S4 duty motor

The rest periods are long enough for the motor to reach ambient temperature. S Intermittent periodic duty , Sequential, identical run and rest cycles with constant load. Temperature equilibrium is never reached.

Starting current has little effect on temperature rise. S, Intermittent periodic duty with starting, Sequential, .

Thermal equilibrium is not reached during the cycle.

S Intermittent periodic duty with electric .

The continuous load is referred to as SDuty Cycle. Electric motors can be used at various Duty Cycles, short-term or intermittent (S S S, etc.). A higher power output may be achieved whilst used at short-term or intermittent duty.

According to this standar Sduty rating is short time duty : motors using this duty cycle adapt to constant load. Motor needs long stop for total cooling between each start. Generally, the motors assigned duty type S Sand Sare considered for crane applications.

The crane duty motors are specially designed to offer satisfactory performance and long lives for service on the cranes and hoists.

But the operating time for all motors are not the same. Depending on this, concept of motor duty class is . These periods being too short to attain thermal equilibrium during one duty cycle (see Fig.3). This has resulted various options for cranc manufacturers in interpreting thc duty as follows: S3- CDF.

Some manufacturers are also specifying. The implication of such varying duty specification in sclecting motor frame size is shown in Tablc 1. S3: Intermittent periodic duty -type without starting. S: Intermittent periodic duty with starting. S5: Intermittent periodic duty with starting and electrical braking 2. Long starting current duration while accelerating high- . MENZEL crane motors for the heaviest lifting operations, with up to 6starts per hour.

Crane duty motors or drives for hoisting facilities must be rated for short- term or periodic duty.

Die Aussetzbetriebe Sund Ssind so vielfältig, dass Angaben nur unter klar definierten Randbedingungen möglich sind. Für die genaue Dimensionierung eines Motors für die Schaltbetriebsarten Sund Ssind daher neben der Beharrungsleistung folgende Angaben notwendig:. Integral motor controls shall be microprocessor based and include mechanically and electrically interlocked reversing contactors for ON-OFF duty and solid state contacts.

Ii These motors are specially designed for crane applications. Both wound rotor (slip ring) motors and cage motors are used.