Monitored Data - ABB REG650 Technical Manual

Section 8
Current protection
Table 127: NS2PTOC (46I2) Non group settings (basic)
Name Values (Range)
GlobalBaseSel 1 - 6
8.9.6
8.9.7
240
Unit Step
- 1

Monitored data

Table 128: NS2PTOC (46I2) Monitored data
Name Type
NSCURR REAL
Operation principle
The negative sequence time overcurrent protection for machines (NS2PTOC, 46I2)
function directly measures the amplitude of the negative phase sequence component of
the measured current. NS2PTOC (46I2) sets the PICKUP, PU_ST1 or PU_ST2 outputs
active and starts to count trip time only when the measured negative sequence current
value rises above the set value of parameters I2-1> or I2-2> respectively.
To avoid oscillation in the output signals, a certain hysteresis has been included. For
both steps, the reset ratio is 0.97.
Step 1 of NS2PTOC (46I2) can operate in the Definite Time (DT) or Inverse Time
(IDMT) mode depending on the selected value for the CurveType1 parameter. If
CurveType1= Definite, NS2PTOC (46I2) operates with a Definite Time Delay
characteristic and if CurveType1 = Inverse, NS2PTOC (46I2) operates with an Inverse
Time Delay characteristic. Step 2 can only operate in the Definite Time (DT) mode.
The characteristic defines the time period between the moment when measured
negative sequence current exceeds the set pickup levels in parameter I2-1> or I2-2>
until the trip signal is initiated.
Definite time delay is not dependent on the magnitude of measured negative sequence
current. Once the measured negative sequence current exceeds the set level, the
settable definite timer t1 or t2 respectively, starts to count and the corresponding trip
signal gets activated after the pre-set definite time delay has elapsed. Reset time in
definite time mode is determined by the setting parameters tResetDef1 or tResetDef2
respectively. If NS2PTOC (46I2) has already picked up but not tripped and measured
negative sequence current goes below the pickup value, the pickup outputs remains
active for the time defined by the resetting parameters.
A BLOCK input signal resets NS2PTOC (46I2) momentarily.
Default Description
1 Selection of one of the Global Base Value
groups
Values (Range) Unit
- A
1MRK 502 043-UUS B
Description
Negative sequence current in
primary amps
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