BECKHOFF EL1904 User Manual

Operating instructions for

EL1904

TwinSAFE input terminal with 4 fail-safe inputs

Version: 1.5.1
Date: 30.01.2015

Table of contents

Table of contents

1 Foreword 3

1.1 Notes on the manual 3

1.1.1 Disclaimer 3

1.1.2 Brands 3

1.1.3 Patents 3

1.1.4 Copyright 3

1.1.5 Delivery conditions 3

1.2 Safety instructions 4

1.2.1 Delivery state 4

1.2.2 Operator's obligation to exercise diligence 4

1.2.3 Description of safety symbols 5

1.2.4 Origin of the document 5

1.2.5 Documentation issue status 6

2 System description 7

2.1 The Beckhoff Bus Terminal system 7

2.1.1 Bus Coupler 8

2.1.2 Bus Terminals 9

2.1.3 E-bus 9

2.1.4 Power contacts 9

2.2 TwinSAFE 10

2.2.1 The I/O construction kit is extended safely 10

2.2.2 Safety concept 10

2.2.3 EL1904, EL2904 – Bus Terminals with 4 fail-safe inputs or outputs 11

2.2.4 EL6900 - TwinSAFE logic terminal 11

2.2.5 The fail-safe principle (Fail Stop) 11

3 Product description 12

3.1 General description 12

3.2 Intended use 13

3.3 Technical data 14

3.4 Safety parameters 15

3.5 Characteristic curve of the inputs 15

3.6 Dimensions 16

3.7 Block diagram EL1904 17

EL1904 1

Table of contents

4 Operation 18

4.1 Installation 18

4.1.1 Safety instructions 18

4.1.2 Transport / storage 18

4.1.3 Mechanical installation 19

4.1.4 Electrical installation 22

4.1.5 Tested devices 27

4.2 Operation in potentially explosive atmospheres (ATEX) 28

4.2.1 Special conditions 28

4.2.2 Identification 29

4.2.3 Date code and serial number 29

4.2.4 Further ATEX documentation 29

4.3 Configuration of the EL1904 in the TwinCAT System Manager 30

4.3.1 Inserting a Beckhoff Bus Coupler 30

4.3.2 Inserting a Beckhoff Bus Terminal 30

4.3.3 Inserting an EL1904 30

4.3.4 Address settings on the TwinSAFE terminals 31

4.3.5 Entering a TwinSAFE address and parameters in the System Manager 32

4.4 Diagnostics 35

4.4.1 Diagnostic LEDs 35

4.4.2 Diagnostic objects 37

4.5 Maintenance 38

4.5.1 Cleaning 38

4.5.2 Service life 38

4.6 Decommissioning 39

4.6.1 Disposal 39

5 Appendix 40

5.1 Beckhoff Support and Service 40

5.1.1 Beckhoff branches and partner companies Beckhoff Support 40

5.1.2 Beckhoff company headquarters 40

5.2 Certificates 41

2 EL1904

Foreword

1 Foreword

1.1 Notes on the manual

This description is only intended for the use of trained specialists in control and automation technology
familiar with the applicable national standards. It is essential that the following notes and explanations are
followed when installing and commissioning these components.
The responsible staff must ensure that the application or use of the products described satisfy all the
safety requirements, including all the relevant laws, regulations, guidelines and standards.

1.1.1 Disclaimer

This documentation has been prepared with care. The products described are, however, constantly under
development. For this reason, the documentation may not always have been fully checked for
consistency with the performance data, standards or other characteristics described.
If it should contain technical or editorial errors, we reserve the right to make changes at any time and
without notice.
No claims for the modification of products that have already been supplied may be made on the basis of
the data, diagrams and descriptions in this documentation.

1.1.2 Brands

Beckhoff®, TwinCAT®, EtherCAT®, Safety over EtherCAT®, TwinSAFE® and XFC® are registered
trademarks of and licensed by Beckhoff Automation GmbH.
The use by third parties of other brand names or trademarks contained in this documentation may lead to
an infringement of the rights of the respective trademark owner.

1.1.3 Patents

The EtherCAT technology is patent protected, in particular by the following applications and patents:
EP1590927, EP1789857, DE102004044764, DE102007017835 with the corresponding applications and
registrations in various other countries.

The TwinCAT technology is patent protected, in particular by the following applications and patents:
EP0851348, US6167425 with the corresponding applications and registrations in various other countries.

1.1.4 Copyright

©

Beckhoff Automation GmbH & Co. KG.
The copying, distribution and utilization of this document as well as the communication of its contents to
others without express authorization is prohibited. Offenders shall be held liable for damages. All rights
conferred by patent grant or registration of a utility model or registered design are reserved.

1.1.5 Delivery conditions

In addition, the general delivery conditions of the company Beckhoff Automation GmbH & Co. KG apply.

EL1904 3

Foreword

1.2 Safety instructions

1.2.1 Delivery state

All the components are supplied in particular hardware and software configurations appropriate for the
application. Modifications to hardware or software configurations other than those described in the
documentation are not permitted, and nullify the liability of Beckhoff Automation GmbH & Co. KG.

1.2.2 Operator's obligation to exercise diligence

The operator must ensure that

 the TwinSAFE products are only used as intended (see section Product description);
 the TwinSAFE products are only operated in sound condition and in working order (see chapter

Cleaning).

 the TwinSAFE products are operated only by suitably qualified and authorized personnel.
 the personnel is instructed regularly about relevant occupational safety and environmental

protection aspects, and is familiar with the operating instructions and in particular the safety
instructions contained herein.

 the operating instructions are in good condition and complete, and always available for reference

at the location where the TwinSAFE products are used.

 none of the safety and warning notes attached to the TwinSAFE products are removed, and all

notes remain legible.

4 EL1904

Foreword

1.2.3 Description of safety symbols

The following safety symbols are used in these operating instructions. They are intended to alert the
reader to the associated safety instructions.

Serious risk of injury!

DANGER

WARNING

CAUTION

Failure to follow the safety instructions associated with this symbol directly endangers

the life and health of persons.

Caution - Risk of injury!

Failure to follow the safety instructions associated with this symbol endangers the life

and health of persons.

Personal injuries!

Failure to follow the safety instructions associated with this symbol can lead to injuries

to persons.

Damage to the environment or devices

Attention

Failure to follow the instructions associated with this symbol can lead to damage to the

environment or equipment.

Tip or pointer

Note

This symbol indicates information that contributes to better understanding.

1.2.4 Origin of the document

These operating instructions were originally written in German. All other languages are derived from the
German original.

EL1904 5

Foreword

1.2.5 Documentation issue status

Version Comment

1.5.1

1.5.0

1.4.0

1.3.1

1.3.0

1.2.1

1.2.0

1.1.0

1.0.0

 Certificate updated

 Company address amended
 Safety parameters extended

 Extended temperature range added
 Temperature measurement described
 Characteristic input curve added
 Description of date code extended

 Document origin added

 Clock output currents in the technical data amended
 Block diagram for EL1904 added

 Reference to EN 60068-2-29 removed

 ATEX notes amended
 Installation position / minimum distances extended
 Notes regarding overvoltage protection amended
 Notes regarding cable length and clocked signals extended
 Diagnostics for CoE object 0x800E described

 Minor amendments for EtherCAT
 Copyright / disclaimer modified
 Support / service addresses updated

 First released version

6 EL1904

System description

2 System description

2.1 The Beckhoff Bus Terminal system

The Beckhoff Bus Terminal system is used for decentralized connection of sensors and actuators to a
control system. The Beckhoff Bus Terminal system components are mainly used in industrial automation
and building management applications. In its minimum configuration, a bus station consists of a Bus
Coupler or a Bus Terminal Controller and Bus Terminals connected to it. The Bus Coupler forms the
communication interface to the higher-level controller, and the terminals are the interface to sensors and
actuators. The whole bus station is clipped onto a 35 mm DIN mounting rail (EN 50022). The mechanical
cross connection of the bus station is established via a slot and key system at the Bus Coupler and the
Bus Terminals.

The sensors and actuators are connected with terminals via the screwless Cage Clamp
system.

In order to accommodate the wide range of different communication standards encountered in industrial
automation, Beckhoff offers Bus Couplers for a number of common bus systems (e.g. EK1100 for
EtherCAT).

©

connection

EL1904 7

System description

2.1.1 Bus Coupler

Mechanical data

Mechanical data Bus Coupler

Material polycarbonate, polyamide (PA6.6).
Dimensions (W x H x D) 44 mm x 100 mm x 68 mm
Installation on 35 mm mounting rail (EN50022) with locking
Attachable by

double slot and key connection

Connection technology

Connection technology Bus Coupler

Wiring Cage Clamp® spring-loaded system
Connection cross-section 0.08 mm2 ... 2.5 mm2, stranded wire, solid wire
Fieldbus connection depending on fieldbus
Power contacts 3 spring contacts
Current load 10 A
Rated voltage 24 VDC

8 EL1904

System description

2.1.2 Bus Terminals

Mechanical data

Mechanical data Bus Terminal

Material polycarbonate, polyamide (PA6.6).
Dimensions (W x H x D) 12 mm x 100 mm x 68 mm or 24 mm x 100 mm x 68 mm
Installation on 35 mm mounting rail (EN50022) with locking
Attachable by double slot and key connection

Connection technology

Connection technology Bus Terminal

Wiring Cage Clamp® spring-loaded system
Connection cross-section 0.08 mm2 ... 2.5 mm2, stranded wire, solid wire
Fieldbus connection E-bus
Power contacts up to 3 blade/spring contacts
Current load 10 A
Rated voltage depends on Bus Terminal type

2.1.3 E-bus

The E-bus is the data path within a terminal strip. The E-bus is led through from the Bus Coupler through
all the terminals via six contacts on the terminals' side walls.

2.1.4 Power contacts

The operating voltage is passed on to following terminals via three power contacts. Terminal strip can be
split into galvanically isolated groups by means of potential feed terminals as required. The power feed
terminals play no part in the control of the terminals, and can be inserted at any locations within the
terminal strip.

EL1904 9

System description

2.2 TwinSAFE

2.2.1 The I/O construction kit is extended safely

With the TwinSAFE Terminals, Beckhoff offers the option of simply expanding the proven Bus Terminal
system, and to transfer the complete cabling for the safety circuit into the already existing fieldbus cable.
Safe signals can be mixed with standard signals without restriction. This saves design effort, installation
and material. Maintenance is simplified significantly through faster diagnosis and simple replacement of
only a few components.

The new ELx9xx series Bus Terminals only include three basic functionalities: digital inputs EL19xx,
digital outputs EL29xx and a logic unit EL6900. For a large number of applications, all sensors and
actuators can be wired on these Bus Terminals. The required logical link of the inputs and the outputs is
handled by the EL6900. For small to medium-sized configurations, the tasks of a fail-safe PLC can thus
be handled within the Bus Terminal system.

2.2.2 Safety concept

TwinSAFE: Safety and I/O technology in one system

 Extension of the familiar Beckhoff I/O system with TwinSAFE terminals
 Freely selectable mix of safe and standard signals
 Logical link of the I/Os in the EL6900 TwinSAFE logic terminal
 Safety-relevant networking of machines via bus systems

TwinSAFE protocol (Fail Safe over EtherCAT - FSoE)

 Transfer of safety-relevant data via any media (“genuine black channel”)
 TwinSAFE communication via fieldbus systems such as EtherCAT, Lightbus, PROFIBUS or

Ethernet

 IEC 61508:2010 SIL 3 compliant

Configuring instead of wiring: the TwinSAFE configurator

 Configuration of the TwinSAFE system via the TwinCAT System Manager
 System Manager for editing and displaying all bus parameters
 Certified function blocks such as emergency stop, operation mode, etc.
 Simple handling
 Typical function blocks for machine safety
 Any bus connection with the EL6900 TwinSAFE logic terminal

TwinSAFE logic Bus Terminal EL6900

 Link unit between TwinSAFE input and output terminals
 Configuration of a simple, flexible, cost-effective, decentralized safety controller
 No safety requirements for higher-level control system
 TwinSAFE enables networks with up to 65535 TwinSAFE devices
 TwinSAFE logic terminal can establish up to 128 connections (TwinSAFE connections).
 Several TwinSAFE logic terminals are cascadable in a network
 Safety functions such as emergency stop, protective door etc. are already included
 Suitable for applications up to SIL 3 according to IEC 61508:2010 and DIN EN ISO 13849-

1:2006 (Cat 4, PL e).

10 EL1904

System description

TwinSAFE digital input (EL1904) and output terminal (EL2904)

 All current safety sensors can be connected
 Operation with a TwinSAFE logic terminal
 EL1904 with 4 fail-safe inputs for sensors (24 V
 EL2904 with four safe channels for actuators (24 V

) with floating contacts

DC

, 0.5 A per channel)

DC

 Conforming to IEC 61508:2010 SIL 3 and DIN EN ISO 13849-1:2006 (Cat 4, PL e) requirements.

2.2.3 EL1904, EL2904 – Bus Terminals with 4 fail-safe inputs or outputs

The EL1904 and EL2904 Bus Terminals enable connection of common safety sensors and actuators.
They are operated with the EL6900 TwinSAFE logic terminal. The TwinSAFE logic terminal is the link unit
between the TwinSAFE input and output terminals. It enables the configuration of a simple, flexible and
cost-effective decentralized safety control system.

Therefore, there are no safety requirements for the higher-level controller! The typical safety functions
required for the automation of machines, such as emergency stop, protective door, two-hand etc., are
already permanently programmed in the EL6900. The user configures the EL6900 terminal according to
the safety requirements of his application.

2.2.4 EL6900 - TwinSAFE logic terminal

The TwinSAFE logic terminal is the link unit between the TwinSAFE input and output terminals. The
EL6900 meets the requirements of IEC 61508:2010 SIL 3, EN 954 Cat. 4 and DIN EN ISO 13849-1:2006
(Cat 4, PL e).

2.2.5 The fail-safe principle (Fail Stop)

The basic rule for a safety system such as TwinSAFE is that failure of a part, a system component or the
overall system must never lead to a dangerous condition. The safe state is always the switched off and
wattless state.

EL1904 11

Product description

3 Product description

3.1 General description

EL1904 - TwinSAFE digital four channel input terminal

The EL1904 is a digital input terminal for encoder with floating contacts for 24 V
4 fail-safe inputs.

With two-channel connection, the EL1904 meets the requirements of IEC 61508:2010 SIL 3, DIN EN ISO
13849-1:2006 (Cat 4, PL e), NRTL, UL508, UL1998 and UL991.

The TwinSAFE terminal has the typical design of an EtherCAT terminal.

. The Bus Terminal has

DC

12 EL1904