ABB RELION 670 Series Applications Manual page 155

1MRK 505 337-UUS A
IMinx : Minimum operate current in % of IB for all inverse time characteristics, below which no
operation takes place.
IMinx : Minimum pickup current for step x in % of IBase . Set IMinx below Pickupx for every step to
achieve ANSI reset characteristic according to standard. If
the ANSI reset works as if current is zero when current drops below
txMin : Minimum trip time for all 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 can never be shorter than the setting. Setting range: 0.000 - 60.000s in steps of
0.001s.
MultPUx : Multiplier for scaling of the current setting value. If a binary input signal ENMULTx
(enableMultiplier) is activated the current operation level is increased by this setting constant.
Setting range: 1.0-10.0
Trip time
tx
txMin
ANSI10000058 V1 EN-US
Figure 78: Minimum pickup current and trip time for inverse time characteristics
In order to fully comply with the definition of the curve, the setting parameter
a value equal to the operating time of the selected inverse curve for twenty times the set current
pickup value. Note that the operate time is dependent on the selected time multiplier setting
ResetTypeCrvx : The reset of the delay timer can be made as shown in Table 27.
Table 27:
Curve name
Instantaneous
IEC Reset (constant time)
ANSI Reset (inverse time)
Application manual
Reset possibilities
Curve index no.
1
2
3
IMinx is set above Pickupx for any step
IMinx .
Pickup current
ANSI10000058-1-en.vsdx
Section 7
Current protection
txMin shall be set to
kx .
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