3RT2018-2KB42-0LA0

The original manufacturer designates it as a Contactor for Railway Application. It features a 24V DC coil with a built-in suppressor diode, spring-loaded terminals for PLC output signals, a main circuit rated AC-3 of 16A/7.5kW (400V), and one set of normally closed auxiliary contacts.

Share To

Siemens 3RT2018-2KB42-0LA0 Rail Transit Contactor 24V DC with Built-in Diode Coil AC-3 16A/7.5kW

Product Positioning

The 3RT2018-2KB42-0LA0 is clearly labeled "CONT. F. RAILW. A." in the manufacturer's and distributor's catalogs, indicating it's an S00 miniature contactor specifically designed for railway applications. The coil is 24V DC with a built-in suppression diode, and its operating voltage range is 0.7 to 1.25 times the rated value, capable of withstanding voltage fluctuations common in railway vehicle control power supplies. The spring-loaded terminals are specifically marked "suitable for PLC outputs," meaning its coil drive characteristics are suitable for direct drive by PLC digital output points, reducing the need for additional relay circuitry. The main circuit continues the 3RT2018 family's AC-3 16A/7.5kW (400V) rating, with the model number ending in 42 corresponding to one set of normally closed auxiliary contacts for easy feedback of switch status to the control system.

Core Product Advantages and Features

Rail Transit-Specific Certification Orientation

The original manufacturer's catalog indicates that it is a model specifically designed for railway application and is designed for the control environment of rail vehicles.

Built-in suppression diode

The 24V DC coil has a built-in suppression diode that absorbs the coil's back electromotive force upon power failure, protecting surrounding electronic control components.

PLC output driver adapter

The coil characteristic markings are suitable for direct drive of PLC digital outputs, simplifying control circuit design and reducing the cost of additional drive interfaces.

Wide operating voltage tolerance

The coil can operate stably within a voltage range of 0.7-1.25 times the rated voltage, adapting to fluctuations in the track control power supply voltage.

project	Specification
Product Series	SIRIUS 3RT20, frame size S00
Extreme number	3 poles (3 normally open main contacts)
Application type	Special contactors for rail transit/railway applications
AC-3 Rated Current/Power (400V)	16 A / 7.5 kW
Coil Specifications	24V DC, built-in suppression diode
Coil operating voltage range	0.7 ~ 1.25 × rated voltage
auxiliary contacts	Group 1 normally closed (1NC)
Terminal type	Spring-loaded terminals, compatible with PLC outputs
net weight	Approximately 0.35 kg
Installation method	35 mm DIN rail
Insulation voltage	690 V (Pollution Level 3)
Protection level	IP20 (Front Panel)
Mechanical life	Approximately 30 million times

Recommend

3RT2018-2XF41-0LA2

S00 frame contactor for rail transit, 72-125V DC wide-range electronic coil with built-in surge suppression, spring terminal 1NO auxiliary contacts, main contact rated current 20A, AC-3 operating current 16A/7.5kW, operating temperature -40~70°C

3RT2018-2FB42

S00 frame contactor, spring-loaded terminals for screwless quick-connection, 24V DC coil with built-in suppression diode to reduce power failure surge, equipped with one set of normally closed auxiliary contacts, main circuit AC-3 rated 16A/7.5kW, suitable for motor control and interlocking circuits.

3RT2018-2FB41

Spring terminal S00 contactor, 24V DC coil with built-in diode for suppressing surges, one set of normally open auxiliary contacts for start-up feedback signal, AC-3 rated 16A/7.5kW (400V), storage temperature range -55°C to 80°C.