Xylem LOWARA e-SHE Series - Frequency Converter Operation Guidance

en – Original Instructions
e-SHE, e-SHS
– Additional Installation, Operation and Maintenance Instructions 25
4.4.5 Operation with frequency converter
The three-phase motors can be connected to a frequency converter for speed control.
• The converter exposes the insulation of the motor to a greater load, determined by the
length of the connecting cable: observe the requirements of the Manufacturer of the
frequency converter
• For applications requiring silent operation, install an outlet filter between the motor and the
converter; a sinusoidal filter can reduce the noise even further
• The bearings of the motors, from size 315 S/M and up, are exposed to the risk of harmful
currents: use electrically insulated bearings
• The conditions of installation must guarantee protection against voltage peaks between the
terminals and/or dV/dt in the table:
Motor size
Voltage peak, V
dV/dt, V/µs
up to 90R (500 V)
< 650
< 2200
from 90R to 180R
< 1400
< 4600
over 180R
< 1600
< 5200
Otherwise, use a motor with reinforced insulation
1
and a sinusoidal filter.
1
Available on request