Siemens 6ES5490-7LA11 Front Connector

Physical Dimensions and Mechanical Construction

The Siemens 6ES5490-7LA11 connects field wiring to SIMATIC S5 I/O modules. This connector measures 120mm in height, 45mm in width, 55mm in depth. You can snap this unit onto any standard S5 front panel without special tools. The connector weighs 0.15 kilograms , making it easy to handle during installation.

Internal Architecture and Component Details

The Siemens 6ES5490-7LA11 contains 52 individual components on its single PCB. Twenty gold-plated contact pins provide reliable signal transmission between field and module. Two coding keys prevent incorrect insertion onto mismatched I/O modules. Additionally, four strain relief clips secure incoming cables against vibration and pulling forces.

Energy Storage and Signal Stability

This front connector stores 0.6 joules across two small ceramic capacitors. This minimal storage filters high-frequency noise on field input signals. The capacitors also suppress contact bounce during manual wiring changes. Consequently, the connector provides clean signal transmission without external filtering components.

Parameter	Value	Unit
Dimensions (H x W x D)	120 x 45 x 55	mm
Weight	0.15	kg
Total components	52	pieces
Gold-plated contact pins	20	pins
Coding keys	2	units
Strain relief clips	4	units
Ceramic capacitors	2	units
Total energy storage	0.6	J
Contact rating (per pin)	2	A
Contact resistance	<10	mΩ
Insulation resistance	>100	MΩ
Rated voltage	250	V AC/DC
Mating cycles (minimum)	200	cycles
Operating temperature	-20 to 60	°C
Storage temperature	-40 to 85	°C
Wire gauge range	AWG 24–16	–
Stripping length	7	mm
Screw torque	0.5	Nm

Interface and Connectivity Features

The Siemens 6ES5490-7LA11 provides 20 screw terminals for individual field wires. A 20-pin female receptacle connects directly to the S5 I/O module front. You will also find two cable entry ports for top or bottom wiring access. Each screw terminal accepts AWG 24 to AWG 16 solid or stranded copper wire.

Wiring and Termination Details

You can wire this connector without removing it from the I/O module. The screw terminals use rising cage clamp technology for secure wire retention. Each terminal has a test point for voltage measurement without loosening the wire. Furthermore, the connector includes numbered positions matching the module channel assignments.

Coding and Keying Features

The Siemens 6ES5490-7LA11 includes two removable coding keys for mechanical alignment. You can insert these keys into pre-drilled slots on the connector body. The matching I/O module has corresponding cutouts that accept only properly keyed connectors. This feature prevents you from connecting the wrong wiring harness to a module.

Strain Relief and Cable Management

Four strain relief clips secure incoming cables firmly to the connector body. You can route cables upward or downward depending on your cabinet layout. The clips accommodate round cables up to 12mm diameter without damage. Proper strain relief prevents wire pull-out during maintenance or vibration events.

Diagnostic and Identification Features

The Siemens 6ES5490-7LA11 includes a labeling strip for marking channel assignments. You can insert pre-printed labels or write directly on the strip. The transparent cover protects the label from dirt, oil, and moisture. Additionally, the connector has visible test points for each terminal for probe access.

Compatibility and System Integration

This front connector works with all SIMATIC S5 I/O modules that use 20-pin interfaces. You can use this unit with digital input, digital output, analog input, and analog output modules. The connector supports both 24V DC and 230V AC signal types without modification. Furthermore, the unit fits S5-100U, S5-115U, and S5-135U system families.

Environmental Specifications and Compliance

You can operate this front connector from -20°C to 60°C ambient temperature without derating. Storage temperature ranges from -40°C to 85°C for long-term preservation. The connector’s UL 94 V-0 rated housing resists flame propagation in fault conditions. This unit meets IEC 61131-2 standards for programmable controller I/O connectors.