The Siemens 3RP1540-1BN31 is a SIRIUS time relay with an adjustable delay range of 0.05 to 600 seconds, powered by a 200-240 V supply that accepts both AC (50/60 Hz) and DC. It switches via a relay output rated for a 5 A thermal current, with contact ratings of 1 A at 24 V, 0.2 A at 125 V, and 0.1 A at 250 V. The unit snaps onto a 35 mm DIN rail and accepts stranded wire from 20 to 14 AWG at the screw terminals, torqued to 0.8-1.2 N·m.
The 22.5 mm width (one TE) and 91 mm depth fit neatly into a crowded DIN channel without stealing extra space. Mounting position is unrestricted, so it can go sideways or upside-down in a tight gland-plate layout.
The 0.05-600 s adjustable time covers most industrial timing needs — from a short pulse delay on a conveyor interlock to a longer off-delay for a pump sequence. The 5 A thermal current is the continuous carry rating through the relay contacts; the actual switching capacity depends on voltage (1 A at 24 V, derating to 0.1 A at 250 V). Recovery time of 150 ms means the relay resets quickly between cycles — important for rapid-repeat applications.