Toshiba GR200 Series Instruction Manual page 1426

Interoperability
11.4.3
The IEC 60870-5-103 protocol provides a physical layer and an application layer for the
communication to secure the interoperability.
Physical layer
(i)
Either an electrical or an optical interface† is defined in the IEC 60870-5-103 standard.
Electrical interface in the RS-485
A maximum number of 32 relays is possible in the IEC 60870-5-103 standard.
Optic interface
Several optic communication modules are available
†Note: Either interface is provided with a communication module in the IED; the
specification is discussed separately. See chapter
processing and communication module
Application Layer
(ii)
The following layers are provided on the application layer:
COMMON ADDRESS of ASDU
One COMMON ADDRESS OF ASDU (identical with station address)
.
- 1403 -
6F2S1914 (0.49)
Technical description: Signal
GRL200 (Soft 033 & 037)