ABB RELION 650 SERIES, Applications Manual

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tx: Definite time delay for step x. The definite time tx is added to the inverse time when inverse
time characteristic is selected.
Pickup"x": Operate residual current level for step x given in % of IBase.
TDn: Time multiplier for inverse time delay for step n.
IMinn: Minimum operate current for step n in % of IBase. Set IMinn below Pickupx for every step to
achieve ANSI reset characteristic according to standard. If IMinn is set above Pickupx for any step
then signal will reset at current equals to zero.
tnMin: Minimum operating time for inverse time characteristics. At high currents the inverse time
characteristic might give a very short operation time. By setting this parameter the operation time
of the step
n can never be shorter than the setting.
IEC09000164-2
Operate time
Current
tx
tnMin
IMinn
IEC09000164 V2 EN-US
Figure 33: Minimum operate current and operate time for inverse time characteristics
In order to fully comply with curves definition the setting parameter
txMin shall be set to the value
which is equal to the operate time of the selected IEC inverse curve for measured current of
twenty times the set current pickup value. Note that the operate time value is dependent on the
selected setting value for time multiplier
TDn.
7.2.3.2 Common settings for all steps
M15282-81 v7
tx: Definite time delay for step x. Used if definite time characteristic is chosen.
AngleRCA: Relay characteristic angle given in degree. This angle is defined as shown in figure
34 .
The angle is defined positive when the residual current lags the reference voltage (Vpol = 3V
0
or V
2
)
1MRK 505 287-UUS B Section 7
Current protection
Busbar protection REB650 83
Application manual
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