Protecting cables in the garden...recommendations?

[emadmoussa]

I'm using a 2-way extension reel to power up both the mount and the USB hub. It seems a bit exposed to moisture and I'm thinking if left out for a long time it might become dangerous. Do you guys use some protection for such item?

[Gilez]

First of all, make sure you are using an RCD (power breaker etc) on you extension lead.

In terms of the cable, there won't be much you can do if you are always reeling it in and out. Just check it for any obvious breaks or damage. If it is a more permanent feature you should consider replacing with a suitable permanent wired alternative, getting an electrician in to do it.

As for the actual outlet end, you could try to put in inside a suitable plastic box ( one of those clear lidded stackable storage boxes for example) would help keep any dew at bay.

[Macavity]

On my mind too at the moment. But I never leave any MAINS cables / equipment around in the wet - The mere damp. "Signal" cables, short term, I am less bothered. Astro Setups seem to survive DEW / FROST with impunity?

As mentioned above, an RCD adapter - At the mains socket, inline in the cable etc., reassures me...

Currently thinking about IP65 (rating) sockets (enclosures) etc. Cable Ducting, for an observatory etc.

[emadmoussa]

Mmm...seems about right.

I'm thinking the mount (NEQ6) might require protection, or not? If I cover it to protect from moisture...

[earth titan]

The RCD is vital as already discussed.

I would make up a dedicated lead, with IP rated sockets in. IP is a rating for ingress protection - off the top of my head, IP54 is what you need.

Typed by me on my fone, using fumms... Excuse eny speling errurs.

[Bizibilder]

I now run mains to my observatory and all the leads and wiring are designed for and sold as camping/caravaning equipment. It is protected by an RCD at the house. The sockets and other gear in the observatory is damp proof and stays completely dry in use. My 13.8v power supply box lives under an upturned plastic box - just in case any condensstion drips occur but I have not had that problem yet. At the end of a session the extension is wound up and lives in the observatory.

In use the cable is run from the observatory roof via a couple of plastic poles to a window in the house. Thus it is kept at least 6' in the air throughout its length and cannot present a trip hazard. It also keeps the cable out of any damp on the ground, although dew does form along the cable - this is wiped off as I coil the cable up when putting it away. A couple of pics:

The poles are plastic waste pipes, they sit in a couple of rotary washing line "spikes" and have fishing pole clips on top to hold the wire. Total cost - less than £10

[Macavity]

I now run mains to my observatory and all the leads and wiring are designed for and sold as camping/caravaning equipment. It is protected by an RCD at the house.

I do something rather similar? Mains goes via RCD, (at the moment via) "fanlight", 16A "Caravan Cable", along concrete path, to pukka "Blue" socket in side of obsy! Mostly to charge a Deep Cycle battery. If I need extra current and there is no rain, I can run lighting and a fan heater! But quite nice to isolate the obsy from Mains... *noise* (general noise!) during imaging attempts.

Aside: Am working on 90' SIGNAL cable run (coax, USB via cat5 etc.) for remote Video Astronomy stuff? Have "IP65" boxes at either end. If that seems to work OK I might look into "armoured cable" for mains... eventually.

[Pig]

Hiya,

IP65 is what you need for non settling water or water sprayed from a nozel at a given pressure.

The first digit is for dust / minerals (6), the second digit is for water / liquid (5).

To be totally safe and to protect your expensive equipment you will need IP68 (submersion, the product should state at what depth and for how long )

[Kropster]

I run my cable out through the cat flap, under rubber safety mat across path, then into electrical flexible conduit buried in ground..to shed where PC is.

Mount is powered from portable battery pack (cheapo Argos).

[Stevie816]

For what it's worth.

I,ve used and extension lead across the grass for years. with an RCD fitted.

However..... (there's always a however). I have one with a white cable so I can see it on the grass. and I have plenty of slack in it so that even if I do trip on it `i don't rip anything out.

`On the 12 volt side to the scope I have fitted a cheap push fit plug and socket (90p from B&Q) which will pull apart easily if i snag it and not pull the wire from the transformer or scope.

This little mod has saved the day quite a few times.

As far as waterproofing, i'm not going to worry unless underwater astronomy catches on. What could possibly go wrong ?

Steve

[Pig]

A spike / surge could very easily go wrong

A transistor will go pop a lot faster than an RCD will trip out and they are in many circuits, an RCD might stop you getting a shock but it wont stop you blowing sensitive components into oblivion.

[upahill]

I agree that caravan cabling is the way to go. Maybe get an outside socket box which is IP65 rated and fit a caravan socket to it.

That way you can just run a big orange cable out and plug it in to the socket box.

[The Sailor]

I have my cables, CAT5/Power running overhead, RCD at the start and the cables run through loops along a heavy wire to the observatory. The loops are placed every two foot or so and the cables loose to prevent any tension, this system has been there about three years, will soon be removed as the obsevatory is now redundant but has served well.

Jim

[laser_jock99]

I buried my mains cable in plastic conduit about a foot down.

[earth titan]

I buried my mains cable in plastic conduit about a foot down.

Long as you remember where they are :-)

Typed by me on my fone, using fumms... Excuse eny speling errurs.

[astrofox]

As upahill said. Use a caravan cable if you must leave it out. They and the IEC blue plugs are designed for outdoor use. After all its what you do at a caravan site.

[bomberbaz]

Buy some proper armoured cable, bit more expensive but give the best protection and when your talking electric, no half measures really. Ideally it should be 18" deep. Take a picture of your trench or make a sketch.

more info here http://www.diynot.com/forums/viewtopic.php?t=101500

[J_M_Franklin]

Buy some proper armoured cable, bit more expensive but give the best protection and when your talking electric, no half measures really. Ideally it should be 18" deep. Take a picture of your trench or make a sketch.

more info here http://www.diynot.co...ic.php?t=101500

Whilst the advise given there is correct for cables buried in the garden, you also need to take into account things such as volt drop (this impacts the size of the cable used for the given length and loading) (Not likely much of an issue for a simple observatory) and you also need to know how to terminate SWA. For the DIY'er I would suggest using NYY-J cable would be a better choice, although cost is a factor, 4mm HYY-J comes in at £2.22 per meter whereas 4mm SWA is £1.63. However there is ease of termination and the fact that HYY-J cable is designed for use in extreme environments, does not rot in moist/wet environs and is rated down to about -40°C. SWA can be used in moist environs and can be used down to about -10°C but is degrades with age, moisture can leach into the sheath if there is the slightest imperfection and this damages the armouring.

As upahill said. Use a caravan cable if you must leave it out. They and the IEC blue plugs are designed for outdoor use. After all its what you do at a caravan site.

If you use commando sockets (the IEC plugs and sockets) then you MUST consider overload protection. RCD's only provide Earth Fault protection, you must ensure any circuit also has overload protection, but especially when it feeds any equipment outside. Relying on the circuit protection of the circuit you feed it from is dangerous. The supply you need in the Observatory, unless you have heaters, does not need to exceed 10A (2300W) and in real terms will not exceed 5A. The scope uses a couple of A and the PC the same.

Circuits should be designed correctly for any service, but especially if they supply circuits outside.

[Gilez]

Remember that any fixed wiring falls under special locations when outside in the wiring regs and is notifiable in accordance with the Building Regulations.

[earth titan]

Remember that any fixed wiring falls under special locations when outside in the wiring regs and is notifiable in accordance with the Building Regulations.

Unless you plug it in to an RCD on the wall in the house, as I understand it.

[laser_jock99]

Remember that any fixed wiring falls under special locations when outside in the wiring regs and is notifiable in accordance with the Building Regulations.

Good advice- although I did the work myself I had the job checked & approved by an electrician.

[emadmoussa]

I'm not planning on keeping a permanent set-up in the garden. What I'm doing at the moment is an extension lead plugged into an RCD inside the house, then runs 2 meters into the garden. On one of tripod legs I have a USB hub and underneath it there's a plastic box for the dangling plugs.

[Macavity]

Have resolved to run signal cables "overhead" - Just bought some "eye-bolts" etc.

Will leave the MAINS power connected "Caravan [Gangnam?] Style" for the moment.

Neglected to think about routing low-voltage stuff above ground. Catenary and all that.

OK, plastic coated steel, "washing line"! For that idea / reminder, I am indebted tho!