Motor Bearings; Inspection Checklist; Disassemble And Replace The Pump Parts; Troubleshooting For Users - Xylem Goulds NSC Manual De Instalación, Funcionamento Y Mantenimiento

en - Original instructions
Contact the local sales and service representative
for any requests or information.

Motor bearings

After approximately five years, the grease in the mo-
tor bearings is so aged that a replacement of the
bearings is recommended. The bearings must be re-
placed after 25000 operating hours or according to
the motor supplier maintenance instructions, which-
ever is shorter.
Motor with regreasable bearings
Follow motor supplier maintenance instructions.
Coupling
Check the clearance in the coupling elements regu-
larly, at least once a year. We recommend checking
every 1000 operating hours or every three months,
whichever comes first.

6.2 Inspection checklist

Check the coupling
Check the mechanical
seal
Checking the bearing
seals
Check for quiet running
6.3 Disassemble and replace the pump
parts
For more information about spare parts and assem-
bly and disassembly of the pump, contact the local
sales and service representative.
7 Troubleshooting

7.1 Troubleshooting for users

The main switch is on, but the electric pump
does not start.
Cause
The thermal protector
incorporated in the
pump (if any) has trip-
ped.
The protective device
against dry running has
tripped.
The electric pump starts, but the thermal protection
trips a varying time after.
24
Check the flexible ele-
ments of the coupling.
Replace the relevant
parts if there is any sign
of wear and check the
alignment.
Check for leakage of the
mechanical seal. Re-
place the mechanical
seal if leakage is found.
Check correct seating of
axial seal rings mounted
on the shaft. Only gentle
contact of the sealing lip
shall be established.
Check frequently for qui-
et running of the pump
with vibration measure-
ments tools.
Remedy
Wait until the pump has
cooled down. The thermal
protector will automatical-
ly reset.
Check the liquid level in
the tank, or the mains
pressure.
Cause
There are foreign objects
(solids or fibrous sub-
stances) inside the pump
which have jammed the
impeller.
The pump is overloaded
because it is pumping liq-
uid that is too dense and
viscous.
The pump runs but delivers too little or no liquid.
Cause Remedy
The pump is clog- Contact the Sales and Service
ged. Department.
The troubleshooting instructions in the tables below
are for installers only.
7.2 The main switch is on, but the
electric pump does not start
Cause
There is no power
supply.
The thermal protector
incorporated in the
pump (if any) has trip-
ped.
The thermal relay or
motor protector in the
electric control panel
has tripped.
The protective device
against dry running
has tripped.
The fuses for the
pump or auxiliary cir-
cuits are blown.
7.3 The electric pump starts, but
the thermal protector trips or the
fuses blow immediately after
Cause
The power supply ca-
ble is damaged.
The thermal protection
or fuses are not suited
for the motor current.
Remedy
Contact the Sales and
Service Department.
Check the actual power
requirements based on
the characteristics of the
pumped liquid and then
contact the Sales and
Service Department.
Remedy
• Restore the power sup-
ply.
• Make sure all electrical
connections to the pow-
er supply are intact.
Wait until the pump has
cooled down. The thermal
protector will automatically
reset.
Reset the thermal protec-
tion.
Check the:
• liquid level in the tank,
or the mains pressure.
• protective device and its
connecting cables.
Replace the fuses.
Remedy
Check the cable and re-
place as necessary.
Check the components
and replace as necessary.