Xylem FLYGT P7030 Series - Stator Temperature Monitoring Methods

Table 7: 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 0–160 0ºC
(32–212ºF), see Pt100 resistance on
page 84.
> 200 ohm (approx.) can indicate the
following situations:
• Broken sensor
• Bad contact
• Broken lead
< 70 ohm (approx) indicates:
• Short circuit.
NOTICE:
Never connect the Pt100 transducer to a voltage higher than 2.5 V.
For information on the various configurations of switches, thermistors and sensors used to
monitor stator winding temperature, see
Stator temperature monitoring methods on page 16.
FLS
Table 8: Float switch sensor (FLS)
Description Measured value Fault values
The float switches are leakage
sensors.
Resistance. 2 sensor variants:
FLS:
• Normal: 1530 ohm
• Alarm: 330 ohm
FLS 10:
• Normal: 1200 ohm
• Alarm: 430 ohm
> 10% (approx.) deviation
from rated ohm values
indicates sensor fault, or fault
in the wiring.
VIS10
Table 9: Vibration sensor (VIS10)
Description Measured value Fault values
The vibration sensor located in
the junction box measures
vibrations in one direction. The
output is a 4-20 mA signal
proportional to the vibration
level.
Current, 4-20 mA • >> 20 mA indicates a short circuit.
• << 4 mA indicates a fault.
• A zero value indicates a broken wire or bad
contact in a connector.
3.6.3 Stator temperature monitoring methods
The purpose of stator-winding temperature monitoring is to make the motor shut off at high
temperature. There are two monitoring methods, depending on the types of thermal sensors
chosen.
Table 10: Stator temperature monitoring configuration
Configuration with thermal switches Configuration with thermistors
• Three thermal switches, connected in series, are
incorporated in the coil ends of the stator
winding. The switches are normally closed, and
open at 140°C (285°F).
• One Pt100 sensor is incorporated in one of the
windings.
• 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.
3 Product Description
P7030, P7035, P7040 Installation, Operation, and Maintenance Manual 19