Wiring Loxone Tree
A Loxone Cat 7 cable is recommended for Loxone Tree cabling. The green/white wire pair is used for the Tree and the orange/white wire pair for the 24V DC supply. The remaining 2 wire pairs remain free and can be used for other functions. The shield of the cable does not need to be earthed.
The maximum cabling length per branch is 500m.
The maximum line length of 500m refers to Tree, NOT to the line length of the 24V power supply. Here the maximum length will be a little shorter due to the voltage drop.
With Loxone Tree, you can use a wide variety of cabling topologies.
We reccomend to run a cable into the room and then in the within room itself from this point the remaining Tree devices can be connected. This “first node” is most commonly the motion sensor but this is not a requirement.
- That a maximum of 50 devices can be connected per tree branch,
- That the Tree branches left and right can not be connected together
- That a Tree branch must never be wired as a ring.
VOLTAGE DROP CALCULATIONS
The Loxone Cat 7 cable has a cross-section of 0.258 mm². The voltage drop can be determined using the following formula:
ΔU = I RR II (((2 LL ρρ) / A)
I … current [A]
L … cable length [m]
A … cable cross section [mm²]
a = 0.258 for the Loxone Cat 7 cable
ΔU … voltage drop [V]
ρ … specific material resistance [(Ω * m) / mm²]
ρ = constant 0.0172 for copper)
The 24V supply voltage minus the calculated voltage drop must not exceed the min. Input voltage of the Tree product. In practice, voltage drops of approx. 3% are applied.
EXAMPLE FOR ACTUATOR
Max. Current from one actuator Tree: 62.5mA
Number of actuators: 15pce with max 5pc simultaneously in
operation Cable length: 20m
cross section Cat 7 cable: 0.258mm²
ΔU = I · (((2 x L · ρ) / A)
ΔU = 0.3125A · ((2 x 20m x 0.0172Ω * m / mm 2) / 0.258mm 2)
ΔU = 0.83V
The voltage drop of 0.83V is still permissible for the actuator Tree.