Basler Electric BE1-51 - Manual (Page 59)

9137200997 Rev G 53
Time Overcurrent Characteristic Curves
Graphs on the following pages illustrate sample characteristic curves for all of the time overcurrent
functions individually as options, or selectable by switch (if the Z1, Z2, or Z3 timing option is specified). Z1
option can select any of the timing types designated as B1 through B8, and C1 through C8. Z2 option can
select any of the timing types designated as B1 through B8, and the British Standard timing types: E2,
E4, E5, E6, and E7. Z3 option can select the integrating algorithm for any of the timing types designated
as B1 through B8, and C1 through C8.
Note that there are two versions of each timing type: standard and extended timing. Both types are
located on the same page. The exception to this is the British Standard curves, which do not have an
extended timing version. For any given relay, either the standard or the extended range version will apply,
never both.
Table 5 lists timing choices with available curves. Table 6 lists the positions of the timing curve selector
switch. (See the Controls and Indicators chapter for switch location).
Table 5. Timing Choices with Available Curves
Timing Choices Z1 Z2 Z3 (Integrating)
Available Curves
Short Inverse Short Inverse Short Inverse
Long Inverse Long Inverse Long Inverse
Definite Time Definite Time Definite Time
Moderately Inverse Moderately Inverse Moderately Inverse
Inverse Time Inverse Time Inverse Time
Very Inverse Very Inverse Very Inverse
Extremely Inverse Extremely Inverse Extremely Inverse
I 2 t BS 142 Long Inverse I 2 t
I 2 t with Limit 1 BS142 Inverse I 2 t with Limit 1
I 2 t with Limit 2 BS142 Inverse I 2 t with Limit 2
I 2 t with Limit 3 BS142 Very Inverse I 2 t with Limit 3
I 2 t with Limit 4 BS142 Extremely Inverse I 2 t with Limit 4
I 2 t with Limit 5 N/A I 2 t with Limit 5
I 2 t with Limit 6 N/A I 2 t with Limit 6
I 2 t with Limit 7 N/A I 2 t with Limit 7
I 2 t with Limit 8 N/A I 2 t with Limit 8
BE1-51 Time Overcurrent Characteristic Curves