Linkage system (coupling system) are classified according to the association of inductive and capacitive association. Because the trap line (line trap) is a high impedance to the carrier frequency, then the trap is in series with the power transmission line in order to improve the characteristics of the distribution of the carrier waves.
Inductive association through the air using a conductor mounted parallel to and at a certain distance from the transmission line; This system is used to link the PLC equipment to the transmission line at high frequencies. The system is now rarely used.
There are two types of association with the capacitor. The first is a system of association with the type of tuning capacitor (tuning type), in which the tuning circuit (including capacitors hook) linked in series with the transmission line. The second is a system wide association with capacitor type filter (filter), where the association with the channel PLC equipment is done through a capacitor filter and hook hook second system is now widely used, see Figure 5-87.
Capacitors hook separating the transmission line from PLC equipment and joint hook filter is a four-pole network is continuing high frequency. Used usually is oil filled paper capacitors as shown in Figure -88, with capacitance
electrostatic 0.001 to 0.002 μF.
As the filter is used “band-pass filter”. The circuit of this type of transformer as shown in Figure 5-87 (b). Lose in the frequency range passed (passing band) of 1 – 1.5 dB down.
Drain trap consists of a primary coil which forwards the commercial frequency, tuning tools that provide the desired high frequency impeclansi and arrester protects the equipment.
A: Trap Line (Line Trap)
B: Capacitors Hook (Coupling Capacitor)
C: Filters Hook (Coupling Filter)
Specification:
LT … Trap Line (Line Trap)
CC … Capacitor Coupling Capacitors Hooking)
TR … Equipment Carrier (PLC)
He = additional losses in terms of linkage phase-ground usually taken 5 dB.