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Entry type: FAQ Entry ID: 109740097, Entry date: 09/15/2016

SINAMICS, Safety Integrated: deactivation of the speed acceleration monitor (SAM) with overlaid SOS delay time

  • Entry
  • Associated product(s)
When using a SINAMICS with CU310-2 / CU320-2 and software version V4.7 respectivly SIMOTION D4xx-2 and software version V4.4 together with the Safety Extended functions, the Safe Acceleration Monitoring (SAM) is executed correctly from software versions V4.7 HF24 respectivly V4.4 HF17 after selecting SS2/STOP C with a higher-level SOS delay time.

In SINAMICS Software Version V4.7, the following incorrect behavior may occur in combination with safety configuring. If, after selecting SS2 and during the delay time SS2 -> SOS active (p9552) respectively STOP D ->  SOS active (p9553), SOS is directly selected in addition, SOS is only activated following expiry of the delay time SOS -> SOS active (p9551) and only then reported to be active. The speed acceleration monitor SAM, however, is already deactivated following expiry of p9552. During this time period, the motor could accelerate without monitoring. An internally performed risk analysis showed a very low risk of injury resulting from this behavior. A machine / system-specific assessment should be performed nevertheless.

If one of the following statements applies, there is no additional risk resulting from the above-described behavior and no measures (upgrade with hotfix V4.7 HF24) have to be adopted:

  • The safety function SS2 and the stop reaction STOP C are not used
  • The direct selection of SOS is not used.
  • Simultaneous switching processes with SS2 and direct SOS selection can be excluded. In this case, however, you must also consider the occurrence of a STOP C as error reaction of another safety function during expiry of the delay time from p9551 following explicit SOS selection.
  • In terms of safety, the application reacts to the status SOS only actively, that means, without SOS active, there is no risk (e.g. protection doors are closed).
  • The time in p9551 is set to a minimum value ensuring that no dangerous situation can occur during this period (e.g. accelerating axes reach a critical speed).

Affected products
SINAMICS S120, S150, G150, G130, S120 Cranes and SIMOTION D4xx-2, independently of the Power Module used (type)
This concerns:

  • SINAMICS software versions: V4.7 smaller than HF2
  • SIMOTION D4xx-2 software versions V4.4 smaller than HF24

The above-described risk must be assessed for specific machines / systems and a specific measure has to be adopted to upgrade the system to the following software, if required:

  • SINAMICS V4.7 HF24 (internal version: V04.70.35.62)
  • SIMOTION V4.4 HF17 (with SINAMICS integrated V4.7 HF24)
Security information
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