Checking Insulation And Sensors; Check The Insulation, Up To 1 Kv Drives Or Generators; Check The Temperature Sensors - Xylem FLYFT P7900 Installation, Operation And Maintenance Manual

After any service involving the power connections, check the rotation before operating the
pump. See

6.2.3 Checking insulation and sensors

It is important that the checks for motor insulation, temperature sensors and leakages
sensors are performed correctly and using appropriate tools. Parts of the unit, for example
temperature sensors or the PEM, can be damaged if a megger or other device is used to
apply a voltage higher than 2.5 V.
Use the following table to choose the appropriate procedures.
Item
Motor insulation, drive units or generators up to 1
kV
Thermal contacts
PTC thermistors
Pt100
FLS leakage detector

6.3 Check the insulation, up to 1 kV drives or generators

1. Check that the resistance between earth and phase lead is more than 5 MΩ.
Use a 500 VDC or 1000 VDC megger.
2. Keep a record of the results.

6.4 Check the temperature sensors

If the unit is connected to the MAS monitoring system, then it is recommended that the
sensors be checked in the MAS unit. Otherwise, use a multimeter.
P7900 Installation, Operation, and Maintenance Manual
Part to service Action
Sensors Check the following:
1. Stator temperature sensors
2. Bearing temperature sensors
3. FLS and CLS sensors
Check the temperature sensors
See
detectors
Impeller or propeller Check the general impeller or propeller status. Change if necessary.
Check general wear ring status. Change if necessary.
Zinc anodes Check their condition. Replace if necessary.
Screw joints Check all externally accessible screw joints and tighten if necessary to the
correct torque. See torque table and Parts List.
Lifting handle Check its condition. Replace if necessary.
Painting Touch up any painting if necessary.
Rotational direction Check the impeller or propeller rotation direction. See
rotation
Voltage and Check the running values.
amperage
Electrical cabinets or Check that it is clean and dry.
panels
Connection to power Check the cable connections. Tighten if necessary.
Overload protection Check the correct settings.
and other protections
Level regulators Check condition and function.
Check the impeller rotation
on page 52.
on page 42.
on page 42.
Section
Check the insulation, up to 1 kV drives or
generators
Check the temperature sensors
Check the leakage detectors
6 Maintenance
Check the leakage
on page 51 and
Check the impeller
on page 51
on page 51
on page 52
51