Basler BE1-50/51B-217, Instruction Manual

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BE1-50/51B-217 General Information
1-6
Harmonic Response BE1-50/51B harmonic rejection is illustrated in Figure 1-4.
Figure 1-4 shows that a relay set for one ampere pickup would pickup at
0.96 ampere on a current containing 40% seventh harmonic. This
corresponds to a ten-to-one rejection ratio. Other conditions may be
evaluated in the same manner.
Figure 1-4. Harmonic Response
INST Characteristics BE1-50/51B instantaneous characteristic curves are similar to standard
electromechanical instantaneous units. However, the time to trip for
ground applications is slightly longer than that for phase applications to
allow time to power-up the relay. Longer trip time for ground
applications is beneficial because it helps to avoid nuisance trips.
For phase applications, the maximum time to trip is 3.5 cycles at a
pickup multiple of 1.0, and 1.5 cycles at a pickup multiple of 3.0. The
corresponding times for ground applications are 4.5 and 1.75 cycles.
Figure 1-5 shows the instantaneous characteristic curves for maximum
time to trip.
Additional delays of 0.1, 0.2, or 0.3 seconds may be added with internal
switches SW8-2 and -3. These delays apply to both phase and ground
applications. Closing switch SW8-2 provides an additional delay of 0.1
second. Closing switch SW8-3 provides an additional delay of 0.2
second. Closing both switches SW8-2 and -3 provides an additional
delay of 0.3 second. Section 2 illustrates the location of SW8.