32
Basic Function Details Section 2-4
Current Tripping Characteristics
■ Standard Detection
■ Instantaneous Detection
■ Extended Detection
Note The S8AS contains a current-restricting circuit that prevents a cur-
rent above a specific value from flowing. The current is thus restrict-
ed during the time required to cut off the output.
Note After sampling and converting each branch output's current every 1 ms, the
S8AS processes the values in the CPU and controls the branch output cut-
offs. This method achieves high-speed, high-accuracy tripping. In addition, to
minimize the effects of excessive currents caused by short-circuits, the S8AS
is equipped with built-in current-limiting circuits. Consequently, there is a
Setting
range
Tripping region
Current-
limiting
by internal
circuits
Current (A)
100
Time (ms)
60
20
0.5
3.8 11
16 19
Tolerance of current trip-
ping alarm threshold:
±0.3 A. When the trip-
ping current (0.5 to
3.8 A) is detected, it is
cut off within 100 ms.
20
0.5
3.8
19
Setting
range
Tripping region
Current-
limiting
by internal
circuits
Current (A)
Time (ms)
Tolerance of current trip-
ping alarm threshold:
±0.3 A. When the trip-
ping current (0.5 to
3.8 A) is detected, it is
cut off within 20 ms.
20
0.5
3.8
19
60
1,000
11
16
Setting
range
Tripping region
Current-
limiting
by internal
circuits
Current (A)
Time (ms)
Tolerance of current trip-
ping alarm threshold:
±0.3 A.When the trip-
ping current (0.5 to
3.8 A) is detected, it is
cut off within 1,000 ms.