Lenze MSEMA Series - Operating Modes of the Motor

Operang modes of the motor
Operang modes S1 ... S10 as specied by EN 60034-1 describe the basic stress of an electrical
machine.
In
connuous operaon a motor reaches its permissible temperature limit if it outputs the
rated power dimensioned for connuous operaon. However, if the motor is only subjected to
load for a short me, the power output by the motor may be greater without the motor
reaching its permissible temperature limit. This behaviour is referred to as overload capacity.
Depending on the duraon of the load and the resulng temperature rise, the required motor
can be selected reduced by the overload capacity.
The most important operang modes
Connuous
operaon S1 Short-me operaon S2
P
P
V
t
t
t
J
P
P
V
t
t
t
J
t
B
Operaon with a constant load unl the motor reaches the thermal
s
teady state. The motor may be actuated connuously with its rated
power.
Operaon with constant load; however, the motor does not reach the
thermal steady state. During the following standsll, the motor winding
cools down to the ambient temperature again. The increase in power
depends on the load duraon.
Intermient
operaon S3 Non-intermient periodic operaon S6
P
P
V
t
t
t
J
t
S
t
L
t
B
P
P
V
t
t
t
J
t
S
t
L
t
B
Sequence of idencal duty cycles comprising operaon with a constant
load and sub
sequent standsll. Start-up and braking processes do not
have an impact on the winding temperature. The steady-state is not
reached. The guide values apply to a cycle duraon of 10 minutes. The
power increase depends on the cycle duraon and on the load period/
downme rao.
Sequence of idencal duty cycles comprising operaon with a constant
load and subsequent no-load operaon. The motor cools down during
the no-load phase. Start-up and braking processes do not have an
impact on the winding temperature. The steady-state is not reached. The
guide values apply to a cycle duraon of 10 minutes. The power increase
depends on the cycle duraon and on the load period/idle me rao.
P Power P
V
Power loss
t Time t
B
Load period
t
L
Idle me t
S
Cycle
duraon
ϑ Temperature
Appendix
Good t
o know
Operang modes of the motor
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