Rockwell Automation 865 Differential Protection Relay - Manual (Page 73)

Protection Functions 3-29
865-UM001A-EN-P – July 2009
Binary Output
The binary output (BO) on the arc option card (see Chapter 8) can be
used to give the light indication signal or any other signal or signals
to another relay's binary input to build selective arc protection
systems. Selection of the BO connected signal(s) is done with the
output matrix (See Chapter 5). BO is an internally wetted 48 Vdc
signal for BI of other Allen-Bradley relays or dedicated arc
protection devices by Allen-Bradley.
Delayed Light Indication Signal
There is a delayed light indication output signal available for
building selective arc protection systems. Any light source
combination and a delay can be configured. The resulting signal is
available in the output matrix to be connected to BO, output relays
etc.
Pick Up Scaling
The per unit (pu) values for pick up setting are based on the current
transformer values.
ArcI>: 1 pu = 1xI
N
= rated phase current CT value
ArcI’>: 1 pu = 1xI’
N
= rated phase current CT value
ArcI 01 >: 1 pu = 1xI 01N = rated residual current CT value
for input I
01
ArcI
02
>: 1 pu = 1xI
02N
= rated residual current CT value
for input I
02
Table 3.17 – Parameters of Arc Protection Stages Arcl>, Arcl’>, Arcl 01 A,
Arcl 02 > (50 ARC / 50N ARC)
Parameter Value Unit Description Note
Status –
Start
Trip
Current status of the stage
Light detected according ArcIn
Light and overcurrent detected
F
F
LCntr Cumulative light indication counter. S1,
S2 or BI. C
SCntr Cumulative light indication counter for
the selected inputs according parameter
ArcIn C
TCntr Cumulative trip counter C
Force Off
On
Force flag for status forcing for test
purposes. This is a common flag for all
stages and output relays, too.
Automatically reset by a 5-minute
timeout. Set
ILmax
I’Lmax
Io1
Io2 Value of the supervised signal
Stage ArcI>
Stage ArcI’>
Stage ArcI
01 >
Stage ArcI 02 >