Nidec LEROY-SOMER FLSES 100 L, Руководство по пусконаладке и техническому обслуживанию

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Maintenance and service guide - LSPX-FLSPX ZONE 21 - Ex tb – LSES-FLSES ZONE 22 - Ex tc
5725 en - 2020.02 / c
When motors are supplied through a
separate frequency
inverter , or are used in a sufficient air-flow or if necessary
adapted so as to no longer be self-ventilated or equipped with
a backstop, they must be equipped with thermal sensors in the
windings (all frame sizes), on the front bearing housing (from
frame size 355 and above) and if relevant on the rear bearing
housing.
When the motor is equipped with auxiliary or forced ventilation
a device must prevent the main motor form operating in the
absence of ventilation.
The specific instructions given in the specific instruction
manuals must be followed if a drive is used.
In the event of several motors being supplied by the same
drive, for safety reasons individual protection must be provided
on each motor outlet (e.g. thermal relay).
Any changes to settings must be made by trained and
authorised personnel and in accordance with this guide.
- Operating position
When the motor is used in a position other than horizontally or
vertically, the front bearing housing must be equipped with a
thermal sensor and the shaft extension away from the fan
aligned downwards.
7.1.4 - Extreme operating conditions and
specific features
MOTOR CONNECTIONS
Leroy-Somer do not recommend any specific connections for
applications operating with a single motor on a single drive.
TRANSIENT OVERLOADS
Drives are designed to withstand transient overload.
When the overload values are too high, the system will
automatically shut down. Leroy-Somer motors are designed to
withstand these overloads, however in the event of very
repetitive operation we still recommend use of a temperature
sensor in the winding of the motor.
STARTING TORQUE AND CURRENT
Thanks to advances in control electronics, the torque available
when the motor is switched on can be adjusted to a value
between the rated torque and the variable speed drive
breakdown torque.
The starting current will be directly related to the torque (120 or
180%).
ADJUSTING THE SWITCHING FREQUENCY
The variable speed drive switching frequency has an impact
on losses in the motor and the drive, on the acoustic noise and
the torque ripple.
A low switching frequency has an adverse effect on temperature
rise in motors.
Leroy-Somer recommends a drive switching frequency of 3
kHz minimum.
In addition, a high switching frequency optimises the acoustic
noise and torque ripple level.
OPERATION AT SPEEDS HIGHER THAN THOSE
ASSIGNED BY THE MAINS FREQUENCIES
There are risks associated with the use of asynchronous
motors at high speed (speed higher than 3600 rpm):
• the cage may be damaged,
• bearing life may be impaired,
• there may be increased vibration,
• etc.
Motors are designed to operate at the speeds shown on the
nameplate (do not exceed the maximum speeds stated in our
technical catalogues).
When high-speed motors are used, they often need to be
adapted, and an in- depth mechanical and electrical design
exercise is needed .
CHOICE OF MOTOR
There are two possibilities:
a - The frequency inverter is not supplied by Leroy-Somer.
All the motors in this catalogue can be used with a frequency
inverter.
Depending on the application, motors will need to be derated
by around 10% compared to the motor operating curves in
order to guarantee that motors will not be damaged.
b - The frequency inverter is supplied by Leroy-Somer
As these motor-drive assemblies have been specifically
designed for use in combination, excellent performance is
guaranteed.
7.1.5 - Winding insulation and
recommendations relating to the mechanism
of rotation
The insulation systems used for Leroy-Somer motors and
recommendations for protection systems on the mechanisms
of rotation are indicated in our good practice guide ref. 5626.
7.1.6 - Nameplates on motors operating with
variable speed drives
The performance levels of motors operating using variable
speed drives, shown on the VV nameplate, are values obtained
with PWM supplies, with 360V at the motor terminals, in
continuous operation.
That is, for the following two cases:
• 400V rated voltage before drive + drive voltage drop
of 40V.
• A – 10% + drive with no voltage drop.
Please contact us for other cases.
Some applications require special construction specifications:
- Do not use a motor for lifting that is not rated S3 or S4.
- Do not use the motor with a different duty type from that on the
nameplate and in particular not in lifting applications.
INSTALLATION AND MAINTENANCE - LSPX-FLSPX ZONE 21 - Ex tb – LSES-FLSES ZONE 22 - Ex tc