Emcee 1004156, User Manual

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Technical data 3-phase motors-English Rev.1.1 - 31-12-2005
AC INDUCTION THREE-PHASE MOTORS
Three-phase cage motors driven by frequency converters
Maximum converter output voltage 500V at peak voltages Û ≤ 1460 V and du/dt ≤ 13 kV/us. For higher converter output
voltages or stresses, a special insulation is required.
With square characteristic of the load torque, motors can be driven with their rated torque.
For constant torque, the rated torque of motors with internal cooling must be reduced due to reduced cooling air inlet.
Depending on the control range, the use of an external fan would be advisable.
See the below diagram for the thermal maximum-toque curve for approximate determination of the required torque
reduction with constant load torque curve.
Some electric motors with brake are limited to a maximum speed of 1500 rpm (50 Hz with 4 poles
motors) due to the construction of the brakes. In case speeds over 50 Hz. are required with braked
motors please consult EMCÉ for the possibilities.
Maintenance
Before carrying out any work on the motor, disconnect it and secure it against restarting.
Cleaning
Depending on the local conditions, air passages should be cleaned regularly.
Bearing lubrication
Maintenance-free life for motors with permanent lubrication at ambient temperature of 40° C and service at 50 Hz:
2 and 4/2 pole motors : 10,000 h.
4 and more pole motors : 20,000 h.
However, the maximum period of maintenance-free operation is four years. The ball bearings and the bearing caps
should then be washed with petrol or benzene. If necessary, replace the bearings. Fill the spaces between the balls and
the roller tracks as well as the grease compartments half with grease. Coat shaft bushings in the bearing caps or end
shields with a thin layer of grease. Permanently greased bearings (2RS and 2Z bearings) cannot be washed and
regreased. Such bearings must therefore be replaced.
Ball bearings with regreasing device and grease slinger
From frame size 280 upwards the motors are equipped with regreasing device and grease slinger.
First lubrication is made with grease K3N to DIN 51 825 (lithium-based, water resistant to DIN 51 807 part 1: grade 0 or
1).
Regreasing interval and required quantity of grease is indicated on the rating plate. Bearings and bearing caps must be
washed with petrol or benzene when they have been regreased twelve times.