ᐅ Actual size of the telecommunications cable single-conduit entry?

Hello,
I am a bit confused about the statements from the telecom provider. They require either a DN50 or DN75 conduit. However, when I look at a Doyma single-duct entry seal Quadro-Secura E1/wide, it accommodates telecom cables with sizes of 2x 5 - 7mm (0.2 - 0.3 inches), 2x 7 - 13mm (0.3 - 0.5 inches), and 1x 12 - 16mm (0.5 - 0.6 inches). Similarly, for the multi-duct entry seal Quadro-Secura Nova 1/wide, the cable openings are not that large but include 2x 5 - 7mm (0.2 - 0.3 inches), 4x 7 - 13mm (0.3 - 0.5 inches), and 1x 13 - 21mm (0.5 - 0.8 inches). So, these seem much smaller than what is specified. How large are telecom cables or possibly future fiber optic cables expected to be? Is a single-duct entry seal definitely sufficient? I would prefer that option because I only need power and telecom lines (water is supplied at the other side of the house).

The fiber optic conduit (into which the fiber is later blown) is 10mm (0.4 inches) thick and is practically the same size everywhere. My telecom copper/DSL cable is also 10mm (0.4 inches) thick, but I do not know if this varies regionally.

The requirement for an empty conduit obviously comes from the need to pull the cable through without digging. Either the empty conduit ends before entering the building, in which case the opening only needs to match the cable diameter, or you use special building entry sleeves designed for empty conduits. These seal the conduit from both the inside and outside.

For a straighter route, an M25 conduit would be completely sufficient (straight, without bends, etc.). I believe we also installed M32, which then transitioned to DN75 (multi-service).

Attached is a photo of the final telecom cable (Brandenburg, no fiber optic). It is as thick as 5x2.5mm² (about 1cm (0.4 inches) in diameter).

To put it bluntly. On the left, you see all the doorbell wires from the telecom cable, and on the right, the two small wires (doorbell wires) that eventually connect to the router to enable DSL 50 Gbit, etc.

In theory, a small conduit like a drinking straw would be sufficient as an empty duct.

Great, thanks. So, in your case, the empty conduit itself is not sealed against the multi-utility connection, correct? That’s what Fuchur was referring to as a possibility, but I think it’s rarely actually done?

We ordered our multi-conduit with 3m (10 feet) of empty conduit extending outside, bridging the remaining 5m (16 feet) up to the property boundary with M32. The trench was intended to be opened only once, when water and electricity were installed. We sealed the M32 with well foam inside the DN75 pipe. We do not expect any standing water at the M32/DN75 transition or any groundwater pressure. Therefore, in my view, this sealing is sufficient for our case (a pragmatic approach). We have sandy soil, where you can literally observe the water soaking into the ground simultaneously.