Safe Stop Functional Safety
The Integrated Safety Functions option module provides a networked STO (Safe Torque Off) function via an
EtherNet/IP™
network. It is also equipped for Integrated (drive-based) Timed SS1, Monitored SS1, and Safe Brake Control, which operate in the drive and are activated through the network safety connection.The Integrated Safety Functions option module also supports select controller-based EN/IEC 61800-5-2 safety functions operating in safety controllers that use the
EtherNet/IP™
network to communicate with the safety I/O. This support includes the safety function instructions that are provided on the Drive Safety tab in the Logix Designer application.The Integrated Safety Functions option module includes these features:
- Is designed to remove power from the gate firing circuits of the drive output power devices (IGBTs). With the power removed, the drive output power devices cannot turn on to generate AC power to the motor.
- Can be used in combination with other safety devices to satisfy the requirements of IEC 61508, EN/IEC 61800-5-2 and EN 62061 SIL 3, ISO 13849-1 PLe, and Category 4 for Safe Torque Off (STO).
When used for safe speed monitoring, the drive can be configured for single- or dual-feedback to achieve the following safety ratings:
- Single-feedback configurations using safety encoders provide up to SIL 2 PLd capability.
- Dual-feedback configurations provide up to SIL 3 PLe capability when discrepancy testing (either velocity, position, or both) is enabled. Safety functions that use position check have up to SIL 2 PLd capability. In this configuration, at least one encoder (the primary encoder) has to comply with SIL 2, PL d. The second encoder can be a standard encoder.
IMPORTANT:
The Integrated Safety Functions option module is suitable for performing mechanical work on the drive train or affected area of a machine only. It does not provide electrical safety.
ATTENTION:
Risk of injury or death exists.
The PowerFlex drive product can contain high voltages that can cause injury or death. Remove power from the drive and then verify that power has been discharged before performing any work on the drive or motor.
IMPORTANT:
Multiple safety option modules in a single drive are not allowed. Only one of these safety option modules can be installed in the drive:
- PowerFlex®750-Series Safe Torque Off option module (catalog number 20-750-S)
- PowerFlex®750-Series Safe Speed Monitor option module (catalog number 20-750-S1)
- PowerFlex®755/755T Integrated Safety - Safe Torque Off option module (catalog number 20-750-S3)
- PowerFlex®755/755T Integrated Safety Functions option module (catalog number 20-750-S4)
ATTENTION:
If two output IGBTs fail in the drive, when the Integrated Safety Functions option module has controlled the drive outputs to the Off state, the drive can provide stored energy for up to 180° of rotation in a 2-pole motor before torque production in the motor stops.
ATTENTION:
The safe torque off (STO) function only disables motor torque. A mechanical force on the motor shaft such as suspended loads, back pressure in a pump or fan, can cause motor rotation.
IMPORTANT:
Do not use this option module as a control for starting or stopping the drive.
Safety Certification
The
PowerFlex®
755 Integrated Safety Functions option module (catalog number 20-750-S4) is certified by TÜV Rheinland as suitable for use in integrated safety applications:
- Up to and including SIL 3 according to IEC 61508
- Up to and including SIL CL3 according to EN 62061
- Up to and including PLe (Category 4) according to ISO 13849-1.
In these applications, the removal of motion-producing power is considered to be the safe state. All components in the system must be chosen and applied correctly to achieve the desired level of operator safeguarding.
Provide Feedback