Basler BE1-CDS220, Instruction Manual

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4-42 Protection and Control BE1-CDS220
Retrieving Virtual Selector Switches Status from the Relay
The state of each virtual selector switch can be determined from the optional HMI Screen 1.4.3,
\STAT\OPER\43. This information is also available through the ASCII command interface by using the
RG-STAT command. See Section 6,
Reporting and Alarm Functions, General Status Reporting , for more
information.
HMI Screens 2.1.1 through 2.1.8 provide switch control and can display the status of their respective
switches. ASCII command CO-x43 returns the state of each virtual selector switch in a read-only mode.
See the previous Example 1.
101 - Virtual Breaker Control Switches
The virtual breaker control switch (shown in Figure 4-42) provides manual control of a circuit breaker or
switch without using physical switches and/or interposing relays. Both local and remote control is
possible. A virtual switch can be used instead of a physical switch to reduce costs with the added benefit
that the virtual switch can be operated both locally from the HMI and remotely from a substation computer
or modem connection to an operator's console. The BE1-CDS220 relays provide one Virtual Breaker
Control Switch (101).
Figure 4-42. Virtual Breaker Control Switch Logic Block
The virtual breaker control switch emulates a typical breaker control switch with a momentary close,
spring return, trip contact (output 101T), a momentary close, spring return, close contact (output 101C),
and a slip contact (output 101SC). The slip contact output retains the status of the last control action. That
is, it is FALSE (open) in the after-trip state and TRUE (closed) in the after-close state. Figure 4-43 shows
the state of the 101SC logic output with respect to the state of the 101T and 101C outputs.
When the virtual control switch is controlled to trip, the 101T output pulses TRUE (closed) for
approximately 200 milliseconds and the 101SC output goes FALSE (open). When the virtual control
switch is controlled to close, the 101SC output pulses TRUE (closed). The status of the slip contact output
is saved to nonvolatile memory so that the relay will power up with the contact in the same state as when
the relay was powered down.
Figure 4-43. Virtual Breaker Control Switch State Diagram
BESTlogic Settings for Virtual Breaker Control Switches
BESTlogic settings are made from the BESTlogic Function Element screen in BESTCOMS. Figure 4-44
illustrates the BESTCOMS screen used to select BESTlogic settings for the 101 V irtual Breaker Control
Switch element. To open the BESTlogic Function Element screen for the 101 Virtual Breaker Control
Switch element, select Virtual Switches from the Screens pull-down menu. Then select the BESTlogic
button for the Virtual Breaker Control Switch. Alternately, settings may be made using the SL-101 ASCII
command.