MGM
Built-in inverter motors
General Characteristics
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Built-in inverter motors consist of three-phase asynchronous electric motors with integrated frequency inverter. Power range is
between 0,37 kW and 15,0 kW while the motor frame is from 71 up to 160. The unit is made up of a high-efficiency 3-phase
asynchronous electric motor and a compact frequency inverter placed at the non-drive motor end. The basic construction is totally
enclosed, fan cooled (TEFC) and IP 55 protection degree. Built-in inverter motor is able to properly run also under heavy overload
conditions thanks to a high thermal reserve; the insulating materials are class F. The frame is made of aluminium alloy up to 132
frame size and of cast iron for above sizes. Shields and flanges are made of aluminium up to 90 frame size and of cast iron up to
160 frame size. The inverter housing is isolated from the motor in order to avoid heat transmission (patented system); the inverter
heat sink is self-ventilated. The frequency converter provided is one of the most advanced in design concept as well as used
components; control can be chosen between V/F type (frequency voltage control) or SLV type (Sensorless Vector Control). Built-in
inverter motors are easy to be programmed using only three buttons. Some functions, which automatically set parameters
(acceleration/deceleration times, V/f ratio etc.), make the programming easier. On request, motor can be arranged for main Bus fields
(Profibus, Interbus-S, Device-Net, etc.). Built-in inverter motors are designed to be real built-in frequency converter motors and not
just as a simple assembly of a standard motor with an inverter. The wiring connection is definitely simple to be made. All the adducted
features make the built-in inverter motor series high performance with strong structure.
Benefit and Applications
Built-in inverter motors represent an innovation in the automation field and they give manufacturers, automation designers and
machinery users new opportunities and great economical advantages. The ease of installation, the simple structure and the cost-
effectiveness of the system are pointed out as follows. Overall dimensions are extremely reduced; the couplings are the same of those
of a standard motor (special flanges and shafts can be supplied on request); protection class is IP 55 as standard (IP 56 is available
on request); electrical connections are extremely simplified; power and control are totally separated and placed on different terminal
boards; on request, motor can be equipped with built-in EMI filter (class A or B) in the way to avoid an external filter application; the
motor connection can be carried out through normal power supply cables, as shielded cables are no longer necessary in order to
comply with EMC regulations; SMI series motor can replace a mechanical speed variator, offering more advantages; the system
performance is very high in every operating condition; unit switchboard on which SMI motor is installed can be removed or reduced
as the inverter has no longer to be housed. SMI motor represents the solution to the actual needs related to automation systems where
actuating and surveying devices can find more places on unit board so to reduce the panel overall dimensions and the wiring costs.