Schmersal gear cam limit switches, mainly represented by the G50 and G150 series, are also known as gear-driven cam switches, specially developed for winching and slewing machinery. Equipped with precision built-in gear reduction mechanisms, they convert multiple rotations of the drive shaft into single-cycle cam movement to actuate multi-channel contacts for multi-point signal output. Different from standard straight-stroke limit switches, they accurately calculate rotation cycles and lifting travel via gear ratios, enabling multi-stage position setting including deceleration warning, pre-limit and emergency stop. Selected models feature positive-opening safety contacts to meet functional safety requirements for lifting equipment.
20 mainstream models of Schmersal G50/G150 gear cam limit switches:
G50-017M11/11Y-1600-1
G50-025M44-2281-4/M22Y-1
G50-035M11/11Y-1600-1
G50-035M22/22Y-1600-1-1368-2
G50-050M44/22Y-1368-3
G50-017M22/22Y-1601-4
G50-2047-M22/22Y (Safety version for stage equipment)
G150-075M22-2281-2/M44Y-1
G150-100M44-2281-4/M22Y-1
G150-150M11/11Y
G150-150T22/22Y-1600-1
G150-220M22/22Y-1600-1-1368-2
G150-075T22/22Y-1600-1-1368-3
G50-017M11/11Y-1600-1-1368-4
G50-025T22/22Y-1600-1
G150-100T44/22Y-2281-4
G50-050T22/22Y-FL1
G150-220T44/22Y-1601-1
G50-035T44/22Y-1368-2
G150-075M44/22Y-1601-1
Gear cam limit switches are widely used for rotary and winching equipment across industries: port container cranes, gantry tower cranes, overhead travelling cranes, winch systems, automated parking lifting systems, stage lifting machinery, mining hoisting equipment, metallurgical rotary machines, construction lifting equipment, shield machine auxiliary winches, paper winding machines, rubber & plastic winding machinery, marine deck cranes, material elevators and large lifting platforms. Typical applications include lifting height limitation, trolley travel limiting and slewing angle control. A single unit simultaneously delivers deceleration warning, working limit and emergency protection signals.
Compared with conventional direct-acting limit switches, Schmersal gear cam limit switches feature five core advantages:
First, built-in gear reduction design for multi-turn rotary travel. Multiple gear ratios are available to convert dozens of shaft rotations into effective cam operation. The switches accurately detect wire rope winding cycles and slewing angles, solving the limitation of ordinary switches unable to monitor long-distance winching travel.
Second, multiple independently adjustable cams for synchronous multi-point control. Multiple sets of cam discs can be adjusted in 4° increments. One single switch supports 4~8 contact sets to configure multi-stage positions including deceleration, pre-limit and final stop, reducing the number of components in electrical control systems.
Third, die-cast metal housing ensures stability under harsh environments. Light alloy die-cast housings achieve IP65 protection class, operating steadily from -30℃ to +80℃ with strong resistance to dust, moisture and vibration, suitable for long-term operation of outdoor port and mining machinery. Snap-action and slow-action contacts are optional; high-spec variants adopt positive-opening safety contacts complying with machinery safety standards.
Fourth, diversified connection options for flexible installation. Splined shafts, gear couplings and flange connections are available for direct assembly with reducers and drum shafts. Silver contacts and gold-plated contacts can be selected to drive heavy contactors or transmit low-level electronic signals.
Fifth, passive mechanical design with strong anti-interference performance and complete certifications. Contact signals rely purely on mechanical switching and are immune to electromagnetic interference from inverters. Full-range CE and cULus certifications support equipment export. The robust mechanical structure delivers long service life; commissioning only requires cam angle adjustment for convenient maintenance.
Lifting and rotary machinery feature long travel ranges. Standard limit switches only provide single-point protection and cannot support multi-stage speed control and layered limiting. Featuring gear reduction and multi-channel adjustable cams, Schmersal G50/G150 gear cam limit switches realise multi-point position monitoring within one unit. As core standard components for lifting and rotary equipment, they deliver precise and reliable travel limiting solutions for port, heavy industry and stage special machinery worldwide.
Related Gear Cam Limit Switches
Browse the complete Schmersal Gear Cam Limit Switches range. Representative models available through Glorient:
Safety versions with positive-opening contacts are rated for functional safety circuits. See SIL vs PL Explained for how to determine the required safety level for such applications.
Frequently Asked Questions
What is a gear cam limit switch used for?
It provides precision multi-stroke position control for rotary machinery such as cranes, hoists, stage equipment and wind turbines. Gear-driven cam discs switch at preset angular positions, enabling accurate end-of-travel and multi-position control.
What is the difference between the G50 and G150 series?
The G50 is the compact series for lighter-duty applications, while the G150 is the heavy-duty series with higher switching capacity and larger load ratings. Both offer programmable cam discs for flexible setpoints.
Can gear cam limit switches be used in safety-related applications?
Yes. Safety versions with positive-opening contacts, such as the G50-2047 range, are available for stage equipment and safety-related position monitoring applications.