Operating mode parameters

Asynchronous motor operating mode parameters – this is:
– power consumption………………………………………Р1, kw;
– consumed line current…………………………………I1, A;
– efficiency…………………………..η, %;
– Power factor……………………………………….cos φ, OE;
– slip………………………………………………………s, OE;
– rotor speed……………………………………..n1, rpm.

The operating mode parameters are determined by the formulas:

where:
P2 – useful (given) power, kw;
U1 – applied voltage, V;
nc – synchronous speed, rpm;
f – mains frequency, Hz;
p – number of pole pairs;
M – rated torque, Н * м.

Motors can operate for a long time at ambient temperature, exceeding the maximum working. In this case, in order to avoid an unacceptable excess of the temperature of the windings, the power supplied to the motors must be reduced to the following values: