Siemens 6ES5701-3LA12 Mounting Rack

Technical Specifications and Rack Design

This mounting rack provides mechanical support and backplane connectivity for SIMATIC S5 modules. The Siemens 6ES5701-3LA12 accommodates up to eight I/O modules in a single chassis. You can install this rack inside a standard industrial control cabinet. Its rigid steel construction prevents flexing during module insertion or removal. The rack weighs approximately 2.8 kilograms. Its dimensions measure 30 cm in height, 48 cm in width, and 21 cm in depth.

Parameter	Specification
Brand	Siemens
Model	6ES5701-3LA12
Category	Mounting Rack / Backplane Chassis
Weight	2.8 kg
Height	30 cm
Width	48 cm
Depth	21 cm
Number of Slots	8 slots for S5-115U modules
Slot Spacing	5 cm per slot (standard)
Backplane Type	Passive printed circuit board
Bus Connector Type	48-pin DIN 41612 (female) per slot
Power Bus Capacity	20 Amps at 5V DC, 10 Amps at 24V DC
Mounting Method	4 x M6 threaded holes (rear)
Material	Zinc-coated steel (1.5 mm thickness)
Energy Storage	None (passive component)
Component Count	1 chassis, 1 backplane PCB, 8 slot connectors, 1 power connector

Backplane Architecture and Slot Organization

The passive backplane PCB distributes power and signals to all eight slots. Each slot connects to the system bus through a 48-pin DIN 41612 connector. The Siemens 6ES5701-3LA12 includes a dedicated power input connector on the left side. This connector accepts 24V DC and 5V DC from an external power supply. The backplane uses wide copper traces for low voltage drop. Consequently, all modules receive stable power even at maximum load. Slot 1 typically holds the CPU or interface module. Slots 2 through 8 accommodate I/O and special function modules.

Physical Construction and Durability

The zinc-coated steel chassis resists corrosion in industrial environments. Four M6 threaded holes on the rear panel secure the rack to a mounting plate. The Siemens 6ES5701-3LA12 includes card guides for each slot position. These guides align modules correctly during insertion to prevent pin damage. A removable cover plate protects the backplane during shipping or storage. The rack can support fully populated modules without sagging or distortion. The operating temperature ranges from 0°C to 60°C.

Installation and Grounding Guidelines

You must mount this rack on a flat, grounded metal surface for proper shielding. The chassis connects to protective earth through the mounting screws. The Siemens 6ES5701-3LA12 requires at least 10 cm clearance above and below. This clearance allows proper airflow around the installed modules. You should install filler plates in any empty slots for dust protection. The rack does not include any electronic components or active circuitry. Therefore, it requires no configuration or addressing before use.