4.1.1.11 Technical data
Table 231: 51P, 50P, 50P-3 Technical data
Characteristic
Value
Operation accuracy Depending on the frequency of the measured
current: f
n
±2 Hz
51P
±1.5% of the set value or ±0.002 × I
n
50P
and
50P-3
±1.5% of set value or ±0.002 × I
n
(at currents in the range of 0.1…10 × I
n
)
±5.0% of the set value
(at currents in the range of 10…40 × I
n
)
Pickup time
1)2)
Minimum Typical Maximum
50P-3:
I
Fault
= 2 × set
Pickup
value
I
Fault
= 10 × set
Pickup
value
16 ms
11 ms
19 ms
12 ms
23 ms
14 ms
50P and 51P:
I
Fault
= 2 × set
Pickup
value
23 ms
26 ms
29 ms
Reset time
Typically 40 ms
Reset ratio Typically 0.96
Retardation time <30 ms
Trip time accuracy in definite time mode ±1.0% of the set value or ±20 ms
Trip time accuracy in inverse time mode
±5.0% of the theoretical value or ±20 ms
3)
Suppression of harmonics RMS: No suppression
DFT: -50 dB at f = n × f
n
, where n = 2, 3, 4, 5,…
Peak-to-Peak: No suppression
P-to-P+backup: No suppression
1)
Measurement mode
= default (depends on stage), current before fault = 0.0 × I
n
, f
n
= 50 Hz, fault current in
one phase with nominal frequency injected from random phase angle, results based on statistical
distribution of 1000 measurements
2) Includes the delay of the signal output contact
3) Maximum
Pickup value
= 2.5 × I
n
,
Pickup value
multiples in range of 1.5...20
Section 4 1MAC059074-MB A
Protection functions
230 615 series ANSI
Technical Manual