Bosch DOK-MOTOR-MCL Series, Project Planning Manual

Page: 108 / 196

Fig. 9-8: Heating up and cooling down of an electrical machine
Heating up
ϑ
e
Final over temperature in K
ϑ
a
Initial over temperature in K
t Time in min
t
th
Thermal time constant in min (see motor data sheet)
Fig. 9-9: Heating (overtemperature) of an electric machine
Final over temperature Since the final over temperature is proportional to the power loss, the expec‐
ted final over temperature ϑ
e
can be estimated according to:
P
ce
Continuous power loss or average power loss over cycle dura‐
tion in W (see chapter 11.4 "Determining the drive power" on
page 146 )
P
vN
Nominal power loss of the motor in W
ϑ
emax
Maximum final over temperature of the motor in K
F
eff
Effective force in N (from application)
F
dn
Continuous nominal force of motor in N (see motor data sheet)
Fig. 9-10: Expected final over temperature of the motor
Bosch Rexroth AG DOK-MOTOR*-MCL********-PR05-EN-P 106/193
Rexroth IndraDyn L Ironless Linear Motors MCL
Application and construction instructions