Laserfiche WebLink
7 Troubleshooting <br />.7.4 The pump starts -stops -starts in rapid sequence <br />Cause <br />Remedy <br />The pump starts due to back -flow <br />Check that: <br />which fills the sump to the start level <br />. The distance between the start and stop levels is sufficient. <br />again. <br />• The non -return valve(s) work(s) properly. <br />• The length of the discharge pipe between the pump and the first non - <br />return valve is sufficiently short. <br />The self -holding function of the <br />Check: <br />contactor malfunctions. <br />• The contactor connections. <br />• The voltage in the control circuit in relation to the rated voltages on the <br />coil. <br />• The functioning of the stop -level regulator. <br />• Whetherthe voltage drop in the line atthe starting surge causes the <br />contactor'sself-holding malfunction. <br />If the problem persists, then contact a sales or authorized service representative. <br />Always state the serial number of the product, see Product Description on page 11. <br />7.5 The pump runs but the motor protection trips <br />DANGER: Crush Hazard <br />Moving parts can entangle or crush. Always disconnect and lock out power before <br />! servicing to prevent unexpected startup. Failure to do so could result in death or serious <br />injury. <br />t <br />WARNING: Electrical Hazard <br />The permanent -magnet motor generates voltage when the shaft rotates, even if power <br />sources are disconnected. Never perform any electrical work if the shaft could rotate. <br />NOTICE: <br />Do NOT override the motor protection repeatedly if it has tripped. Doing so may result in <br />equipment damage. <br />Cause <br />Remedy <br />The motor protection is set too low. <br />Set the motor protection according to the data plate and'if applicable the <br />cable chart. <br />The impeller is difficultto rotate by <br />• Clean the impeller. <br />hand. <br />• Clean out the sump. <br />• Check that the impeller is properly trimmed. <br />The drive unit is not receiving full <br />• Check the fuses. Replace fuses that have tripped. <br />voltage on all three phases. <br />• If the fuses are intact, then notify a certified electrician. <br />The phase currents vary, or they are <br />Contact a sales or authorized service representative. <br />too high. <br />Flygt 3102 Installation, Operation, and Maintenance Manual 67 <br />