ABB REU 610 Technical Reference Manual

Also see for REU 610: Installation manual Technical reference manual Operator's manual Technical reference manual Operator's manual

Contents

ABB REU 610 Technical Reference Manual Manual pdf 29 page image

29The CBFAIL unit generates a trip signal via output PO2 when the set operatetime of CBFAIL expires.The CBFAIL can be triggered internally via protection functions. All thesignals, except external trip, routed to output PO1 trigger the CBFAIL. If thefault situation is not cleared when the set operate time has elapsed, theCBFAIL generates a trip signal via output PO2.The CBFAIL can also be selected to be triggered externally by applying adigital input signal to the relay, if the maximum of all three phase-to-phasevoltages is above 0.15× U n (VT). If the fault situation is not cleared when theset operate time has elapsed, the CBFAIL generates a trip signal via outputPO2.Internal triggering is selected by activating the CBFAIL in SGF1/6 andexternal triggering by activating the CBFAIL in SGB1...5/7.Normally, the CBFAIL controls the upstream circuit breaker. However, it canalso be used for tripping via redundant trip circuits of the same circuitbreaker.5.1.4.6. Inverse definite minimum time characteristcsEach of the overvoltage and undervoltage elements can be given either adefinite-time or an inverse definite minimum time (IDMT) characteristic. Thefollowing setting parameters determine the operation mode of the overvoltageand undervoltage protection elements:Table 5.1.4.6.-1 Operation mode setting parametersProtectionelementParameter Setting59P-1 S3 0 = definite time1 = curve A2 = curve B59P-2/47 S11 0 = definite time1 = curve A2 = curve B27P-1 S15 0 = definite time1 = curve C27P-2/27D S22 0 = definite time1 = curve CAt IDMT characteristic, the operate time of the element is dependent on thevoltage value: the greater the deviation from the setting value, the shorter theoperate time. Three time/voltage curve groups are available: A, B and C.An overvoltage element picks up when the measured voltage exceeds thesetting value of the element. An undervoltage element picks up when themeasured voltage drops below the setting value of the element. However, the1MRS755972 Voltage RelayTechnical Reference Manual - ANSI VersionREU 610