Use Of Dv/Dt Filter; Motor With Enameled Round Wire; Motor With Prewound Coils; Bearing Insulation - WEG W22 Premium E3 Manual De Instalación, Operación Y Mantenimiento

If the motor is operated above the rated frequency, please note:
That the motor must be operated at constant output;
g
That the motor can supply max. 95% of its rated output;
g
Do not exceed the maximum speed and please consider:
g
max. operating frequency informed on the additional nameplate;
g
mechanical speed limitation of the motor.
g
The "Ex n" motor line driven by frequency inverter (used in Zone 2 – presence of gas) can be operated up to the
limit of the Temperature Class T3 (200 °C).
The "Ex t" motor line driven by frequency inverter (used in Zone 22 and Zone 21 - in the presence of
combustible dust) can be operated up to the temperature limit of 125 °C.
Information on the selection of the power cables between the frequency inverter and the motor can be found in
the item 6.8 of the "Technical Guidelines for Induction Motors driven by PWM Frequency inverters" available at
www.weg.net.

6.14.1. Use of dV/dt filter

6.14.1.1. Motor with enameled round wire

Motors designed for rated voltages up to 690 V, when driven by frequency inverter, do not require the use of
dV/dT filters, provided that following criteria are considered.
Criteria for the selection of motors with round enameled wire when driven by frequency inverter
Peak voltage at the
Motor rated votage 2
motor terminals (max)
Vnom ≤ 460 V
460 < Vnom ≤ 575 V
575 < Vnom ≤ 690 V 4
575 < Vnom ≤ 690 V 5
Notes:
1. For the application of motors with round enameled wires designed for 690 < Vnom ≤ 1100 V, please contact WEG.
2. For the application of dual voltage motors, example 380/660 V, consider the lower voltage (380 V).
3. Information supplied by the inverter manufacturer.
4. When not stated in the Purchase Order that the motor will be driven by frequency inverter.
5. When stated in the Purchase Order that the motor will be driven by frequency inverter.

6.14.1.2. Motor with prewound coils

Motors with prewound coils (medium and high voltage motors regardless of frame sizes, and low voltage
motors from IEC 500 / NEMA 800 frame on), designed for the use with frequency inverters, do not require the
use of filters, provided they comply with the criteria in Table 6.10.
Table 6.10 - Criteria to be considered when using motor with prewound coils to be drive by frequency inverters
Motor rated voltage
modulation
Sinusoidal
690 < Vnom ≤ 4160 V
Sinusoidal
4160 < Vnom ≤ 6600 V

6.14.2. Bearing insulation

Only the motors in IEC frame size 400 (NEMA 680) and larger are supplied, as standard, with insulated bearing.
If motor must be driven by frequency inverter, insulate the bearing according to Table 6.11.
inverter output (max)
≤ 1600 V ≤ 5200 V/µs
≤ 1800 V ≤ 6500 V/µs
≤ 1600 V ≤ 5200 V/µs
≤ 2200 V ≤ 7800 V/µs
Turn to turn insulation (phase-phase)
Type of
Peak voltage at
the motor
terminals
≤ 5900 V
PWM ≤ 9300 V
≤ 9300 V
PWM ≤ 14000 V
Inverter
dV/dt
Rise Time
(min.)
≥ 0,1 µs
Peak voltage at
dV/dt at the motor
the motor
terminals
terminals
≤ 500 V/µs ≤ 3400 V
≤ 2700 V/µs ≤ 5400 V
≤ 500 V/µs ≤ 5400 V
≤ 1500 V/µs ≤ 8000 V
www.weg.net
1
MTBP
3
3 Time between pulses
(min)
≥ 6 µs
Phase-ground insulation
dV/dt at the motor
terminals
≤ 500 V/µs
≤ 2700 V/µs
≤ 500 V/µs
≤ 1500 V/µs
Manual of Electric Motors 105