USB and other leads required for a pier

[Terrierist]

Folks,

Apologies if this is in the incorrect place.

I'm about to start building a pier, it will be some 15 metres away from the house.

Considering this distance, what will I need to run the various cables from the house to the mount? I have read that after 5 metres, the USB cables need a relay/boost, is this the same for guide cables etc?

Thank you for your help.

 

Kev

[RayD]

16 minutes ago, Terrierist said:

Folks,

Apologies if this is in the incorrect place.

I'm about to start building a pier, it will be some 15 metres away from the house.

Considering this distance, what will I need to run the various cables from the house to the mount? I have read that after 5 metres, the USB cables need a relay/boost, is this the same for guide cables etc?

Thank you for your help.

 

Kev

Yes USB starts to degrade after 5m, so at 15m you are well over.  You can use USB over LAN extenders such as these which work very well up to 50m or so.

[Terrierist]

15 minutes ago, RayD said:

Yes USB starts to degrade after 5m, so at 15m you are well over.  You can use USB over LAN extenders such as these which work very well up to 50m or so.

Thanks for the reply, Ray.

Am I correct in thinking that the Cat 5/6 cable comes out of your ethernet connection on your PC/Laptop and converts at the box to USB?

How does the imaging/control software see this and recognise the USB connections through the ethernet connection?

Fascinating stuff!

 

Kev

[Dr_Ju_ju]

If you already have power at the pier, why not run a network cable to the mount, then site an adjacent computer & run all cabling to it. It then runs the mount, imaging etc. and you can then remotely control the computer from inside your house...

Its what I do, so do many others....  You could try wifi control, but I find its too slow especially when I also download all images to remote storage.

[RayD]

16 minutes ago, Terrierist said:

Thanks for the reply, Ray.

Am I correct in thinking that the Cat 5/6 cable comes out of your ethernet connection on your PC/Laptop and converts at the box to USB?

How does the imaging/control software see this and recognise the USB connections through the ethernet connection?

Fascinating stuff!

 

Kev

That's correct.  You plug the sender in to a USB on your indoors PC, that converts it and sends it off down the Cat5/6 cable, and the receiver at the other end converts it back. it basically works exactly the same as having a local PC but sends the signal using a different protocol giving you more distance.

As @Dr_Ju_ju notes, if you can site your PC at the pier and then connect to that via LAN, wifi or similar, then that is probably a better route, and is how my observatory runs, but the USB extenders do work if this isn't an option.

[Terrierist]

10 minutes ago, Dr_Ju_ju said:

If you already have power at the pier, why not run a network cable to the mount, then site an adjacent computer & run all cabling to it. It then runs the mount, imaging etc. and you can then remotely control the computer from inside your house...

Its what I do, so do many others....  You could try wifi control, but I find its too slow especially when I also download all images to remote storage.

Hi, Julian.

This is my first attempt at a pier/mount and I would love to be able to control all from a single computer inside the house, is this possible or is it better to have two computers? How do you control the slave computer from the house, which software?

Sorry for all the questions!

 

Kev

[upahill]

I use Tight VNC to access a 12v mini pc stuck on the tripod / pier. That way I can access it from indoors, and if i need to do any adjustments on the mount and see the screen I can VNC in from an iPad wirelessly.

 

[Anthonyexmouth]

i use a 20m active/repeater usb cable. £30 on amazon and then a hub outside that i plug my cameras and mount into . cheap, single cable and works. 

[Terrierist]

4 minutes ago, Anthonyexmouth said:

i use a 20m active/repeater usb cable. £30 on amazon and then a hub outside that i plug my cameras and mount into . cheap, single cable and works. 

Thanks for this, do you have 12v lines outside also, to power camera, mount etc?

[Anthonyexmouth]

1 minute ago, Terrierist said:

Thanks for this, do you have 12v lines outside also, to power camera, mount etc?

no, 240v, i've got outdoor power sockets dotted around the garden. got a power strip taped to the tripod leg that then plugs in. but any extension lead would do. 

[spillage]

I have used an old pc at the mount with a power supply and cat5. Depending on your set up you could also buy a second wifi router as as a wifi extender. I just found cat5 more reliable.

[Terrierist]

6 minutes ago, Anthonyexmouth said:

no, 240v, i've got outdoor power sockets dotted around the garden. got a power strip taped to the tripod leg that then plugs in. but any extension lead would do. 

Ok, that's another thing i'm trying to get away from, I've got RCD protected supplies but still nervous about 240V outside!

[Anthonyexmouth]

1 minute ago, Terrierist said:

Ok, that's another thing i'm trying to get away from, I've got RCD protected supplies but still nervous about 240V outside!

dont be nervous, i use 240v outdoors for work all the time, up on roofs in the wet, grinders and skill saws. RCD extension leads are safe, at worst its a little bit of dew you'll be dealing with. if its raining you wont be imaging. 

[Dr_Ju_ju]

Using armoured mains cable that is properly terminated and supplied via an RCD, then there's no issues running mains to your pier\mount.

Have a look through this thread, which shows what I & others have done..

https://stargazerslounge.com/topic/317577-open-air-pier-mount/?tab=comments#comment-3473580

 

[mallorcasaint]

I have no mains going to my pier outside in the garden. It is not needed. All you need are a couple of Bench supplies (13.8v) in your house/warm room and run 12v to the pier on multiple lines. I then have converters at the pier that drop one of the incoming 12vdc lines to 5v dc for my Quark etc. I also have 4 way cigarette connectors at the pier for tghe mount and other devices. All the cables are run underground in a trench and a 2 inch flexible pipe.

[Terrierist]

9 hours ago, mallorcasaint said:

I have no mains going to my pier outside in the garden. It is not needed. All you need are a couple of Bench supplies (13.8v) in your house/warm room and run 12v to the pier on multiple lines. I then have converters at the pier that drop one of the incoming 12vdc lines to 5v dc for my Quark etc. I also have 4 way cigarette connectors at the pier for tghe mount and other devices. All the cables are run underground in a trench and a 2 inch flexible pipe.

Thanks for this, I am leaning more and more towards 12V,  I understand what others say about RCD and armoured cable but I am still nervous about it.

[Anthonyexmouth]

Outdoor electrics are nothing to be nervous about. water + electricity does not = danger. no one thinks twice about dish washers, washing machines, electric showers and most common of all, electric kettles. 

[PaulR1]

42 minutes ago, Anthonyexmouth said:

Outdoor electrics are nothing to be nervous about. water + electricity does not = danger. no one thinks twice about dish washers, washing machines, electric showers and most common of all, electric kettles. 

Agreed , I have 240 outside running to my obsy ,when Its not in use I just unplug it. Dont even worry about it

I also use the startech USB over Cat 5 boxes which work a treat. However these are USB 2.0 which run all my current equipment fine.

Im not sure about some Astro cameras though which I think are USB 3.0. 

(gonna start a thread)

[RayD]

1 hour ago, Anthonyexmouth said:

Outdoor electrics are nothing to be nervous about. water + electricity does not = danger. no one thinks twice about dish washers, washing machines, electric showers and most common of all, electric kettles. 

Hmmmmm I'm not so sure.  Water + electricity does indeed = danger (or more accurately a hazard), but when combined in a well designed and well protected circuit the resultant risk is mitigated by implementing measures such as segregation and enclosing key components in IP65 enclosures etc.  Go and fill a bath, sit in it, plug your toaster in and chuck it in there and see what happens (don't do this really, but you get my point).  The items you described are specifically designed to work in close proximity with water (you could have included swimming pools cleaned by using 400v 3 phase pumps), but an extension lead run outside in a garden isn't necessarily designed for this purpose.  

Even H&SE guidance says that work tools for any site should be 110v centre tapped (maximum 55v earth potential) as 230v poses significantly higher risk.  This is why no construction site satisfying CDM 2015 (so that now also means a sole trader working on someone's house) will allow you to use 230v power tools on site; and rightly so.  Personally I'm gobsmacked that anyone would even want to given the increased risk.

As someone who spent 5 days in hospital with all manner of things plugged in to me beeping and testing following a very serious electric shock at work, and still bearing the burn scars from it 20 years later, I can tell you that (mains) electricity is dangerous whether mixed with water or not (the water just increases the risk of shock), so just urge people to make sure any supply is well thought out and adequately protected, both electrically and mechanically. 

My view, and after all we are all just relaying our views, isn't saying 230v run outside is not suitable in our hobby or any other application, of course it is, but just do it right.

PS I work in the lift industry and last night received the very sad news that a 24 year old lad who got an electric shock whilst working on a lift 10 days ago, and had been in hospital since, had just died.  230v shock, no water.

[hughgilhespie]

Hi,

If you decide to go with a low voltage supply to your pier you will need to use cables that are hefty enough to carry the current you need without too big a voltage drop. If you plan for the future when you may want to run a laptop via a 12 volt adaptor as well as the mount and everything else you should think about supplying about 10 amps as a minimum and probably have the indoor power supply rated for twice that. Using 14 awg wires you will still drop nearly a volt at 10 amps over 30 meters (there and back). So, you would want to go for at least a 13.6 volt PSU to give you 12.6 volts at the pier. A 14 volt PSU would probably be better.

There is a very good cable manufacturer / supplier I have used, Batt Cables, and they have branches in most UK areas. They do very good marine grade two core cable and there is a voltage drop calculator on their website.

HTH

Regards, Hugh

[RayD]

You can get 2 core thin wall, used for marine applications, from 12v planet here.

[Gina]

I got 16.5A similar from Amazon which I use from warm room to pier - total length of about 4m.  One core for mount and the other for other kit.  I run a much heavier ground wire (about 3mm core) which is connected to a 4ft in the ground copper earth rod (clear of the observatory so that it gets wet when it rains) to pier-head and then to warm room.  The latter has a mains supply with RCD protection, plugged in to the house ring main, avoiding the need to comply with regulations that apply if connected directly to the fusebox.  I am, however, very cautious with mains supplies and the pair of sockets in the scope room are IP65.  (OK so the scope room is not supposed to get wet but dew in winter can be very heavy with everything dripping.)  Lighting in the scope room is LED strip supplied from the warm room.  Mains and damp are kept well apart.

[Jkulin]

I too would not run 240v out into the garden, I had nightmares of my wife finding me lifeless in the garden following a night imaging and then in haste run to see me and electrocute herself as well.

I now run into the lean to shed proper waterproof 240v sockets which in turn feed two of these Nevada 25-30A PSU 13.8v: -

https://www.nevadaradio.co.uk/amateur-radio/amateur-radio-power-supplies/nevada-psw-30

I then run to lengths of 20+ Meters of 2.5mm cabling out to my pier that feed via waterproof connectors my pier, Pegasus UPB and laptop, I don't take risks when it can be avoided.

[Gina]

If you use a proper RCD it will trip before you are electrocuted.  Plus if you do the electrics properly there will be nothing to even give you a tickle!  OK so I have a degree in Electrical Engineering and I know what I'm doing.  Have worked with electricity in my career (including very high voltages) and in DIY projects including house re-wiring.

[RayD]

Spot on.  Doing it properly is the key thing, which includes adequately mechanically protecting the cables to reduce the likelihood of damage (suitable location is a form of mechanical protection).