Basler BE1-951 Instruction Manual
Also see for BE1-951: Application guideManualInstruction manual
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         | |
Contents
| 
4-76 BE1-951 Protection and Control 9328900990 Rev LVIRTUAL SWITCHES43 - Virtual Selector SwitchesBE1-951 relays have four virtual selector switches that can provide manual control, locally and remotely,without using physical switches and/or interposing relays. Each virtual switch can be set for one of threemodes of operation to emulate virtually any type of binary (two position) switch. An example would be anapplication that requires a recloser or 51N ground cutoff. The traditional approach might be to install aswitch on the panel and wire the output to a contact sensing input on the relay. Instead, a virtual switchcan be used to reduce costs with the added benefit of being able to operate the switch both locallythrough the HMI and remotely from a substation computer or through a modem connection to a remoteoperator’s console.The state of the switches can be controlled from the HMI or ASCII command interface. The BESTlogicmode setting can set control actions. When set for the On/Off/Pulse mode, each switch can be controlledto open (logic 0), close (logic 1), or pulse such that the output toggles from its current state to theopposite state and then returns. Additional modes allow the switch operation to be restricted. In theOn/Off mode, the switch emulates a two-position selector switch, and only open and close commands areaccepted. In the Off/Momentary On mode, a momentary close, spring return switch is emulated and onlythe pulse command is accepted. Because switch status information is saved in nonvolatile memory, therelay powers up with the switches in the same state as when the relay was powered down.Each virtual selector switch function block (see Figure 4-71) has one output: 43, 143, 243, or 343. Theoutput is TRUE when the switch is in the closed state; the output is FALSE when the switch is in the openstate. Since both the output and the inverse of the output of these switches can be used as many timesas desired in your programmable logic, they can emulate a switch with as many normally open andnormally closed decks as desired.43Mode0-Disable1-On/Off/Pulse2-On/Off3-Off/Momentary On43 AUXSWITCHD2861-0503-13-00Figure 4-71. Virtual Selector Switches Logic BlockUser specified labels could be assigned to each virtual switch and to both states of each switch. In theprevious differential cutoff switch example, you might enable one of the switches in BESTlogic as On/Offand connect the output of that switch to the Block input of the 51P protection element block. This woulddisable the differential when the switch is closed (logic 1) and enable it when the switch is open (logic 0).For the application, you might set the switch label to be 51_CUTOFF (10 character maximum). Theclosed position on the switch might be labeled DISABLD (7 character maximum) and the open positionmight be labeled NORMAL. Section 7, BESTlogic Programmable Logic, has more details about settinguser programmable names for programmable logic variables.BESTlogic Settings for Virtual Selector SwitchesBESTlogic settings are made from the BESTlogic Function Element screen in BESTCOMS. Figure 4-72illustrates the BESTCOMS screen used to select BESTlogic setting for the Virtual Switch element. Toopen the BESTlogic Function Element screen for Virtual Switch, select Virtual Switches from the Screenspull-down menu. Then select the BESTlogic button for the 43, 143, 243, or 343 element. Alternately,settings may be made using SL- |
This manual is suitable for:
manualsdatabase
Your AI-powered manual search engine