Date Code 20010731 Distributed Network Protocol (DNP) 3.00 G-19
SEL-352-1, -2 Instruction Manual
Object 113 is used to send data from the relay side to the Master side of the link. Master devices
may use only Function codes Read (FC=1). The relay uses only Function codes Response
(FC=129).
The procedure for accessing these objects is as follows. Master devices transmit data to relay
devices by writing one or more of object 112 to a relay using the Virtual Port number as the DNP
point number. Relays send information to the Master using the Virtual Port number by
responding to a Master READ (FC=1) request of object 113. Messages can flow in either
direction at any time, however the relay sends messages only at the request of the Master. There
are no explicit procedures for the initiation or conclusion of a VT session (i.e., implicit
connections exist by the mere presence of a VT-compatible Slave IED).
Virtual terminal supports all ASCII commands listed in the Command Summary at the end of
Section 8: Serial Port Communications and Commands. You do not need a password to login
to a virtual terminal session through a DNP port, but you will need the appropriate access levels
for setting changes and breaker operations. A virtual terminal session times out in the same way
as an ASCII session.
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