ABB RELION Series, Technical Manual

Page: 109 / 804

3.13.3.2 Functionality
The ULTVTR function is used in the receiver application to perform the supervision
for the sampled values and to connect the received analog phase voltage inputs to the
application. Synchronization accuracy, sampled value frame transfer delays and
missing frames are being supervised.
The typical additional operate time increase is +2 ms for all the
receiver application functions (using either local or remote samples)
when SMV is used.
3.13.3.3 Operation principle
The
ALARM
in the receiver is activated if the synchronization accuracy of the sender
or the receiver is either unknown or worse than 100 ms. The output is held on for 10
seconds after the synchronization accuracy returns within limits.
ALARM
is activated when two or more consecutive SMV frames are lost or late. A
single loss of frame is corrected with a zero-order hold scheme. In this case the effect
on protection is considered negligible and the
WARNING
or
ALARM
outputs are not
activated. The output is held on for 10 seconds after the conditions return to normal.
The SMV Max Delay parameter defines how long the receiver waits for the SMV
frames before activating the
ALARM
output. This parameter can be accessed via
Configuration/System/Common . Waiting of the SMV frames also delays the local
measurements of the receiver to keep them correctly time aligned. The SMV Max
Delay values include sampling, processing and network delay.
The
MINCB_OPEN
input signal is supposed to be connected through a protection
relay's binary input to the NC auxiliary contact of the miniature circuit breaker
protecting the VT secondary circuit. The
MINCB_OPEN
signal sets the
FUSEF_U
output signal to block all the voltage-related functions when MCB is in the open state.
The
WARNING
output in the receiver is activated if the synchronization accuracy of
the sender or the receiver is worse than 4 μs. The output is held on for 10 seconds after
the synchronization accuracy returns within limits. If the protection relay supports
frequency adaptivity and it is enabled, the
WARNING output is also activated when the
adaptivity is not ready.
The
WARNING
output is always internally active whenever the
ALARM
output is
active.
The receiver activates the
WARNING
and
ALARM
outputs if any of the quality bits,
except for the derived bit, is activated. When the receiver is in the test mode, it accepts
SMV frames with test bit without activating the
WARNING
and
ALARM
outputs.
1MRS758755 A
Section 3
Basic functions
REC615 and RER615 103
Technical Manual