Siemens 5TT5833-0 SENTRON Insta Contactor — 25 A, 4 NC, 230 V AC Coil
The contactor coil is rated for 230 V AC. This is a 2-module-width unit (36 mm wide) with an IP20 protection class, intended for installation in distribution boards or control panels where normally-closed switching is required.
The 25 A AC rated operational current is the continuous current the main contacts can carry in AC-1 duty (resistive load). For motor or inductive loads, derating applies per the manufacturer's data. The 230 V AC coil voltage must match the control circuit supply; a 24 V DC coil variant would be a different order code. The 440 V maximum operating voltage sets the ceiling for the line voltage the contacts can safely switch — this contactor is suitable for 230/400 V three-phase systems where the line-to-line voltage does not exceed 440 V. The four NC contacts are closed when the coil is de-energized. This configuration is typically used for fail-safe circuits (e.g., holding an emergency-stop loop) or for loads that must be normally powered when the contactor is off. With zero NO contacts, this part cannot be used for a standard motor start/stop where the main power contacts are NO.
Installation and Panel Integration
The manufacturer explicitly notes that spacers must be provided between adjacent devices to ensure adequate heat dissipation — this is not optional; omitting spacers can cause thermal tripping or contact welding at full rated current.