Teral NSVM 25 Series, Installation & Operating Manual

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NSVM, NSVMN
7
Fault Probable cause Possible Solution
a. Leakage in the foot valve, check valve or system. Repair or replace the components. The frequency of
Pump start-up is
too high.
b. Ruptured membrane or no air pre-charge in surge tank. See relevant instructions in surge tank’s manual.
a. Cavitation
Reduce the required flow or improve the operating
conditions of the pump (suction conditions, head, flow
resistance, liquid temperature, viscosity,…etc.).
b. Make sure that pump and motor shafts are properly aligned Adjust the pump and/or motor shafts.
c . Worn motor bearings Replace the bearings or the motor.
d. Operation with frequency converter
Consult a qualified engineer form the supplier of the
frequency converter.
Vibration and
noise
e. Check vibration and noise damping devices Replace vibration & noise dampers, if worn.
Maximum Operating Pressure and inlet Pressure