GE 239 Instruction Manual

Also see for 239: Instruction manual

GE Multilin239 Motor Protection Relay8-38 TESTING 8 TESTING88.4 PHASE CURRENT OVERLOAD1. Alter the following setpoints:63527(&7,21?3+$6(&855(17?29(5/2$'?29(5/2$'&859(180%(566<67(06(783?&7,13876?3+$6(&735,0$5<$66<67(06(783?02725'$7$?02725)8///2$'&855(17$67(67,1*?7(67&21),*85$7,21?',6$%/(67$573527(&7,21<(62. Before beginning this test it is necessary to ensure that the thermal capacity value in $0(7(5,1*?02725&$3$&,7< is 0% to obtain a proper trip time. If required reset this value to 0% by short-ing together the Emergency Restart switch terminals (39, 44) momentarily. The EmergencyRestart input will not function if any phase or ground current is injected.3. Inject a current of 10 A into each phase in series. The relay will display a current value of:This represents four times 6 6<67(0 6(783?02725 '$7$?02725 )8// /2$' &855(17 setpoint.Therefore, based on a 400% overload and curve #4, the trip relay should activate after a time of23.3 seconds after the overload is first applied.4. After the overload trip has occurred, verify by viewing $0(7(5,1*?02725&$3$&,7< that the ther-mal capacity used is 98% to 100%. The thermal capacity value will start decreasing as soon asthe overload condition is removed and therefore may vary depending upon how quickly after theoverload trip the $ 0(7(5,1*?02725 &$3$&,7< message is viewed. After viewing$ 0(7(5,1*?02725 &$3$&,7<, momentarily short the Emergency Restart terminals and press thereset key to reset the unit.8.5 PHASE UNBALANCE ALARM1. Alter the following setpoints:63527(&7,21?3+$6(&855(17?81%$/$1&(?3+$6(81%$/$1&($/$502163527(&7,21?3+$6(&855(17?81%$/$1&(?3+$6(81%$/$1&(75,32))63527(&7,21?3+$6(&855(17?81%$/$1&(?3+$6(81%$/$1&($/$503,&.8363527(&7,21?3+$6(&855(17?81%$/$1&(?3+$6(81%$/$1&('(/$<6(&2. Connect the test set to inject current into phase A and phase C only. While viewing $0(7(5,1*?&855(17?&855(1781%$/$1&(8%, slowly increase the current until the UNBALANCE ALARMmessage comes on. Please note that the unbalance feature will not operate if the load is ≤ 30%FLC. In the table below, record the injected current level at the point when the unbalance alarmoccurred. Use the formulae shown below to calculate percent unbalance using the currentsrecorded in the table. Compare the calculated value to the displayed value on $0(7(5,1*?&855(17?&855(1781%$/$1&(8% and ensure they are match.displayed current actual injected current PHASE CT PRIMARY5 A-----------------------------------------------------------× 10 A 100 A5 A----------------× 200 A= = =