ABB Relion 620 Series, Руководство по применению

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Section 3
1MAC308145-MB E
RER620 application
58 RER620
Application Manual
• When a single phase has locked out, the reset timer will count down from its set value
in the recloser settings. If another phase becomes involved before the reset time
expires, that phase will operate one shot to lockout. If, alternatively, the reset timer
has expired, the additional involved phase will go through the full sequence of
programmed operations.
• In single-phase tripping, the phase fault current must be greater than the phase
element pickup for the single-phase trip to occur. If the fault current is above the
neutral setting, but below the phase setting, a three-phase trip will occur. o In the case
where both the phase and ground element pick up (all phases must be closed for
neutral pickup), the trip time for the involved phases will be based on the faster of the
phase trip or the ground setting.
• After a single phase trip or lockout operation, all ground tripping is de-energized.
This prevents nuisance tripping of adjacent phases afterwards, due to load imbalance.
3.4.1.2 OPUP Mode - Only Picked Up Phases
If OPUP is selected, any respective phase that detects fault current by the RER620 is
actuated to open the respective pole of the recloser. The option for OPUP also allows each
pole on the recloser to open independently if the RER620 detects fault current on any of
the other two phases.
For example, suppose that a fault is detected on phase B. The RER620 will sense this
pickup and initiate a binary output signal from the RER620 to the recloser, the recloser will
trip open phase B and await timing from the RER620 for subsequent reclose or lockout.
Now suppose that during the pickup and subsequent trip of phase B, the RER620 senses
another fault on phase A. The RER620 will detect that fault and initiate a binary output
signal from the RER620 to the recloser for pole A, the recloser will trip open phase A and
then await timing from the RER620 for reclose or lockout. Comparable sequences may
occur and operation of the RER620 will continue to operate for phase C or any
combination of phase(s) caused by excessive load or fault current.
3.4.1.3 OOAP Mode - One Or All Phases
In this mode, if a single-phase fault is detected or picked up on one pole, a single-phase
trip will occur as in the case of OPUP mode. However, if a combination of two or three
phases pickup or detect a fault, then the RER620 will initiate a binary trip output to the
recloser for all three poles to trip.
For example, consider a situation where the distribution load has motors connected onto
the distribution line. If a single-phase fault occurred on any phase of the line, the RER620
should initiate a trip of all three phases, OOAP, to prevent the three-phase motors from
single phasing. A three-phase motor may continue to run with the loss of a single-phase,
but it will overheat. In addition, a stopped three-phase motor that is attempting to start with
the loss of a single-phase will cause overheating in the motor. For this application, a
distribution line with three-phase motors should implement OOAP on single-phase faults.
Some common examples: