The Pump Runs But The Motor Protection Trips - Xylem FLYFT P7900 Installation, Operation And Maintenance Manual

7 Troubleshooting
Always state the serial number of the product, see

7.5 The pump runs but the motor protection trips

DANGER: Crush Hazard
Moving parts can entangle or crush. Always disconnect and lock out power before servicing
to prevent unexpected startup. Failure to do so could result in death or serious injury.
NOTICE:
Do NOT override the motor protection repeatedly if it has tripped. Doing so may result in
equipment damage.
Cause
The motor protection is set too
low.
The impeller is difficult to rotate
by hand.
The drive unit is not receiving full
voltage on all three phases.
The phase currents vary, or they
are too high.
The insulation between the
phases and ground in the stator is
defective.
The density of the pumped fluid is
too high.
There is a malfunction in the
overload protection.
Always state the serial number of the product, see
70
Product Description
Remedy
Set the motor protection according to the data plate and if applicable
the cable chart.
• Clean the impeller.
• Clean out the sump.
• Check that the impeller is properly trimmed.
• Check the fuses. Replace fuses that have tripped.
• If the fuses are intact, then notify a certified electrician.
Contact a sales or authorized service representative.
See Check the insulation, up to 1 kV drives or generators
51.
Make sure that the maximum density is 1100 kg/m3 (9.2 lb/US gal)
• Change the impeller, or
• Change to a more suitable pump
• Contact a sales or authorized service representative.
Replace the overload protection.
Product Description
P7900 Installation, Operation, and Maintenance Manual
on page 10.
on page
on page 10.