Functional Safety For Frequency Converters, Upgradable (+Bef2); Functional Safety Options; Functional Safety System Description; Safety Functions - Danfoss iC7 Series Operating Manual

Operating Guide | iC7-Automation Functional Safety

Functional Safety for Frequency Converters, Upgradable (+BEF2)

4

Functional Safety Options

4.1
Functional safety option +BEF2 includes Safe Torque Off (STO) and Safe Stop 1 time-controlled (SS1-t) safety functions. Drives with +BEF2
also include an advanced safety unit, which enables configuring functional safety parameters using MyDrive® Insight.

Functional Safety System Description

4.2
An additional advanced safety unit is used to implement safety functions in accordance with the standard EN IEC 61800-5-2 in iC7-
Automation frequency converters with +BEF2.
The advanced safety unit handles the safe I/O and the monitoring of active safety functions. The advanced safety unit does not handle
the controls of the AC drive. The AC drive can be controlled, for example, with the drive application, or the external process control
system. The advanced safety unit currently supports AC drives connected to TN or TT grid types. Support for more grid types is planned
for future releases.
The advanced safety unit can be controlled with the digital I/Os and over safe fieldbus, where applicable.

Safety Functions

4.3

Overview of Frequency Converters with STO and SS1-t (+BEF2)

4.3.1
Frequency converters with STO and SS1-t (+BEF2) provide the following safety functions:
Safe Torque Off (STO) as defined by EN IEC 61800-5-2:2017.
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Stop category 0, as defined in EN IEC 60204-1:2018.
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Safe Stop 1 time-controlled (SS1-t), as defined by EN IEC 61800-5-2:2017.
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Stop category 1, as defined in EN IEC 60204-1:2018.
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The Safe Torque Off (STO) function is a component in a safety control system. STO prevents the unit from generating the power required
to rotate the motor.
With SS1-t, the motor decelerates within a specified deceleration time. STO is activated at the end of a deceleration time.
Both safety functions are designed and approved suitable for the requirements of:
Category 3 in EN ISO 13849-1
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Performance Level "e" in EN ISO 13849-1
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SIL 3 in IEC 61508 and EN 61800-5-2
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Both functions are available for iC7 drives with functional safety plus code +BEF2. Specific hardware revisions are listed in the appendix
of the functional safety certificate.
The frequency converters are fitted with a dual-channel, galvanically isolated input, and an STO feedback signal for diagnostic purposes.
All control inputs and outputs are galvanically isolated from supply voltage (PELV) and other high-voltage terminals, unless otherwise
specified.
Select and apply the components in the safety control system appropriately to achieve the required level of operational safety.
Before integrating and using STO in an installation, carry out a thorough risk analysis on the installation to determine whether the
STO functionality and safety levels are appropriate and sufficient.
26 | Danfoss A/S © 2024.08
Functional Safety for Frequency Converters, Upgradable (+BEF2)
NOTICE
AQ319741840653en-000401 / 136R0268