Technical Data - ABB RELION REX640 Technical Manual

Section 4
Protection functions
4.8.3.10
4.8.4
4.8.4.1
4.8.4.2
4.8.4.3
976

Technical data

Table 915: DQPTUV Technical data
Characteristic
Operation accuracy
Start time 1)2)
Reset time
Reset ratio
Operate time accuracy
Suppression of harmonics
Start value = 0.05 × S
1) , reactive power before fault = 0.8 ×
n
times, results based on statistical distribution of 1000 measurements
2) Includes the delay of the signal output contact
Underpower factor protection MPUPF
Identification
Function description
Underpower factor protection
Function block
GUID-A55CFB74-2481-45F5-9B0F-CEC2FB1FBF72 V1 EN
Figure 529: Function block
Functionality
The under power factor function MPUPF is used to provide out-of-step and loss of, or
under excitation protection for small synchronous motors and generators. The
function calculates the power factor and uses a threshold of under power factor as an
indication of an out-of-step and/or loss of excitation condition.
Value
Depending on the frequency of the measured
current and voltage:
f ±2 Hz
n
Reactive power range |PF| <0.71
Power:
±3.0% or ±0.002 × Q
Voltage:
±1.5% of the set value or ±0.002 × U
Typically 46 ms
<50 ms
Typically 0.96
±1.0% of the set value or ±20 ms
DFT: -50 dB at f = n × f
Start value , reactive power overshoot 2
IEC 61850 IEC 60617
identification identification
MPUPF PF<
1MRS759142 C
n
n
, where n = 2, 3, 4, 5,...
n
ANSI/IEEE C37.2
device number
55U
REX640
Technical Manual