OPERATION AND MAINTENANCE MANUAL
ID MOTORS
PAGE: 13
CODE: CTT52 EDITION: 03 RELEASE: APRIL 2019
Subject to technical changes without prior notice
The data given in all the documentation provided by VASCAT includes tolerances regarding the most relevant parameters shown
on the table 3:
Power
Efficiency
Inertia
Noise level
Speed
Power
Maximum
Torque
Pn < 150 kW
-15% (1-η)
+/-10%
+3dB
+/-5%
-2%
-7%
Pn > 150 kW
-10% (1-η)
+/-10%
+3dB
+/- 5%
-1%
-6%
Table 3:
Tolerances
3.3
Definitions
Duty
3.3.1
Three-phase induction motors are usually designed to develop their rated power in continuous service with no overheating
problems. However, most motors operate under a non-continuous type of service. Some motors are switched on for a few
moments only, others work all day, but they only charge up briefly, etc. The EN 60034-1 standard defines 10 main service types
and those summarised in the table below apply to ID motors:
Duty
Description
Definition
S1
Continuous service
Operation in constant charging status with sufficient duration to reach
thermal balance.
S2
Temporary service
Operation in constant charging status during a shorter period than
necessary to reach thermal balance, followed by a standby period that is
sufficient to cool down to ambient temperature.
S3
Intermittent regular service
Chain of identical services made up of a constant charging period
followed by a standby period.
S5
Intermittent regular service
with electrical braking
Chain of identical services made up of a start-up period, a constant
charging period and an electrical braking period followed by a standby
period.
S6
Regular uninterrupted
service with intermittent
charging
Chain of identical services made up of a constant charging period
followed by a period of load-free operation.
S7
Regular uninterrupted
service with intermittent
charging and electrical
braking.
Chain of identical services made up of a start-up period, a period of
constant charging, a period of load-free operation and a period of
electrical braking.
Table 4:
Duty
