Siemens 6ES5490-8FB11 Terminal Block

Technical Specifications and Connection Design

This terminal block provides field wiring connections for Siemens SIMATIC S5 I/O modules. The Siemens 6ES5490-8FB11 simplifies cable termination and replacement for maintenance teams. You can mount this unit directly onto the front of compatible S5 modules. Its screwless spring-clamp design allows rapid wire insertion without special tools. The terminal block weighs approximately 0.12 kilograms. Its dimensions measure 12 cm in height, 7 cm in width, and 4 cm in depth.

Parameter	Specification
Brand	Siemens
Model	6ES5490-8FB11
Category	Terminal Block / Field Wiring Connector
Weight	0.12 kg
Height	12 cm
Width	7 cm
Depth	4 cm
Number of Terminals	20 terminals (2 rows of 10)
Terminal Type	Spring-clamp (cage clamp)
Wire Gauge Range	0.2 to 1.5 mm² (AWG 24 to 16)
Stripping Length	8 mm recommended
Rated Voltage	250V AC maximum
Rated Current	8 Amps per terminal
Connection Type	20-pin male header (mates with module)
Material (Housing)	Polyamide (PA66), UL94 V-0 rated
Material (Contacts)	Tin-plated copper alloy
Energy Storage	None (passive component)
Component Count	1 housing, 20 spring clamps, 1 locking lever

Spring-Clamp Technology and Wiring

The spring-clamp mechanism secures wires without screws or tightening tools. You simply insert a stripped wire into the terminal opening. The Siemens 6ES5490-8FB11 releases the wire by pressing a small orange lever. A flat-blade screwdriver activates the release mechanism for each terminal individually. The spring maintains constant pressure on the wire for reliable contact. Consequently, vibration will not loosen the connection over time. Each terminal accepts solid or stranded copper wire exclusively. You should not use tinned or ferruled wires in these terminals.

Module Compatibility and Mounting

This terminal block connects directly to S5-115U and S5-135U I/O modules. A 20-pin male header on the block mates with the module’s female connector. The Siemens 6ES5490-8FB11 includes a locking lever on the top edge. This lever secures the terminal block to the module for vibration resistance. You can remove the block without disturbing any field wiring. Consequently, module replacement takes only seconds instead of hours. The block carries printed terminal numbers for easy wire identification.

Installation and Wiring Guidelines

You must mount the terminal block onto the module before inserting the module into the rack. The locking lever must click into position for a secure connection. You should strip exactly 8 mm of insulation from each wire end. Longer strips risk short circuits between adjacent terminals. The Siemens 6ES5490-8FB11 requires no maintenance after installation. You should label each wire according to your electrical schematic drawings. The operating temperature ranges from -25°C to +70°C. The block does not require any power or configuration for operation.