'm not sure how to address waterproof and ventilated though?

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Ventilation is most likely only required to help keep them cool. I am assuming of course that I am thinking of the right thing, IE a PSU which takes 240v and gives outputs of 0-30v? In which case there will be no gasses released although they can sometimes create a bit of a plasticy burning smell when they are new due to heating of the wires on the windings. This can be a bit of a headache maker in confined spaces, but should wear off. If you don't mean PSU's then pass, I don't actually know what you are asking, sorry. A PSU is basically just like a speed controller on the old scalextric sets, they smell a bit from time to time, but don't produce any gasses, it's just a bunch of wires and coils etc, no witch-craft going on in there ;)

You could if you really wanted, put one inside a plastic box, in the bottom of said box put 2 x holes, one with a fan on and the other open. Stand it on blocks to allow room for air to move and that would keep the air circulating. Or just pt vents in the side of the box by making small slits maybe? Or fit a couple of those air vent covers that you get on some doors to each side?

Vents You can get them much smaller, but this is the sort of thing I mean. Just position so that the Louvers are facing downwards. The heat of the unit would stop dew forming inside I would have thought so you're only trying to stop rain etc getting in, not that I imagine you being out in the rain for obvious reasons.

Edited by Perkil8r
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I'm referring to one of these. If it's the case that it's only heat that requires the ventilation then I'm leaning towards getting one and covering it above/below with tarpaulin ...

http://www.maplin.co...power-units-231

They only want cooling, as I say, it's just a bunch of wires, coils and iron rods etc, no witch-craft. It will quite possibly smell a bit, just like your old scalextric used to, but that's all. It probably will get quite warm.

Edited by Perkil8r
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Guest Kheldar

Hmm, fly in the ointment.

Bloody DSLR doesn't run off 12V, it's 7.6(ish) : which means some adaptor in-between the 12V (2.1mm jack) out from the hub and the camera :(

Single cable solution would of been so much nicer!

Edited by Kheldar
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There are some with multiple outputs. That might help? Or you could of course pop a variable pot in there to drop the voltage for that device. I can't think just now exactly which value hence the suggestion of a variable, that way you could test the voltage, adjust and test etc.... Maplins ;)

Edited by Perkil8r
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Guest Tweedledum

As above, generates heat but no noxious gases. If poss keep the PSU inside, run low voltage to the garden and then waterproof box & junction box. Your mains distribution board SHOULD (hateful word) have an RCD built in but to be sure plug the psu into one before the mains. As you are running low voltage you could consider running in trunking in the garden. If you want to use SWA I have some hanging up in the garage if you want it. You could always run 240v to the box with a variable low power ac adapter to provide 7.2 / 7.6v to replace lithium battery.

Range of waterproof and IP rated boxes here http://www.amazon.co..._sl_on1z7zvpq_b

Cheers

Edited by Tweedledum
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Guest Kheldar

Thanks for all the suggestions, going to have to sit down and have another long think about this I think :) Maybe the mount hub isn't the ultimate answer ....

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If you run the low voltage into the garden, the extra 1.8 volts will prevent the cable resistance dropping the voltage below 12v

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Guest Kheldar

Beginning to wonder if a 110Ah DIY leisure battery / usb box is a cheaper, better way to go than rely on AC power ... can still more or less consolidate wires, just means they will run to the foot of the mount rather than the trunk of it ...

Pricing it up it looks like I can build the box and buy a battery plus smart charger for less than the cost of the hub alone ...

I've no initial plans to use the dew heaters on the hub anyways!

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You could get a solar panel charger to charge it for a bit of eco-astrology lol. Small solar panel battery chargers are quite cheap really. Leave it out and keep it charged ready for use maybe??

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I put my mains PSU on a small slatted camping table with a tupperware box over the top - never had a problem with it. With a dew control system and a usb hub plus active usb extension cable I only need to run two wires to the mount from the house or caravan - power and data.

Camera cables and mount control are all wrapped neatly together in a spiral cable tidy :)

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I've got my mains supply on a plastic box with a lid. It is large enough to store cables and a mains extension. I prefer to use my Baz battery as I always end up tripping over the mains feed to the box.

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Yep i`ve a battery box, it fits two baz batterys inside cabled up, then i bought a four way cigar plug in adapter connected to the batterys, gives me about 60 amps total and enough plug sockets for mount and dew bands, i have to charge the batterys in the daytime with a 4amp charger which also fits inside the box,

box was bought from tesco`s for 6 pounds, it was dusty and on offer buy alittle wash and it was good as new.

forgot to add that i velcro the batterys to the bottom of the box to stop them moving around which works well,

Edited by red dwalf
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Guest Kheldar

I shall have to come have a mooch at that I think :)

Decided for SGL just to get the USB tidy (mount side hub) and rely on old gaffer tape to hold the PSUs up and stick with AC.

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I've got my mains supply on a plastic box with a lid. It is large enough to store cables and a mains extension. I prefer to use my Baz battery as I always end up tripping over the mains feed to the box.

Baz battery, I like that, I have a Baz battery too. :)

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