Industrial MS4320B Light Curtain Receiver/Transmitter Sensor

STI MS4320B Minisafe-B light curtain receiver, 20 inches long, is the receiver component of STI's Minisafe-B safety-light-curtain family designed for industrial machine guarding. The MS4320B-2 variant operates on 115 VAC at 50/60 Hz and draws about 0.25 A, with a response time under 35 ms to detect beam interruptions quickly. Manufactured in the United States, this 20-inch (0.51 m) module is sold individually and represents the standard Minisafe-B receiver form factor used in STI beam-curtain configurations. As part of a complete safety-light-curtain setup, it is paired with a corresponding transmitter to monitor access openings and trigger protective actions when a beam is broken. The compact, long 20-inch design and straightforward electrical requirements make it suitable for guarding medium-length machine perimeters in automated environments, including booths and presses, where rapid detection of intrusion is critical.