Custom Protection Curves - DEMA CPM 310 G User Manual

Custom Protection Curves

CPM 310 G Special Curves include inverse protection curves for electromechanical relays, constant
time characteristic and reset curves. These curves are listed below.
1. SA Semic: Semiconductor Protection Curve.
2. SB DI: Definite Inverse Curve.
3. SC CO2: Short time Inverse Curve.
4. SD CO8: Long Time Inverse Curve.
5. SE CO-C3H: Standard Inverse Curve.
Universal trip time delay formula is given above, while special curve parameters are given on the
below table.
t Trip delay (s).
A A constant for the characteristic (s).
I Momentary current (A).
Is Set current threshold (A).
α A constant for the characteristic (-).
B A constant for the characteristic (s).
TMS Time Multiplier Setting (-). □
Curve Type
SA Semic
Semiconductor Protection
SB DI
Definite Inverse
SC CO2
Short Time Inverse
SD CO8
Long Time Inverse
SE CO-C3H
Standard Inverse
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