Siemens 6ES5775-3AA21 Bus Coupling Module

Why This Bus Coupling Module Connects Your SINEC Network

This bus coupling module links SIMATIC S5 controllers to SINEC L2 networks. You get a reliable Siemens 6ES5775-3AA21 for industrial communication tasks. It handles data exchange between multiple PLC stations. Therefore, your system can share I/O data without complex wiring.

Technical Specifications and Physical Details

The Siemens 6ES5775-3AA21 features one SINEC L2 bus interface on its front panel. It supports baud rates up to 1.5 Mbps for fast data transfer. This module fits into a standard S5 rack slot. Its dimensions measure approximately 250 mm in width and 25 mm in height. The unit weighs around 0.42 kg for straightforward installation. This coupling module stores no configuration data internally. Instead, the CPU holds all network parameters and station addresses. Consequently, you lose no settings during a module replacement.

Below is the detailed breakdown of the hardware specifications.

Parameter	Specification
Product Model	6ES5775-3AA21
Product Type	Bus Coupling Module
Brand	Siemens
Family	SIMATIC S5 / SINEC L2
Network Protocol	SINEC L2
Max Baud Rate	1.5 Mbps
Number of Interfaces	1 bus port
Slot Requirement	1 S5 rack slot
Dimensions (W x H)	Approx. 250 x 25 mm
Approx. Weight	0.42 kg
Interface Type	Backplane + bus connector
Energy Storage	None (passive coupler)
Component Count	Single integrated board

Installation and Network Integration

This module connects to the SINEC L2 bus cable via a standard connector. You must terminate both ends of the bus line with resistors. The Siemens 6ES5775-3AA21 requires unique station addresses for each node. Therefore, set the DIP switches before connecting to the network. Always power off the rack when changing address settings. Hot adjustments will cause communication conflicts on the bus.