Siemens 3RB3113-4TB0 SIRIUS Overload Relay, 16 A

Active production — what that means for your BOM line

The 3RB3113-4TB0: It's a SIRIUS solid-state overload relay, Size S00, rated for a thermal current Ith of 16 A at up to 690 V. The solid-state design means no bimetal drift over time, so the trip curve stays consistent across the operating life — relevant for applications where nuisance tripping from thermal aging is a concern.

Trip class adjustability — setting the curve to the load

This relay offers four selectable trip classes: CLASS 5E, 10E, 20E, and 30E. That's the full range from fast-acting (5E, for pumps or compressors that lock rotor quickly) to slow (30E, for high-inertia loads like fans or centrifugals that need a longer start duration without tripping). The adjustment is on the device itself, so you can dial it in during commissioning without swapping hardware. The current setting range is defined by the motor current relative to the upper and lower setting values: the motor current must be greater than the lower setting value and less than the upper setting value multiplied by 3.5. That's a wide window — it means the relay can be set to protect motors with a full-load current anywhere within the adjustment range, with a 3.5× margin on the upper end for starting inrush.

Mounting and panel fit — contactor-mount, no DIN rail needed

Fastening method is contactor mounting — it clips directly onto the Siemens S00 contactor (e.g., 3RT201 or 3RT202 series). No DIN rail required, which saves a slot in a crowded panel. Dimensions: 45 mm wide, 79 mm high, 73 mm deep. Mounting position is any orientation, so no restrictions on vertical vs horizontal placement.

Environmental and compliance — shop floor and regulatory fit

Temperature compensation is built in over the same -25 to +60 °C range, so the trip curve doesn't shift with ambient changes — important for panels near ovens or in unconditioned spaces. Shock resistance is 15 g / 11 ms for the main relay, and 9 g / 11 ms for the signaling contact in the tripped position. Vibration resistance is 1–6 Hz at 15 mm amplitude, 6–500 Hz at 20 m/s², 10 cycles per axis. These ratings mean it holds up on a machine tool or conveyor line without nuisance trips from mechanical shock. Substance prohibitance date is 10/01/2009 — this is the RoHS compliance cutoff for the EU directive. The relay meets RoHS requirements for materials restrictions as of that date.

Auxiliary contact ratings — what the signaling circuit can handle

At 24 VDC, the 2 A rating is enough for most solid-state inputs; at 120 VAC, 4 A handles a contactor coil or indicator lamp directly. Power dissipation per pole is 0.37 W. For a three-pole relay that's about 1.1 W total — negligible heat contribution to the panel, so no derating needed in a standard enclosure.