Autoreclose (Ansi 79) - GE C60 Instruction Manual

CHAPTER 5: SETTINGS
I is the measured overload RMS current at index n
n
E is the accumulated energy at index n
n
E is the accumulated energy at index n – 1
n – 1
The thermal overload protection element removes the
emergency, the thermal memory and
All calculations are performed per phase. If the accumulated energy reaches value 1 in any phase, the thermal overload
protection element operates and only resets when energy is less than 0.05 in all three phases.
Table 5-36: Typical time constants
Protected equipment
Capacitor bank
Overhead line
Air-core reactor
Busbar
Underground cable
The figure shows the logic for the thermal overload protection element.

5.8.11 Autoreclose (ANSI 79)

SETTINGS  CONTROL ELEMENTS  AUTORECLOSE  AUTORECLOSE
 AUTORECLOSE

C60 BREAKER PROTECTION SYSTEM – INSTRUCTION MANUAL
THERMAL PROT 1 OP
output operand can be reset using
THERMAL PROT 1 OP
Time constant Minimum reset time
10 minutes 30 minutes
10 minutes 20 minutes
40 minutes 30 minutes
60 minutes 20 minutes
20 to 60 minutes 60 minutes
Figure 5-149: Thermal overload protection logic
AR FUNCTION:

Disabled
AR MODE:

Mode 1 (1 & 3 Pole)
Mode 1 Activation:

Off
Mode 2 Activation:

Off
output operand when E < 0.05. In case of
THERM PROT 1 RESET
Range: Disabled, Enabled
Range: Mode 1(1 & 3 Pole), Mode 2 (1 Pole), Mode 3 (3
Pole-A), Mode 4 (3 Pole-B)
Range: FlexLogic operand
Range: FlexLogic operand
CONTROL ELEMENTS
setting.
5
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