en – Original instructions
e-IXPSA – Additional Installation, Operation and Maintenance Manual
25
4.5.4
Overload protection
DANGER: Potentially explosive atmosphere hazard
Always use a motor protector approved for EX motor protection.
1.
Install an appropriate motor protector in the control panel, with D curve in accordance with
the current shown on the data plate.
2.
Calibrate the motor protector depending on the use of the motor:
•
With full load, comply with the nominal current value on the data plate.
•
With partial load, comply with the value of the operating current measured with a
current pincer.
4.5.5
Operation with frequency converter (VSD)
WARNING:
If a variable speed application is required, refer to the instructions and catalogues of the motor
and frequency converter manufacturers.
DANGER: Potentially explosive atmosphere hazard
Check if the frequency converter is suitable to operate in potentially explosive atmospheres.
DANGER: Potentially explosive atmosphere hazard
Check if the electric motor is suitable to operate in potentially explosive atmospheres
when connected to a frequency converter.
•
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 (available on request) and a sinusoidal
filter.
NOTE:
The above table is provided by way of non-exhaustive example. Always refer to the motor
manual.
