Echelon LONWORKS PLT-22, User Manual

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Example 3: Line-to-Earth (L-to-E), Non-Isolated Coupling Circuit
Figure 4.13 shows a schematic for a line-to-earth, non-isolated mains coupling
circuit. Table 4.7 lists component values and recommended suppliers/part numbers
for coupling to AC mains with a nominal line voltage in the range 100-240VAC. For
coupling to AC mains with a nominal line voltage in the range of 100-120VAC, refer
to table 4.8. This schematic may also be used for coupling to wiring other than AC
mains with AC or DC voltages of 250V
RMS
or less.
Transmit Amp
Receive
Front
End
PLT-22
C1
C2
L1
L2
TXOUT
RXIN
RXCOMP
L3
Line
Earth
D1
R1
F1
L4
C4
R2
C3
V
A
See
note
below
PROTECT
Inductors L1 and L3 should be
spaced >1cm (0.4”) apart to avoid
undesirable parisitic coupling.
Note: This optional circuit should be added to nodes with a nominal VA<12V or nodes that contain a
triac or SCR load switching device.
Figure 4.13 L-to-E, Non-Isolated Coupling Circuit Schematic
4-22 Coupling Circuits