Siemens SIMOTICS XP 1MB155, Operating Instructions Manual

Page: 44 / 152

Preparations for use
4.9 Noise emission
1MB155 / 1MB555
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Operating Instructions, 03/2018, A5E41926185A
4.9 Noise emission
CAUTION
Hearing damage when operating three-phase motors
If the permissible sound pressure level is exceeded, hearing damage can occur when
operating three-phase motors at their rated power.
Observe the maximum permissible sound pressure level according to the ISO 1680
standard. The maximum permissible sound pressure level is 70 dB (A).
4.10 Voltage and frequency fluctuations during line operation
Maintain the ranges stated on the rating plate and in the documentation (e.g. range B acc. to
IEC/EN 60034-1) for voltage fluctuation (±10 %) and frequency fluctuation (±2 %) at all
times.
NOTICE
Overheating of the winding
Tolerances must not be exceeded. Impermissibly high winding temperatures and therefore
long-term damage to the machine can result.
Keep within the permissible tolerance for voltage and frequency.
Every machine must be protected against an inadmissible temperature rise. Observe the
following notes:
● Protect every machine according to IEC/EN 60079–14 using a current-dependent,
delayed circuit breaker with phase failure protection according to IEC/EN 60947 or a
similar device in all phases.
● Set the protective device to the rated current (value is stamped on the rating plate).
● Protect the windings in a delta connection in such a way that the tripping unit or relay is
connected in series with the winding phases. When selecting and setting the tripping unit,
define the rated value of the phase current. The phase current is 0.58 times the rated
machine current. Any thermal machine protection via direct temperature monitoring to be
used in addition to the machine circuit breaker is specified on the rating plate if required.