Rotational Speed Limit Values; System-Inherent Frequencies - Siemens SIMOTICS XP 1MB 5/6 Series Operating Instructions Manual

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.
4.11

Rotational speed limit values

Danger as a result of resonance within certain speed ranges
At over-critical speeds, machines encounter resonance within certain speed ranges. Such
vibrations can reach impermissibly high levels. This can result in death, serious injury or material
damage.
• The controller must ensure that those speed ranges are blocked when the converter is in
operation. Please comply with the data on the blocked speed ranges specified in the electrical
data.
• The blocked speed ranges must be run through rapidly.
Machine damage due to excessively high speeds
Excessive rotational speed can lead to serious damage to the machine. This can result in death,
serious injury or material damage.
• Avoid operation above the permissible speed by using the appropriate control function.
• Comply with the speeds stamped on the rating plate and in the electrical data.
4.12

System-inherent frequencies

Excessively high vibration levels and system resonances can damage the machine set.
• Configure and match the system consisting of the foundation and machine set in such a way
that no system resonances can arise and result in the permissible vibration levels being
exceeded.
• Do not exceed the vibration values according to DIN ISO 10816-3.
1MB..5/6 shaft height 71 ... 355
Operating Instructions, 11/2023, A5E52779956A
Preparations for use
4.12 System-inherent frequencies
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