EL6900

Product information

Product Overview

The EL6900 is the TwinSAFE Logic terminal: the link unit that processes safe input and output signals inside an EtherCAT Terminal station, using TwinSAFE/Safety over EtherCAT. Beckhoff specifies it to DIN EN ISO 13849-1:2008 Cat. 4 / PL e and EN 61508:2010 SIL 3.

It is not an ordinary I/O terminal. It is the safety logic itself, sitting on the same DIN rail as the standard I/O, programmed with the TwinCAT Safety Editor rather than with the standard PLC program.

Why Buyers Specify This Model

Safety logic on the standard rail, not in a separate device

Conventionally, machine safety is a separate system: a dedicated safety relay or a separate safety PLC, wired independently from the standard control. TwinSAFE puts the safety logic in a terminal beside the standard I/O, communicating over the same EtherCAT network.

The practical consequences are fewer components, less cabinet wiring and one engineering environment instead of two. The safety function itself remains independent: the EL6900 processes safety signals in its own path, and the standard controller cannot influence it.

What “link unit” means in practice

Beckhoff describes the specification as a link unit between safe input and output signals. It reads safe inputs (from TwinSAFE input terminals) and drives safe outputs (to TwinSAFE output terminals), executing the configured safety logic between them.

The cycle time is approximately 500 µs, depending on project size, and the fault response time is at most the parameterisable watchdog time. That is the figure that matters for a risk assessment: the reaction time of the safety function is bounded by it.

Approvals, current consumption and mounting

Current consumption is typically 188 mA from the E-bus with no power contact consumption, weight approximately 50 g, protection rating IP20. Beckhoff specifies the installation position as horizontal — a constraint worth noting, because the rest of the terminal range allows variable mounting.

The Ex marking published by Beckhoff covers ATEX II 3G Ex ec IIC T4 Gc, IECEx Ex ec IIC T4 Gc and cFMus Class I Division 2 / Class I Zone 2. Safety approvals and the safety standard are separate matters from the Ex rating; both are reproduced here as published.

Technical Specifications (Official Beckhoff Data)

Parameter	Official value
Specification	link unit between safe input and output signals
Protocol	TwinSAFE/Safety over EtherCAT
Cycle time	approx. 500 µs/according to project size
Fault response time	≤ watchdog time (parameterizable)
Current consumption power contacts	–
Current consumption E-bus	typ. 188 mA
Installation position	horizontal
Safety standard	DIN EN ISO 13849-1:2008 (Cat. 4, PL e) and EN 61508:2010 (SIL 3)
Weight	approx. 50 g
Protection rating	IP20
Ex marking	ATEX: / II 3G Ex ec IIC T4 Gc / IECEx: / Ex ec IIC T4 Gc / cFMus: / Class I, Division 2, Groups A, B, C, D / Class I, Zone 2, AEx ec IIC T4 Gc

Specifications are Beckhoff’s official product data for the EL6900. Safety certification figures are reproduced exactly as published by Beckhoff.

Housing, Installation and Wiring

Data	Official value
Design form	compact terminal housing with signal LEDs
Material	polycarbonate
Installation	on 35 mm DIN rail, conforming to EN 60715 with lock
Side by side mounting by means of	double slot and key connection
Marking	labeling of the BZxxxx series
Wiring	solid conductor (s), flexible conductor (st) and ferrule (f): spring actuation by screwdriver
Connection cross-section	s*: 0.08…2.5 mm², / st*: 0.08…2.5 mm², / f*: 0.14…1.5 mm²
Connection cross-section AWG	s*: AWG28…14, / st*: AWG28…14, / f*: AWG26…16
Stripping length	8…9 mm
Current load power contacts	I max : 10 A
Dimensions (W x H x D)	12 mm x 100 mm x 68 mm

Material Compliance

The following is Beckhoff’s published material compliance data for this product, reproduced unchanged. Beckhoff notes that absence of a substance is not verified by analytical tests.

Item	Official statement
REACH SVHC	no
POP	compliant
RoHS	compliant with exemption
RoHS exemption	7c-I: Lead-containing electrical and electronic components in glass and ceramic materials, excluding dielectric ceramics in capacitors
China-RoHS	www.beckhoff.com/china-rohs-io
CA Prop65	www.beckhoff.com/prop65

Official Documentation

Every figure in the table above is published by Beckhoff. We reproduce it rather than paraphrase it, so that you can check it against the manufacturer’s own documentation:

• Beckhoff official product page — EL6900 — the source of every specification on this page.
• Beckhoff official documentation for EL6900 — downloadable PDF from Beckhoff’s documentation server.
• Canonical Beckhoff documentation link for EL6900.

Ordering This Part

Tell us the model and, where an order code exists, the complete code — Beckhoff variants differ in ways that matter, as set out above. For discontinued models, a nameplate photograph is the fastest way to confirm exactly what you have.

• Exact model or order code (including any suffix such as -0111 or -ES variants)
• Quantity required
• Whether you need the terminal alone or a complete station with coupler and power supply
• For replacements: a photo of the existing nameplate or the old order code

We confirm availability and condition before quoting. We do not publish stock levels or lead times on this page because they change; ask and we will answer specifically for your requirement.

Frequently Asked Questions

Is the EL6900 a PLC?

It is a safety logic terminal, not a standard PLC. It executes TwinSAFE safety logic between safe inputs and safe outputs. The machine’s standard control program runs separately, on the controller.

What safety level does it achieve?

Beckhoff specifies DIN EN ISO 13849-1:2008 Cat. 4 / PL e and EN 61508:2010 SIL 3. The achieved level for a complete safety function also depends on the sensors and actuators in that function, not on this terminal alone.

What is the response time of the safety function?

The cycle time is approximately 500 µs depending on project size, and the fault response time is at most the parameterisable watchdog time. Use those figures in your risk assessment rather than assuming a value.

Can it be mounted in any position?

No. Beckhoff specifies horizontal installation for the EL6900. That differs from most other EtherCAT Terminals, which allow variable installation position.

What else do I need for a TwinSAFE system?

Safe input and output terminals, the TwinCAT Safety Editor for configuration, and a safety concept that is validated for the application. Configuration is a separate engineering task from the standard PLC program — if you are new to TwinSAFE, plan for training or for support.