DEMA CPM 310 G User Manual page 209

Technical Characteristics
2 Protection Functions
2.1 Phase Overcurrent Protection [ANSI 50/51]
Measurement Technique
Current Measurement Range
Current Threshold Setting Range
Pick-up Current
Current Reset Ratio (Hysteresis)
Instantaneous Trip Time
Drop-out Time
Trip Time Delays for Phase Thresholds
Inverse Protection Curves available
Reset Time Delays for Phase Thresholds Below descriptions are valid for tI>, tI>>, tI>>>.
2.2 Earth Overcurrent Protection [ANSI 50N/51N]
Measurement Technique
Current Measurement Range
Current Threshold Setting Range
Fundamental harmonic.
(0.1-40) I
n
Important Note: It must be kept in mind that CPM 310 measures currents up to 40
In, and no precise evaluations can be done for current values higher than this.
3 independent thresholds, set as multipliers of In.
1.threshold and set interval : (0.1-25) I
2.threshold and set interval : (0.5-40) I
3.threshold and set interval : (0.5-40) I
For all threshold values: over 1.05 times the set value.
~%95
~35 ms
~40 ms
Below descriptions are valid for tI>, tI>>, tI>>>.
DMT, Definite Minimum Time.
Setting Range: (0.01-150) s, step: 0.01 s.
IDMT, Inverse Definite Minimum Time.
Setting Range: TMS (Time Multiplier Setting): (0.025-3.2), step: 0.001.
IEC STI, IEC Short Time Inverse
IEC SI, IEC Standard Inverse
IEC VI, IEC Very Inverse
IEC EI, IEC Extreme Inverse
IEC LTI, IEC Long Time Inverse
SA, Semiconductor Protection
SB, Definite Inverse
SC (CO2), Short Time Inverse
SD (CO8), Long Time Inverse
SE (CO-C3H), Normal Inverse
IEEE MI, IEEE Moderately Inverse
IEEE VI, IEEE Very Inverse
IEEE EI, IEEE Extremely Inverse
DMT, Definite Minimum Time.
Setting Range: (0.01-150) s, step: 0.01 s.
IDMT, Inverse Definite Minimum Time.
Setting Range: TMS (Time Multiplier Setting): (0.025-3.2), step: 0.001.
Fundamental harmonic.
For Type T1 Protection: (0.1-40) I
For Type T2 Protection: (0.02-5) I
3 independent thresholds, set as multipliers of Ien.
Setting range for type T1: (0.1 - 40) Ien.
For T1 Ie> : (0.1 - 25) Ien, in 0.01 Ien steps.
For T1 Ie>> : (0.5 - 40) Ien, 0.01 Ien steps.
For T1 Ie>>> : (0.5 - 40) Ien, 0.01 Ien steps.
Setting range for type T2: (0.02 - 5) Ien.
For T2 Ie> : (0.02 - 5) Ien, 0.001 Ien steps.
For T2 Ie>> : (0.02 - 5) Ien, 0.001 Ien steps.
For T2 Ie>>> : (0.02 - 5) Ien, 0.001 Ien steps.
- 209 -
, in 0.01 I steps.
n n
, in 0.01 I steps.
n n
, in 0.01 I steps.
n n
, in 0.01 I steps.
en en
, in 0.001 I steps.
en en