TwinSAFE

Choosing TwinSAFE components

TwinSAFE is configuration-driven — the hardware is just terminals on an EtherCAT network until the safety project is engineered, downloaded, and validated in TwinCAT. Replacement decisions need to account for the configuration as well as the hardware.

Specs to confirm before ordering:

Exact Beckhoff part number (EL1904, EL2904, EL6900, EL6910, KL1904, KL2904, etc.)
Generation — EL6900 (FSoE master, legacy) vs. EL6910 (current TwinSAFE 2 logic terminal)
Number of safe inputs/outputs on the terminal
Safety performance: SIL 3 / PL e
TwinCAT version compatibility (TwinCAT 2 vs. TwinCAT 3) and Safety Editor version
FSoE address — set in the safety project, not on the device
Mounting: EtherCAT terminal rail vs. K-bus rail (KL- prefix is K-bus, EL- prefix is EtherCAT)

Common gotchas: EL6900 and EL6910 are not drop-in replacements for each other — the safety project must be re-engineered for the newer terminal, and TwinCAT versions differ. KL-series K-bus safety terminals connect through a BC- or BK-series bus coupler; the coupler must be in the system and online for the safety terminals to operate. Each TwinSAFE terminal has an FSoE address configured in the safety project; replacing a terminal requires re-downloading the safety project from a TwinCAT engineering workstation to set the address on the new hardware. Without the original safety project files, a replacement terminal is hardware that does nothing until safety logic is re-developed.

Typical applications: distributed safety on Beckhoff-controlled machines, integrated machine safety on EtherCAT-based motion systems, OEM machinery using TwinCAT NC/CNC with TwinSAFE for safe motion, and retrofit of older machines to TwinSAFE-based safety. On Beckhoff-based installations, TwinSAFE replacement is straightforward when the safety project is backed up; without the project, a separate re-engineering effort is required.

For obsolete TwinSAFE terminals, send the Beckhoff part number for a sourcing quote.

Do you stock obsolete TwinSAFE terminals?

Yes. Discontinued KL1904/KL2904 first generations, retired EL6900, and earlier EL-series safety terminals are sourced through our supplier network.

Will my TwinSAFE project work on a replacement terminal?

If the part number and firmware match, yes — the safety project is downloaded from TwinCAT and the FSoE address is assigned to the new hardware. Across firmware revisions, project verification or re-validation is typically required.

EL6900 vs. EL6910 — are they interchangeable?

No. They use different TwinSAFE generations (1 vs. 2), different Safety Editor versions, and different project formats. Migrating from EL6900 to EL6910 is a re-engineering exercise.

What if I don't have the TwinSAFE project file?

Then a replacement terminal is hardware-only. The safety logic must be redeveloped in TwinCAT Safety Editor by an engineer with the safety circuit drawing and validated safety functions list.

Do you stock the matching non-safety EL/KL terminals?

Yes — most standard EL- and KL-series I/O terminals (non-safety) are stocked or sourced. Send a bill of materials for a consolidated quote.

What is the warranty?

12-month functional warranty on the terminal. Safety-function performance in the application is the integrator's responsibility, independent of the device warranty.

Beckhoff EJ1918 EtherCAT plug-in module

Beckhoff EJ2918 EtherCAT plug-in module

Beckhoff EL1852 EtherCAT Terminal

Beckhoff EL1904 EtherCAT Terminal

Beckhoff EL1918 EtherCAT Terminal

Beckhoff EL2904 EtherCAT Terminal

Beckhoff EL2911 EtherCAT Terminal

Beckhoff EL2912 EtherCAT Terminal

Beckhoff EL6900 EtherCAT Terminal communication interface

Beckhoff EL6910 EtherCAT Terminal communication interface

Beckhoff EL6930 EtherCAT Terminal communication interface

Beckhoff EP1957-0022 EtherCAT Box

Beckhoff KL1904 Bus Terminal

Beckhoff KL2904 Bus Terminal

Beckhoff KL6904 Bus Terminal

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