Basler BE1-CDS220, Instruction Manual

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BE1-CDS220 Application 8-55
Latching a Programmable Logic Alarm or Creating a Pseudo Target
Sometimes, a user may want the relay to annunciate and latch for a user defined condition originating
internally or externally to the relay. This can be accomplished using the user programmable labels
functionality and the virtual outputs VO13, VO14, or VO15. These virtual outputs are also programmable
alarm variables. If one of these three logic expressions is true and is also programmed as a major or
minor alarm point, the programmable label will appear on the alarms screen of the optional front panel
HMI display.
The application of this is best illustrated with an example. Use the application shown in Figure 8-19 and
8-20. The user wants to trip and lockout the high side circuit switcher (CSW) for a Sudden Pressure Relay
(63_SPR) trip. The SPR trip is to be supervised and sealed in via the BE1-CDS220 relay. Since this is an
external function, it is desired that the relay annunciate that the trip came from the SPR instead of an
internal protective element.
Referring to Figure 8-20, when the SPR contact closes, IN4 will cause VO13 to go true. This causes
OUT1, OUT2, and OUT3 to close and OUT5 which would be wired in the close circuit, to open. VO13 is
sealed in through VO9 which holds the outputs in this condition. The HMI LCD automatically goes to the
alarms screen if VO13 is programmed as a major or minor alarm per the automatic display priority
function. The LCD displays the user programmable label for VO13 which in this example might be
programmed to be SN-VO13=SPR_TRIP.
When the operator presses the reset key while the display is on the alarms screen, the ARSTKEY logic
variable goes high and breaks the seal in of logic expressions VO13 and VO9. Outputs OUT1, OUT2, and
OUT3 will then open and OUT5 will close.
Refer to Section 6, Reporting and Alarm Functions for more information on programmable alarms. Refer to
Section 10, Human-Machine Interface for more information on Automatic Display Priorities.
Logic Settings Associated With Figure 8-20
SL-87=1,0
SL-51P=1,0; SL-51N=1,0; SL-51Q=1,0
SL-VO1=VO7+VO13
SL-VO2=VO7+VO13
SL-VO3=VO7+VO13
SL-VO4=51PT+51NT+51QT
SL-VO5=/VO7+/VO13
SL-VO6=ALMMAJ
SL-VO7=87RT+87UT+VO8
SL-VO8=VO7*/TRSTKEY
SL-VO9=VO13*/ARSTKEY
SL-VO11=51PT+51NT+51QT+87RT+87UT
SL-VO12=87UT+51PPU+51NPU+51QPU+87RPU
SL-VO13=IN4+VO9