What it is and what it does
The Siemens 3RT1916-2DH11 is a SIRIUS timing relay — a single-function OFF-delay relay with an adjustable time range of 0.05 … 1 s. It is designed for control circuits where a load must stay energised for a set period after the control signal drops out, typical in conveyor sequencing, pump run-on, or ventilation after-stop timing. The control supply accepts 90 … 240 V AC (50/60 Hz) or DC, so it works across common line voltages without a separate power supply module. The relay clips onto a DIN rail (clip-on mounting) and can be installed in any orientation, which simplifies panel layout.
Key ratings and what they mean for fit
The adjustable OFF-delay spans 0.05 … 1 s, set via a potentiometer or DIP switch (the evidence does not specify the adjustment method). The minimum ON period before the delay can start is 35 ms, and after the delay expires the relay needs 150 ms recovery time before it can trigger again — important for fast-cycling loads like short conveyor segments. The terminal enclosure carries IP20 protection, meaning it is protected against solid objects larger than 12.5 mm (fingers) but not against moisture — standard for a DIN-rail component inside a closed control panel. Pollution degree 3 (conductive pollution or dry non-conductive pollution that becomes conductive due to condensation) means it is rated for industrial environments where the panel is not sealed against humidity. Basic insulation per IEC 61812-1 and EMC immunity to EN 61000-6-2 confirm it meets the minimum isolation and noise-rejection requirements for industrial control circuits. Maximum operating altitude is 2 000 m, which covers most installations except high-altitude mining or mountain-top sites.