Safety information
2.6 ATEX / IECEx
SIRIUS 3RW50 soft starter
46
Manual, 09/2019, A5E35628455002A/RS-AA/001
Setting the rated motor operational current
Set the 3RW50 soft starter to the rated operational current of the motor as stated on the type
plate or design test certificate of the motor.
Tripping class (electronic overload protection)
Make sure that the motor and the cables are dimensioned for the selected tripping class.
Note that the trip class "CLASS OFF" when operating motors in hazardous areas is only
permissible if a "PTC thermistor type A" temperature sensor is used.
The rated data of the 3RW5 soft starter relates to normal starting (CLASS 10E). For heavy
starting (> CLASS 10E), you may have to overdimension the 3RW5 soft starter.
Parameterizing the motor protection functions (RESET setting)
Note that the "Auto RESET" setting is not permissible when operating motors in hazardous
areas.
Short-circuit protection
The 3RW50 soft starter does not have short-circuit protection. Make sure that short-circuit
protection is provided.
Line protection
Avoid impermissibly high cable surface temperatures by correctly dimensioning the
cross-sections. Select a sufficiently large conductor cross-section.
Cyclic test of the motor protection functions
Only perform the Self-test (user-test) (Page 179) locally by means of the RESET / TEST key
or the 3RW5 HMI High Feature to ensure that the correct 3RW50 soft starter is tested. Only
in this way can the certified motor overload protection according to ATEX / IECEx be
guaranteed.
On soft starters in ATEX / IECEx applications, perform the Self-test (user-test) (Page 179)
during commissioning and periodically at intervals of no more than 36 months.
