SIRIUS 3RU2146-4FB0 — thermal overload relay, S3 frame, CLASS 10
Rated for 18.5 kW at 400 V (AC-3e) and 40 A at 480 V, this relay covers a solid mid-range motor band. The 690 V rated insulation voltage means it's suitable for 400 V and 480 V line supplies with headroom, but not for 690 V line-to-line systems — the 37 kW at 690 V figure applies only when the relay's contacts are switching that voltage level, not the motor's line supply. Mounts directly onto a contactor (fastening method: contactor mounting,) in any position. The screw-type main terminals accept solid 2× (2.5…16 mm²) or stranded up to 1× 70 mm², which covers common motor cable sizes for this frame. Integrated auxiliary switch provides the tripped signal — the relay carries a note "for message 'Tripped'", meaning the auxiliary contact changes state on overload, not on manual test or reset.
RoHS compliance date is noted as 03/01/2017, confirming the part meets the EU RoHS substance restrictions effective from that date. The relay also carries the SIRIUS brand's standard CE marking for the European market.
These figures make it suitable for unheated enclosure installations in temperate climates, but not for extended exposure above 70 °C ambient. The 4 mm hexagon socket screwdriver shaft is required for the screw terminals. Depth of 125 mm, width 70 mm, height 105 mm — fits standard S3 contactor footprints. Panel builders should note the M8 main contact screw size when selecting lug rings for motor cables.