Basler BE1-50/51B-217, Instruction Manual, Page: 12 / 49

BE1-50/51B-217 General Information
1-7
Figure 1-5. Instantaneous Characteristic Curves
Time Characteristics Nine inverse time functions and one fixed time function can be selected
by a front panel switch.
Time Reset Reset occurs when the current drops below pickup and the relay has not
timed out. Switch SW8-4 provides selection of either an instantaneous
or integrating reset characteristic. Opening SW8-4 forces the
instantaneous reset timer to zero when timed dropout occurs. This fast
reset characteristic prevents the ratcheting effect that may occur with
repeating system faults. Closing SW8-4 selects the integrating reset
characteristic. The integrating reset characteristic simulates the disk
reset of electromechanical relays. BE1-50/51B-217 relays provide the
integrating reset function even when input current falls to zero.
Integrating reset characteristics are shown in Figure 1-6.
Target Indicators Magnetically latched, manually reset targets indicate that current of 0.2
amperes or greater was present in the trip circuit. Target coil resistance
is less than 0.1 ohm and operate time is less than one millisecond.
See 50/51 Output specifications for maximum current rating.