Schweitzer Engineering Laboratories SEL-421-4, Instruction Manual

Page: 1463 / 1518

19.13
Date Code 20171006 Instruction Manual SEL-400 Series Relays
Remote Data Acquisition
IEC 61850-9-2 Sampled Values (SV)
erence stream. The SVND mm analog quantities indicate the measured channel
delay of each subscription and are compared with the Port 5 CH_DLY setting to
generate an alarm condition as described in the following.
The SVSALM Relay Word bit is a general purpose alarm that will assert for the
following conditions:
➤
The SV subscriber has lost sync with the device providing its
reference stream
➤
One or more subscribed SV streams network delays exceed the
CH_DLY setting
➤
One or more subscribed SV streams are no longer being received
(lost)
➤
One or more subscribed SV streams have a subscription status
SVS
mm OK bit that is not set.
The SV subscriber also provides analog channel status Relay Word bits, which
are useful for supervising protection based on the state of SV communications for
each current and voltage channel. These bits include
nnn OK and nnn BK bits,
where nnn is the product-specific current or voltage channel that can potentially
be mapped to data from an incoming SV stream, for example, IAW, IBW, ICW,
VAY, VBY, VCY, etc. in the SEL-421 SV Subscriber Relay. The
nnn OK bits
asserts for all data channels that are mapped to a subscribed SV stream and have
data actively being received from it. The
nnn BK bits are the inverse of the
nnn OK bits.
See Section 5: Protection Functions of the product-specific manual for more
information on SV status logic.