4 10 Oper ating Instr u ctions CM Synchronous Ser v omotors Mechanical Inst allation 44 I nstalling the motor Carefully align the motor and the driven machine to avoid placing any unnecessary strain on the output shafts observe permitt ed overhung load and axial thrust forces Do not butt or hammer the shaft extension Use an appropriate cover to protect motors with VR forced cooling fan in vertical mounting positions from objects or fluids If a forced cooling fan is used ensure an unob structed cooling air supply and that air heated by other devices cannot be drawn in by the fan Balance components with a half keyway for subsequent mounting on the shaft with a half key motor shafts are balanced with a half key Installation in damp areas or in the open If possible arrange the motor and encoder connection so that the cable entries are pointing downwards Coat the threads of cable scre w fittings and filler plugs with sealant and tighten them well then coat them again Properly seal the cable entries Thoroughly clean the sealing surfaces of the connection space motorencoder connection before reassembly Fit new gaskets to replace embrittled ones Restore the anticorrosive coating if necessary Check the enclosure 45 I nstallation tolerances The motor or geared motor may only be moun ted or installed in the specified mounting position on a level and torsionally rigid s upport structure which is not subjected to shocks The surface temperature of the motor may exceed 65 C during operation Provide protection to avoid unintentional contact Shaft end Fla n ge s Diameter tolerance in accordance with DIN 748 I SO k6 at O 50 mm I SO m6 at O 50 mm C enter bore in accordance with DIN 332 shape DR Centering shoulder tolerance in accordance with DIN 42948 I SO j6 at O 230 mm I SO h6 at O 230 mm