HANDLING. STORAGE, INSTALLATION 



Greater care is required for handling frameless dc torque motors than 

 for housed units or conventional ac motors. The armature, field, and brush 

 assembly are supplied as a matched set identified serially and should not 

 be interchanged with other components. They are packaged separately in 

 the shipping container. During unpacking and handling, and throughout 

 installation, care must be taken to avoid bending or distorting the brush 

 assembly springs, and to protect the commutator surfaces from scratching 

 or contamination by oil or fingerprints. The field is supplied with a 

 "keeper" ring, attached by magnetic force, which must not be removed 

 until the field is installed and the armature is in place. To do so will result 

 in approximately 1/3 reduction in torque sensitivity. 



Frameless units should be stored in nonmagnetic racks or containers 

 — the shipping container is suitable — to prevent interaction of magnetic 

 fields. Attraction of magnetic particles also should be avoided. Protect 

 the armature core from moisture with desiccant. 



14. Using the motor armature (with the 

 rotor spacer in place), push the 

 keeper out of the motor field. 



ATTENTION: Removing the keeper with- 

 out substituting it with 

 the field; 



- or placing the field on 

 steel shelves or benches, 

 unless separated from 

 the steel by at least 

 one-half inch of non- 

 magnetic material ; 



- or letting the field 

 come in contact with 

 the ferrous tools or 

 measuring instruments 



will demagnetize the field up to 50%. 



COMPONENT PARTS - 

 DEFINITIONS 



Armature. The rotating element. The wind- 

 ings are in this part. 



Commutator. A conductive segmented ring 

 on the armature, which allows electrical 

 power to be transferred to the winding from 

 the stationary element. 



Field. The stationary permanent magnet 

 assembly that produces the magnetic flux 

 field in the motor air gap. 

 Brush Assembly. The stationary insulating 

 ring, or segment supporting spring-loaded 

 electrical contacts (brushes), which slide on 

 the commutator to transfer the dc power. 

 Keeper. A magnetic steel ring installed on 

 the field to keep the magnets at full strength 

 until the armature is fully in place. The 

 normal keeper type is shown in the above 

 installation instructions. Other types some- 

 times are used for magnetic or assembly 

 reasons. 



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