Submersible Motor Performance Guidelines For Use On Variable Frequency Drives - Xylem CentriPro FM Serie Manual De Instrucciones

Submersible Motor Performance Guidelines For Use On Variable Frequency Drives

IV. Submersible Motor Performance
Guidelines For Use On Variable
Frequency Drives
The CentriPro motor has been used extensively with variable frequency drives. As with any modified
application, there are considerations to evaluate when using an inverter, or Variable Frequency
Drive (VFD), to operate a submersible motor. To ensure reliable operation, the following guidelines
must be followed when using the 2 pole CentriPro submersible motor with a VFD.
1. Proper, class 10, quick trip, overload protection must be used at all times. As a minimum,
Overloads must trip at five times full load current within 10 seconds on any phase.
2. A minimum of 1.5 times full load current should be available to initially start the motor if needed.
3. Minimum operating frequency is 30 hertz
4. Minimum Speed: 0.5 x Synchronous Speed (Example: 3600 RPM x .5 = 1800 RPM)
5. Maximum Speed: 1.00 x Full Load Speed
6. Ramp-up Time: Maximum 1 second to reach 30 Hz, maximum 4.0 seconds to reach current limit
and rated speed
7. Ramp down time: from minimum frequency to power shutoff shall be four (4) seconds.
8. At the minimum speed (see #3), one-half foot per second water velocity, at rated temperature,
must be maintained past the motor. Velocity in excess of 10 feet per second is not recommended.
9. The VFD must maintain a constant volts to Hertz ratio. The controls must be rated the same as
motor nameplate.
10. The output of the VFD must have a filtering or line conditioning device installed to eliminate
voltage waveform phenomenon that might adversely affect motor components and elements.
Power at the motor leads must be clean, free of high voltage transients, harmonics, and within
the voltage range of the motor (1000V peak at more than .2 microsecond rise time).
11. All other requirements and restrictions for the CentriPro submersible motor apply.
These are general guidelines for the operation of the 2 pole CentriPro submersible motor on
AC Inverters incorporating IGBT type switching devices and starting from zero rotation with a
limited, immediate, hydraulic load.
6 FM Series Motors Installation, Operation and Maintenance Manual