Xylem FLYFT P7900, Installation, Operation And Maintenance Manual

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monitoring the stator winding temperature depend upon the voltage range of the drive unit.
See
Drive units
on page 10 for the voltage range for each drive unit.
Up to 1 kV drive units
Table 6: Stator temperature monitoring configuration, up to 1 kV
Standard / Optional Monitoring configuration description
Standard
• Three thermal contacts, which are connected in series, are incorporated in the
coil ends of the stator winding. The contacts are normally closed, and open at
140°C (285°F).
• One Pt100 sensor is incorporated in one of the windings.
Or:
• Three thermistors, PTC, connected in series, are incorporated in the coil ends
of the stator windings. T
Ref
=140°C (285°F).
• One Pt100 sensor is incorporated in one of the windings.
Optional • Three thermal contacts, which are connected in series, are incorporated in the
coil ends of the stator winding. The contacts are normally closed, and open at
140°C (285°F).
• Three Pt100 sensors, one for each phase, are incorporated in the windings.
Or:
• Three thermistors, PTC, connected in series, are incorporated in the coil ends
of the stator windings. T
Ref
=140°C (285°F)
• Three Pt100 sensors, one for each phase, are incorporated in the windings.
3.5.4.1 Temperature sensors
Table 7: Thermal contact
Description Measured value Fault values
The thermal
contact is a
normally closed
contact.
0–3 ohm, unless the wires are long. An infinite value (open circuit) indicates
either high temperature or a fault.
Examples of faults include a broken wire,
or a bad contact in a connector.
Table 8: PTC thermistor
Description Measured value Fault values
The PTC
thermistor is a
semiconductor
device.
Resistance at normal temperature:
• 50–100 ohm (150–300 ohm for three in
series).
• Above the tripping point, T
Ref
, the
resistance increases dramatically to
several kilohm.
• An infinite value (open circuit)
indicates a fault. Examples of faults
include a broken wire, or a bad
contact in a connector.
• A value close to zero indicates a short
circuit in the wiring.
Table 9: Pt100 sensor
Description Measured value Fault values
The Pt100 sensor
is a resistor
changing value
almost linearly with
temperature.
Resistance:
• 100 ohm at 0ºC (32ºF)
• 107.79 ohm at room temperature
(20ºC, 68ºF)
• 138.5 ohm at 100ºC (212ºF)
For resistance data between 0–160ºC
(32–320ºF), see
Pt100 resistance
on
page 71.
> 200 ohm (approximate) can indicate
the following situations:
• Broken sensor
• Bad contact
• Broken lead
< 70 ohm (approximate) indicates:
• Short circuit
3 Product Description
16 P7900 Installation, Operation, and Maintenance Manual