SEPAM Trip Curves: Type 1 versus Type 1.2

Issue

User would like to understand the difference in tripping characteristics between Type 1 and Type 1.2 trip curves on SEPAM relays.

Product

SEPAM Series 20
SEPAM Series 40
SEPAM Series 80

Environment

SFT2841 configuration software

Cause

Confusion arises due to the availability of two curve types (Type 1 and Type 1.2) that appear similar but have different pickup conditions, which affects protection coordination and relay response.

Resolution

SEPAM relays offer two selectable trip curve types: Type 1 and Type 1.2.

• Type 1 Curve:
• Pickup occurs when the measured current equals the relay threshold setting
• Condition: I = Is
• Type 1.2 Curve:
• Pickup occurs when the measured current reaches 1.2 times the relay threshold setting
• Condition: I = 1.2 × Is
• After pickup, it follows the same tripping characteristics as the standard Type 1 (IEC) curve

Key difference:

• The only distinction between the two curves is the pickup level
• Once pickup is reached, both curves behave identically in terms of time-current characteristics

For further analysis and visualization:

• Refer to the available trip curve calculators for SEPAM and MiCOM relays
• Review the comparison charts showing Type 1 vs Type 1.2 characteristics

Julkaistu: Schneider Electric Suomi