Functions Overview; Applications; Connectivity; Modulation - ABB HITACHI EDS500 Series Manual

Functions overview

3.2 Functions overview
3.2.1

Applications

The wide area of applications enable the EDS500 series - FSK modems to be used in any cost-
efficient environment using serial communication. Its simplicity and robustness provide ease
of installation as well as long product lifetime.
Analog serial modems of the EDS500 series allow to implement real physical two-or-four wire
shared bus topologies (all modems connect to the same cable) with ranges of up to 30 km.
The compact case without moveable parts for easy installation on DIN rail, a wide range
power supply (24...60 V) with small power consumption, extended temperature range and
integrated overvoltage protection complete the concept of the EDS500 series - FSK modems.
3.2.2

Connectivity

The EDS500 series of analog modems consists of multiple products allowing to establish
wide area connections via customer-owned copper cables. The devices provide a serial
interface (V.24 / RS-232) and a combined two-/four-wire line interface.
A variety of communication schemes are supported to provide connectivity to clients and
other communication devices:
• 24 channels each 50 bps (ITU-T/CCITT R.35)
• 12 channels each 100 bps (ITU-T/CCITT R.37)
• 6 channels each 200 bps (ITU-T/CCITT R.38a)
• 2 channels each 600 bps
• 1 channel 1200 bps (ITU-T/CCITT V.23)
• 1 channel 2400 bps
• 1 channel 9600 bps
500FSD devices can be used in point-to-point (end-to-end) and multidrop (partyline)
applications. The transmission is transparent, supporting byte oriented (e.g. IEC 60870-5-101,
IEC60870-5-103, IEC 62056-21, RP570/71, DNP, Modbus, SEAB 1F, TG809 or SINAUT) as well as
pulse based (e.g. quantity pulse or relay contacts) transmission procedures. The specified bit
rate defines the maximum bit rate allowed, lower bit rates can still be transmitted.
3.2.3

Modulation

EDS500 series modems rely on FSK based modulation technology with adjustable
attenuation and equalizer to compensate line characteristics. 500FSD20 is able to report bad
line quality via an isolated alarm relay.
3.2.4

Multi-channel

500FSD10 and 500FSD11 are cost-efficient modems allowing to communicate on a 1200
bps V.23 or 9600 bps channel on one wire pair. The device 500FSD20 is in addition able to
operate in multi-channel environments allowing multiple separate data streams on the same
cable. Using this frequency multiplexing based technology it is possible to separate and run
multiple services on a single two- or four-wire cable. This can also be used to separate the
transmit and receive channels to allow full-duplex on two-wire installations.
12
System concept
1KGT151042 V000 1