Cabling for outside pier

[mallorcasaint]

Just wondered if anyone has done this. I have a brick shed I use as an observatory and until now I have run cables out to my tripod across the grass. I am installing a pier in the garden and want to control the mount from inside the obsy shed ( I have all the tech for that sorted out). My question is, what's the best way to get power/data cables to the mount. I'm thinking of digging a trench and laying flexible plastic pipe to carry the cables. I need a couple of 13amp sockets by the pier for some of my equipment so should I install a couple of outdoor, waterproof sockets or just run an extension lead through the trench? I'll run a 12 volt line through the trench as well as a USB over Ethernet cable. Any ideas welcome.

[Uplooker]

To be honest you really, really need to have the cables at the house end connected to an Residual Current Device (RCD). On the run to the Obs you really, really need to use armoured cable, preferably within a conduit this also makes pulling additional cables through a LOT easier, that is at least 18 inches below the surface, marked as power cables and covered with sand. Within the obs you really need to use IP65  (Ingress protection/ International Protection).

Dont quote me on the IP protection as I am not an 18th edition electrician!

[RayD]

2 minutes ago, Uplooker said:

To be honest you really, really need to have the cables at the house end connected to an Residual Current Device (RCD). On the run to the Obs you really, really need to use armoured cable, preferably within a conduit this also makes pulling additional cables through a LOT easier, that is at least 18 inches below the surface, marked as power cables and covered with sand. Within the obs you really need to use IP65  (Ingress protection/ International Protection).

Dont quote me on the IP protection as I am not an 18th edition electrician!

Nor is anyone until 2018 

Good advice though, or best advice really is get a sparks to do it.  To be legal it needs to be registered with Part P.

[mallorcasaint]

Thanks guys. The Obsy building is already legally connected to the house and has it's own consumer unit. I think I'll be running a mains spur from an RCD in the shed and run the cables through armoured tube.

[MarkyD]

If the power to the shed is already protected by a 30mA RCD you don't need one in the shed.  It called discrimination.

[mallorcasaint]

5 hours ago, MarkyD said:

If the power to the shed is already protected by a 30mA RCD you don't need one in the shed.  It called discrimination.

Yes it has MarkyD. Thanks,

[mallorcasaint]

Update: I have now designed my cabling so that mains is not required at the mount. I am running two separate 12v lines from two bench supplies in the obsy building amd I'm using 2 12v to 5v dc regulator/convertors for supplying a couple of devices. I'm also running Cat5 cable for the USB over ethernet. All the cabling is in a corrugated plastic conduit buried in a trench. The connections at the mount will be terminated in an IP6 box mounted on the pier. So far so good!

[RayD]

29 minutes ago, mallorcasaint said:

Update: I have now designed my cabling so that mains is not required at the mount. I am running two separate 12v lines from two bench supplies in the obsy building amd I'm using 2 12v to 5v dc regulator/convertors for supplying a couple of devices. I'm also running Cat5 cable for the USB over ethernet. All the cabling is in a corrugated plastic conduit buried in a trench. The connections at the mount will be terminated in an IP6 box mounted on the pier. So far so good!

Great idea, much safer and should have no impact on performance at all 

[Adam J]

My problem with running armored cable is that it seems impossible to get it in short lengths and its so so so expensive. I need about 4 meters to get to my obsy and you cant buy less than 20 meters of the stuff locally.

[Adam J]

22 hours ago, mallorcasaint said:

Update: I have now designed my cabling so that mains is not required at the mount. I am running two separate 12v lines from two bench supplies in the obsy building amd I'm using 2 12v to 5v dc regulator/convertors for supplying a couple of devices. I'm also running Cat5 cable for the USB over ethernet. All the cabling is in a corrugated plastic conduit buried in a trench. The connections at the mount will be terminated in an IP6 box mounted on the pier. So far so good!

Silly question but is USB over Ethernet literally converting the USB into TCP/IP protocol and back or is it just sending USB serial data down an RJ45 cable (in which case it would be more accurate to call it USB over cat5/6)?

If so can you then send it over a network power adapter?

 

[mallorcasaint]

52 minutes ago, Adam J said:

Silly question but is USB over Ethernet literally converting the USB into TCP/IP protocol and back or is it just sending USB serial data down an RJ45 cable (in which case it would be more accurate to call it USB over cat5/6)?

If so can you then send it over a network power adapter?

 

Yes, you are quite right. It is actually USB over Cat5/6. I use the Startech gear and it works beautifully. No need for dodgy active USB cables and just one 10mtr Cat 6 cable for all the data.

http://www.officenerd.co.uk/info/startechcom-4-port-usb-20-over-cat5-or-cat6-extend-1220795?gclid=Cj0KEQjwldzHBRCfg_aImKrf7N4BEiQABJTPKJ_VI5X7KgiGkKbhEt9rUuu62esH2LfTyVD85tDrgdoaAh9M8P8HAQ

[MarkyD]

12 hours ago, Adam J said:

My problem with running armored cable is that it seems impossible to get it in short lengths and its so so so expensive. I need about 4 meters to get to my obsy and you cant buy less than 20 meters of the stuff locally.

CEF sell it by the meter.

http://www.cef.co.uk/catalogue/categories/cables-and-accessories-swa-xlpe-pvc-armoured-cables

[mallorcasaint]

Pier is in with all the cabling in the trench in a 40mm reinforced flexible pipe. No mains at the pier only 12 and 5 volts.