BECKHOFF EL1904 User Manual
Page 3
Table of contents
EL1904
1
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