LSB german_french_english 771076129 - Water Solutions

Installation, Operation and Maintenance InstructionModel LSB10. Faults - Causes and SolutionsThe following notes on causes of faults and how torepair them are intended as an aid to recognising theproblem. The manufacturer's Customer ServiceDepartment is available to help repair faults that theoperator cannot or does not want to repair. If theoperator repairs or changes the pump, the design dataon the data sheet and chapter 2 of these OperatingInstructions should be particularly taken into account.If necessary, the written agreement of themanufacturer must be obtained.Discharge too lowDischarge stops after a timeHead too lowHead too highDrive mechanism overloadedPump not running quietlyTemperature in pump too highTemperature in shaft sealing too highTemperature at the bearing too highPump leakingLeakage rate at shaft sealing too highCause■ Back-pressure too high check facility for pollution, open discharge valvereduce resistance in discharge pipe (e.g. clean filter ifnecessary)use larger impeller (note available motor power)■ ■ ■ Back-pressure too low, discharge too low throttle discharge valve■ ■ Speed too high reduce speedcompare speed of motor with specified pump speed (ratingplate)when adjusting speed (frequency transformer) check referencevalue setting■ ■ Speed too low increase speed (check available motor power)compare speed of motor with specified pump speed (ratingplate)when adjusting speed (frequency transformer) check referencevalue settings■ ■ ■ ■ Flow too little increase min. flow (open discharge valve, bypass)■ Flow too big reduce flow (throttle discharge valve)■ ■ Impeller diameter too big use smaller impeller■ ■ Impeller diameter too small use larger impeller (check available motor power)■ ■ ■ ■ Pump and/or pipes not completely filled with liquid fillvent■ ■ ■ Pump or suction/intake pipe blocked clean■ ■ Air pocket in pipeline ventimprove course of pipe■ ■ ■ ■ ■ Suction height too big / NPSH of system too small increase liquid level and admission pressurereduce resistance in the intake/suction pipe (change courseand rated width, open shut-off valves, clean filters)■ ■ ■ Air being sucked in increase liquid levelcheck if suction pipe is vacuum-tight■ ■ ■ Air being sucked in through shaft sealing clean sealing pipeincrease sealing pressurereplace shaft sealing■ ■ Direction of rotation is wrong swap over two phases of power supply (to be done by anelectrician)■ ■ ■ ■ Inner components suffering from wear replace worn parts■ ■ ■ Density and/or viscosity of liquid handled is too high seek assistance■ ■ Lines and roughness at shaft replace parts■ ■ Deposits on mechanical seal cleanreplace mechanical seal if necessaryif necessary provide additional rinsing or quench■ ■ Impeller out of balance remove blocks/depositsreplace impeller if broken or unevenly worncheck shafts to ensure that they are running true■ ■ ■ ■ ■ Forces in pipeline too high (pump unit under strain) change (support pipes, use compensators, etc.)is foundation plate/frame properly cast in place?■ Electricity supply not right (2-phase running) check voltage of all phasescheck cable connections and fuses■ Sealing insufficient tighten screwsreplace sealing■ ■ Bearing damaged replace■ Relief fittings insufficient clean relief openings in impellerreplace worn parts (impeller, split rings)adjust in line with the system pressure/intake pressure given onordering■ System-related vibrations (resonance) seek assistanceSolutionLSB 100-english page 87 Revision 02Artikel Nr. 771076129 Ausgabe 01/2010