The S8M-CP04-RS is a DIN-rail mounted multicircuit protector from Omron's S8M series, combining overcurrent, overtemperature, overvoltage, and undervoltage protection in one unit. It accepts a 24VDC supply and trips across a range of 0.5mA to 3.8A with a voltage window of 18.0 to 28.8VDC, making it a single-point safeguard for sensitive RS-232 communication circuits and low-power control loops.
Why the trip range matters
The 0.5mA lower limit catches leakage faults that a standard breaker would ignore — critical when you're protecting a 24V serial link where a few milliamps of ground fault can corrupt data or drift a sensor reading. The 3.8A upper end covers most small relays, solenoids, and indicator loads you'd find in a control cabinet. If your load pulls more than that, this isn't the protector for that circuit.
Mounting and termination
Snaps onto standard 35mm DIN rail — no drilling, no backplate. Screw terminals accept 0.2–2.5 mm² solid or stranded wire; strip 8 mm to avoid stray whiskers under the clamp. Rated for -10°C to 60°C ambient, so it lives in a ventilated panel, not a hot enclosure corner.