The integrated safety functions of SINAMICS S110 provide highly effective application-oriented protection for personnel and machinery.

SINAMICS S110 offers Extended Functions (SS2, SOS, SLS, SDI, SSM) in addition to Basic Functions (STO, SS1, SBC).

The Safety Integrated functions are implemented electronically and therefore offer short response times compared to solutions with externally implemented monitoring functions.

The Safety Integrated functions are fully integrated in the drive system. They can be activated via fail-safe digital inputs on the CU305 Control Unit or via PROFINET or PROFIBUS with PROFIsafe.

As an alternative to controlling via terminals and/or PROFIsafe, there is also the option to parameterize several safety functions without selection. In this mode, after parameterization and a POWER ON, these functions are permanently selected.

Example:

"SLS without selection" can be used, for example, to monitor the maximum velocity to prevent the drive from exceeding a mechanical speed limit. For this purpose, using the "without selection" function, an F‑DI does not have to be used; an F‑CPU is also not required.

Safe speed/position sensing

Incremental encoders or absolute encoders can be used for safe sensing of the position values on a drive. Safe actual value sensing relies on redundant evaluation of the incremental tracks A/B that supply sin/cos signals of 1 V_pp. Only encoders of the type whose A/B track signals are created and processed using purely analog techniques can be used.

The encoder signals can be input via the Sensor Modules. As an alternative, motors with an integrated DRIVE-CLiQ interface can be used. The speed or position actual values are generated directly in the motor as safe values and are transferred to the Control Unit over safe communication via DRIVE-CLiQ.

The encoder must be mechanically attached in such a manner that the encoder shaft is unable to unplug or slide off. For notes on this, see IEC 61800‑5‑2: 2007, Table D.16.

A list of Siemens motors that fulfill the electrical and mechanical requirements is available at:

https://support.industry.siemens.com/cs/document/33512621

Motors with DRIVE-CLiQ interface are connected directly to the CU305 Control Unit. A SINAMICS Sensor Module is required to evaluate the encoder signals of motors without a DRIVE-CLiQ interface.

Safe actual value sensing without encoder

Some safety functions can also be operated without safety-capable encoders; implementation effort is minimal. Existing systems in particular can be updated with safety technology without the need to change the motor or mechanical system.

The STO function can be used without any restrictions for all applications.

The SS1, SLS, SSM and SDI functions are permissible for applications in conjunction with asynchronous and SIEMOSYN motors where the load can never cause acceleration. An encoder that is used for the purposes of motor control has no significance for the safety functions here.

Licensing

The Safety Integrated Basic Functions do not require a license.

The Safety Integrated Extended Functions do require a license. It is of no consequence here which safety functions are used and how many. The license can be ordered as an option with the memory card. Alternatively, a single-user license can also be purchased.

Safe Brake Relay

The Safe Brake Control (SBC) function requires a Safe Brake Relay. The Safe Brake Relay allows safe control of electro-mechanical motor brakes.

The 24 V DC solenoid of the motor brake is directly connected to the Safe Brake Relay. External surge suppressors are not required. The cable harnesses for connection to the Power Module are included in the scope of supply.

With the Safe Brake Relay function, the brake is controlled in accordance with IEC 61508 SIL 2 and EN ISO 13849‑1 PL d and Category 3.