Monostable push-button switch NC LP400 412909

Manual circuit control in a compact modular housing

The LP400 series monostable NC push-button switch is an actuator designed for the manual switching on and off of electrical circuits. Unlike bistable solutions - the normally closed (NC) contact opens only when the button is pressed, and automatically returns to its original position upon release. This mechanism is ideal anywhere where control must be momentary and directly dependent on the operator's decision.

The device occupies one module on the TS-35 DIN rail (width 17.8 mm), allowing for efficient space management in distribution boards. The housing is made of halogen-free plastic - important in installations where limiting the emission of toxic gases in case of fire is required.

Construction and mounting

The button is grey (RAL 7035) and is adapted for mounting on a standard TH35 DIN rail. The installation depth is 44 mm, which means compatibility with most surface-mounted and flush-mounted distribution boards found in industrial and building installations.

The screw terminals accept wires with a cross-section from 0.75 to 4 mm² - a range sufficient for both flexible conductors and single-core wires used in stationary installations. Each terminal is marked, facilitating correct connection without the need to guess the contact function. The device is also equipped with a labeling window, allowing for permanent marking of the button function during commissioning or maintenance.

Electrical parameters and operating conditions

The normally closed (NC) contact handles a load of 20 A at 250 V AC, allowing for direct control of moderate-power loads without the need for intermediate relays. The AC-12 utilization category includes controlling resistive and low-voltage electronic loads - a typical application in building and industrial automation.

A rated impulse withstand voltage of 4 kV and an insulation voltage of 500 V demonstrate resistance to surges occurring in standard network installations. The operating temperature range from −25 to +70 °C makes the button suitable for both heated rooms and cooler technical spaces - e.g., boiler rooms or warehouses.

The housing provides an IP20 protection rating, which means protection against finger access and solid objects >12.5 mm. The device is not intended for exposure to moisture or dust - therefore, it is mounted inside distribution boards.

Standards and certificates

The product meets the requirements of the IEC/EN 60669-1 standard regarding switches for electrical devices. It is compatible with fluorescent loads up to 20 AX, which is important when controlling luminaires with electronic ballasts - these generate high inrush currents that exceed the capabilities of ordinary buttons.

Quality is confirmed by OC/CB certificates and the NF certificate issued by the French standardization institution - documents available in the manufacturer's database for those implementing projects requiring formal verification of compliance.