WARNING
No plug shall be freely accessible in normal
operation due to safety reasons.
Installation
ADVICE
The EDS500 devices are protection class
II device with functional earthing.
Correct functional earthing is
accomplished by snapping the modem
on the properly earthed DIN-rail (making
contact to backside functional earth
contacts) and additionally connecting
terminal X1-2 (SHIELD) to an earthing
terminal on the DIN-rail.
WARNING
Functional earthing must be done
properly in order for the overvoltage
protection of the modem to work
properly.
"Fig. 4: Schematic installation drawing" shows a
schematic drawing of the correct installation of the
modem. X1-2 has to be connected to functional earth.
Terminal X1-1 is connected to the positive terminal and
X1-3 to the negative terminal of a DC power supply.
The communication line can be either connected in
two-wire or four-wire configuration. For two-wire
configuration connect terminal X3-1 and X3-2 to the
pair of wires. For four-wire configuration connect
terminal X3-1 and X3-2 to the pair of wires used for
transmit direction and X3-3 and X3-4 to the pair used
for receive direction.
The internal transformers of the 500FSD20 have
a galvanic isolation of 3 kV. If a higher level of
protection is needed, additional isolation low-
frequency (LF) transformers have to be used.
See "Fig. 5: Communication line connection by LF
transformer (two-wire connection)" and "Fig. 6:
Communication line connection by LF transformer
(four-wire connection)" for the installation scheme.
Finally, the serial interface has to be connected to the
local data termination equipment (DTE) by connecting
X2 of the 500FSD20 to the serial interface of the DTE
by a shielded serial cable, e.g. 500CAB08.
