Siemens 5TT5802-0 SENTRON Insta Contactor — 230 V AC, 2 NC, 18 mm
The Siemens 5TT5802-0 is a SENTRON Insta contactor with two normally-closed (NC) contacts, rated for 230 V AC operating voltage and designed to switch incandescent lamp loads up to 1000 W.
The 230 V AC coil is the only voltage variant on this unit — it's not a dual-voltage or DC coil, so the control circuit must be 230 V line-to-neutral or line-to-line. The 2 NC contact arrangement (no NO contacts) means this contactor is normally closed when the coil is de-energized; it opens when the coil is powered. That's the opposite of a standard lighting contactor, so it's suited for fail-safe circuits where the load should stay on unless the control signal is actively applied — emergency lighting override circuits, for example. The 1000 W incandescent lamp load rating is the switching capacity for that specific load type. For other load types (resistive, inductive) you'd need to derate per the manufacturer's data — the 1000 W figure is not a universal contact rating. Power loss is 1.7 W per pole in hot operating state, which is modest but relevant for thermal buildup in a tightly packed enclosure. The installation note explicitly requires spacers between units for heat dissipation — do not butt these up against each other on the DIN rail without the specified air gap.
Typical applications include switching lighting circuits, heating loads, or other 230 V AC single-phase loads where a compact NC contactor is required. The single-module width (18 mm) saves rail space compared to multi-pole contactors, making it a good fit for retrofit or expansion in panels where every millimeter counts.