Basler BE1-CDS220, Instruction Manual

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BE1-CDS220 Application 8-53
To prevent the output relay contacts from opening prematurely, a 200 millisecond hold timer can be
selected with the SG-HOLDn=1 command. Refer to Section 3, Input and Output Functions, Outputs,
Programmable Hold Timer, for more information on this feature. If the protection engineer desires seal-in
logic with feedback from the breaker position logic, he can provide this feature by modifying the BESTlogic
expression for the tripping output. To do this, use one of the general purpose timers, 62 or 162, and set it
for mode 1 (Pickup/Dropout Timer). Set the timer logic so that it is initiated by the breaker position input,
and set the timer for two cycles pickup and two cycles dropout. Then AND the timer output with the
tripping output (VO1) and OR it into the expression for the tripping output. The same can be done for the
closing output. See Figure 8-18 for the seal-in logic diagram and Seal-In Logic Example that follows. This
example is based on the BASIC-TX preprogrammed logic scheme.
OUTPUT
LOGIC
OPTO
OUTPUT
LOGIC
INI
62
BLK
IN1
52b
+
+
62
-
TRIPPING
LOGIC
52TC
CLOSING
LOGIC
52CC
OUT2
OUT1
+
-
52a 52b
52TC
52CC
D2590-10
03-23-98
VO1
VO2
VO7
VO6
Figure 8-18. Output Seal-In Logic Diagram
Table 8-32. Output Contact Seal-in Logic
Command Purpose
SG-HOLD1=0 Turn off the hold timer for output 1.
SL-62=1,IN1,0 Set the timer logic to mode 1 (pickup/dropout), IN1 to initiate, no blocking.
S#-62=2c,2c Set the pickup (2 cycles) and dropout (2 cycles) times.
VO1=87RT+87UT+VO1
∗
/62
Set the tripping logic for restrained 87 or unrestrained 87 or virtual output 1 and
not 62.
VO2=87RT+87UT+VO7 Set the closing logic for restrained 87 or unrestrained 87 or virtual output 7.
VO6=VO1
∗
/62 Set the virtual output 6 logic to VO1 and not 62.
VO7=VO2
∗
62 Set the virtual output 7 logic to VO2 and 62.
E Exit.
Y Save settings.
Latching a Tripping Contact
On occasion, an application will call for latching an output contact. As an example, assume that a BE1-
CDS220 is used for protection of a radial transformer as shown in Figure 8-19. The user wants to trip and
lockout the high-side circuit switcher for a differential trip; but, not for an overcurrent trip. He does not want
the transformer to be re-energized until someone locally checks and resets the relay.
Referring to Figure 8-20, which is an adaptation of BASIC-87 logic, an 87 trip will cause VO7 to go true.
This causes OUT1, OUT2, and OUT3 to close and OUT5 which would be wired in the close circuit, to
open. VO7 is sealed in through VO8 and holds the outputs in this condition. The optional front panel HMI