Extend/connect outdoor power line

Good day everyone,

slowly but surely our irrigation and electrical planning, as well as the planting of our outdoor area, are beginning.

Especially in the area of electricity, I am still unsure and would like to know how I should approach the installation of electricity outdoors.

I had my gardener lay two underground cables (3-core) at two different locations. These are connected to constant power.

The cables are currently lying in my still unplanted bed and are waiting for further installation.

The plan is to lay from the currently eastern area to the south area (19-meter-long hedge). Here we would like to have a few spots.

Therefore, the cable must be extended accordingly and also split over a length of 19 meters in order to connect different spots.

Since I have only dealt with electricity in a layman’s way so far (connecting lamps) and currently have no idea how to lay electricity outdoors, I am turning to you here.

I have read about systems ([brand name not mentioned here]) that have their own system with cables and thus also spots. But that is too expensive for me...

How do I lay or extend/split the power cable outdoors and connect it correctly and waterproof?

There are waterproof cable connectors and splitters. You can also find them with these keywords. It doesn't have to be a proprietary system. Possibly install a distribution box. However, one should have some experience when working with electricity.

A three-wire cable with constant current is initially not suitable for switching spots and possibly different circuits from the inside. How are the spots supposed to be switched at all? Extending it is rather the lesser problem.

A three-core cable with permanent power is initially not suitable for switching spots and possibly different circuits from the inside. How are the spots supposed to be switched at all? Extending is rather the smaller problem.

Ultimately, I thought about controlling the spots via a timer switch. Doesn’t such a thing exist? Actually, I hadn’t thought about it beforehand and thought that once my gardener lays my cable to different places accordingly, I could then consider what to do from there. Do I have to install a distribution box first to even have the possibility? I thought there would be appropriate lighting options here so that the spotlights can be controlled separately or possibly also by timer switch.

Ultimately, I was thinking about controlling the spotlights with a timer switch. Doesn't something like that exist?

There are socket columns with integrated timer switches. But since sunrise and sunset times change constantly, you might have to adjust the times all the time. Or you use some radio-controlled smart home solution. But I would have run five wires with at least one switched from inside.

Actually, I hadn’t thought about this in advance and thought that when my gardener lays my cable to different places, I can consider what to do from there. Do I first have to install a distribution box to even have a possibility? I thought that there would be corresponding lighting options here, so that the spotlights could be controlled separately or possibly also by timer switch.

Everything must be executed somehow waterproof. A separate RCD protection for outside would also be advantageous, so that if something trips the RCD, not immediately something inside the house is affected. Often such faults in the outdoor wiring (e.g. if water has entered somewhere) are only found days later, and meanwhile the circuit possibly cannot be put back into operation.

There are socket columns with integrated timers. But the sunrise and sunset times constantly change, so you might have to keep adjusting the times. Or you use some radio-controlled smart home solution. But I would have had five conductors installed with at least one conductor switched from the inside. Everything has to be done waterproof somehow. A dedicated RCD protection for outside would also be beneficial, so if something trips the RCD, nothing inside the house is immediately affected. Often, such faults in the exterior wiring (e.g., if water has entered somewhere) are only discovered days later and the circuit cannot be put back into operation in the meantime.

In fact, I had a 5-core underground cable, or rather, I have one that is switched by permanent power and an internal on/off switch. I had these cables extended, but only with 3-core, since my gardener is not an electrician and said he could only extend or lay 3-core. Now I have a 3-core cable hanging around outside.

That was exactly the issue I had with the RCD.

The cable was in water last summer and therefore tripped the RCD and shut down the living area. Until I realized it was the cable outdoors...

So it certainly makes sense that I connect the cable to a small distribution box with RCD, correct? From there I could go to a socket column, or from there also connect something via smart home control.