Siemens 3RT2028-1AP04 SIRIUS Power Contactor 3P 38A 18.5kW 230V AC

The Siemens 3RT2028-1AP04 is a SIRIUS 3RT2 series power contactor rated at 38 A and 18.5 kW at 400 V, designed for AC-3/AC-3e motor switching duties. It features a 3-pole main circuit with a 230 V AC / 50 Hz control coil and an integrated auxiliary contact arrangement of 2 NO + 2 NC. Connections are made via screw terminals in size S0 housing with a removable auxiliary switch.

Technical specifications:

• MLFB: 3RT2028-1AP04
• Manufacturer: Siemens
• Product line: SIRIUS
• Product type: Power contactor (3RT2)
• Contactor size: S0
• Number of main poles: 3
• Rated operational current (AC-3, 400 V): 38 A
• Rated operational current (AC-1, 400 V, 40°C): 50 A
• Rated power (AC-3, 400 V): 18.5 kW
• Rated power (AC-3, 230 V): 11 kW
• Control supply voltage: 230 V AC, 50 Hz
• Auxiliary contacts: 2 NO + 2 NC
• Terminal type: Screw terminal
• Insulation voltage (main and auxiliary circuit): 690 V
• Surge voltage resistance: 6 kV
• Operating temperature: -25 ... +60°C
• Storage temperature: -55 ... +80°C
• Max. installation altitude: 2000 m
• Mechanical service life: 10,000,000 operating cycles
• No-load switching frequency (AC): 5000 /h
• Net weight: 0.463 g

Features and benefits:

• Removable auxiliary switch block allows flexible field configuration of contact arrangement
• Wide ambient temperature range (-25 ... +60°C) suits demanding industrial environments
• High mechanical service life of 10,000,000 cycles reduces maintenance intervals
• Rated for AC-3e duty alongside standard AC-3, supporting extended motor control applications
• Surge voltage resistance of 6 kV on both main and auxiliary circuits provides protection against transient overvoltages

Applications:

• Direct-on-line starting and switching of three-phase motors up to 18.5 kW at 400 V
• Motor control centers and industrial switchgear panels
• Pump, fan, and compressor control in building services and process plants
• AC-4 reversing or jogging duty at reduced current ratings

Compliant with EN/IEC 60947-4-1 for contactors and motor starters. Part of the Siemens SIRIUS 3RT2 range.

Also known as: Siemens 3RT2028-1AP04, SIRIUS 3RT2 power contactor 38A, Siemens S0 contactor 230V AC.