LV generator protection - engineering site - Schneider Electric
LV generator protection - engineering site - Schneider Electric
LV generator protection - engineering site - Schneider Electric
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STR23SE (U y 525 V) and STR23SV (U > 525 V)electronic trip unitsE887346 1 73test+-.7.63.5Io.8 .91x InSTR 23 SEIr.9 .93.88 .95.85 .98.8 1x Ioalarm43290105 %IrIsd5 6x Ir7810IrIsdE88735t123450 Ir Im1 long-time threshold (overload <strong>protection</strong>)2 long-time tripping delay3 short-time pick-up (short-circuit <strong>protection</strong>)4 short-time tripping delay5 instantaneous pick-up (short-circuit <strong>protection</strong>)6 test connector7 percent load indication.ProtectionIThe <strong>protection</strong> functions may be set using the adjustment dials.Overload <strong>protection</strong>Long-time <strong>protection</strong> with an adjustable threshold and fixed tripping delay:b Io base setting (6-position dial from 0.5 to 1)b Ir fine adjustment (8-position dial from 0.8 to 1).Short-circuit <strong>protection</strong>Short-time and instantaneous <strong>protection</strong>:b short-time <strong>protection</strong> with an adjustable pick-up and fixed tripping delayb instantaneous <strong>protection</strong> with fixed pick-up.Protection of the fourth poleOn four-pole circuit breakers, neutral <strong>protection</strong> is set using a three-positionswitch to 4P 3d (neutral unprotected), 4P 3d + N/2 (neutral <strong>protection</strong> at 0.5 In) or4P 4d (neutral <strong>protection</strong> at In).IndicationsA LED on the front indicates the percent load:b ON - load is > 90 % of Ir settingb flashing - load is > 105 % of Ir setting.TestA mini test kit or a portable test kit may be connected to the test connector on thefront to check circuit-breaker operation after installing the trip unit or accessories.53