Inductive Coupler CMC 100
The dedicated Cipunet® Distribution Line Carrier solution is completed through an improved signal coupling philosophy.
Effective coupling of a narrowband digital data signal to electrical power line with low power losses directly influences costs, performance and reliability of a complete system. Cipunet®’s product portfolio provides inductive couplers for cable sheath coupling as well as capacitive couplers for phase coupling.
A major effort in field trials has been made to ensure optimal inductive coupling to the cable sheath. Where underground cables are used, this method provides a highly cost-effective solution.
The capability to communicate between capacitive couplers on unshielded MV lines and inductive couplers on shielded MV cables without additional hardware installations offers the optimal coupling depending on the specific line, cable and earth conditions. The interoperability of the two coupling methods in the Medium Voltage Network is a major advantage of the Cipunet® system.
The compact and cost effective CMC 100 Distribution Line Carrier coupler uses the method of inductive coupling to the cable sheath.
This method offers decisive advantages:
- Low cost
- Very easy to install
- Ideal for urban areas
- Independent of voltage level
- Low space requirements
- Operates over the full CENELEC frequency range assigned to power utilities
- Minimal signal attenuation
- Installed in the powerless earth path of the cable shield
Principle of operation
The inductive coupler CMC 100 inserts the primary winding of a transformer in the earth path of the cable sheath. The modulated signal is applied to the secondary winding of the transformer by simply connecting the CMC 100 to CMM75 and CMM2500 Modems via a shielded 2-wire cable. The transformer provides both galvanic insulation as well as impedance transformation. The primary winding withstands both the high current occurring during a double ground fault and the screen current under normal operation.