Beckhoff EL2911 User Manual

Operation
EL2911 and EL2911-220040 Version: 2.0.0
5.3.4.1 Project design limits of EL2911
Project design limits
The maximum project design size for EL2911 is determined by the available memory. This is
managed dynamically. The values specified in the following table are therefore only guide values
and may differ from the actual values, depending on the safety project.
NOTE
Execution time of the logic function
The execution time of the logic program - with identical logic program - will typically be longer compared to
the EL6910, since the safe I/O signals must be processed additionally. This also has a corresponding effect
on the processing of the I/O signals, since with increasing project size these can only be evaluated with a
lower frequency.
Process image size max. 1486byte per data direction
(maximum memory size 0x1E00 for 3 buffers, ie with the same size of
input and output process data, a maximum size of 1280 bytes per data
direction is possible. Only straight start addresses are possible, so fill
bytes must be taken into account)
TwinSAFE connections 128 max.
(up to 255 CRCs in total; 1 CRC is required for a TwinSAFE connection
with 1 or 2 byte safe data.)
Safe data per TwinSAFE
connection
maximum 126byte (telegram length 255byte)
TwinSAFE blocks maximum 512 (when using ESTOP function blocks with complete input
and output mapping, other function blocks can lead to a smaller
maximum number)
TwinSAFE groups 128 max.
TwinSAFE user 40 max.
Standard PLC inputs dynamic (memory-dependent), max. 1484byte
Standard PLC outputs dynamic (memory-dependent), max. 1484byte
NOTE
Project development
TwinCAT 3.1 Build 4022.25 or newer is required to use the internal logic functions. If the EL2911 is used as
TwinSAFE slave with the default project, at least an EL6910, EK1960 or newer logic component is required
as TwinSAFE master.

Beckhoff EL2911 Specifications

General

Brand	Beckhoff
Model	EL2911
Category	I/O Systems
Language	English