McMaster-Carr logo
    Filter by
    Actuator Style
    Switch Designation
    Key Included
    Wire Connection
    Input Voltage
    Industrial Info Snippet
    Number of Terminals
    Conduit Thread Type
    Industrial Info Compare
    Key Entry
    Housing Material
    Enclosure Rating
    Industrial Info Compare
    Number of Circuits Controlled
    Switch Action
    Industrial Info Compare
    Material
    DFARS Specialty Metals
    Gender
    Thread Type
    Industrial Info Compare
    U.S.–Mexico–Canada Agreement (USMCA) Qualifying
    Conduit Connection Gender
    Export Control Classification Number (ECCN)
    Industrial Info Snippet
    Enter e-mail addresses in the fields below
    Message
    Cancel
    Comments
    E-mail address (if you would like a response)
    21 Products

    Frame-Mounted Safety Switches

    Image of ProductInUse. Key Shown Actuating from the Side. Front orientation. Safety Switches. Frame-Mounted Safety Switches.
    Image of Product. Front orientation. Safety Switches. Frame-Mounted Safety Switches, Style C.
    Image of Product. Front orientation. Safety Switches. Frame-Mounted Safety Switches, Style D.
    Image of Product. Front orientation. Safety Switches. Frame-Mounted Safety Switches, Style G.

    Key Shown Actuating from the Side

    Style C

    Style D

    Style G

    Also known as interlock switches, these ensure the safety of personnel by automatically shutting off power to machinery when an access door opens. Mount the switch to the door frame and mount a key to the door so that the key is inserted into the switch when the door is closed. When the door opens, the key is removed from the switch and the machine shuts down. They’re often used with machine guards for large robots.
    Styles C-G—Style A-G switches have positive-force, normally closed contacts that will open a circuit when the switch is actuated even if a spring fails or the contacts stick.
    IP67 Enclosure Rating—IP67 rated switches protect against temporary submersion.
    Key Included—All switches require an actuator key, but not all include one—check whether you need to pick out a separate actuator key. For some switch styles, you can also select the mounting orientation of the key.
    Housing
    Conduit
    Style
    No. of Circuits
    Controlled
    Switch Starting
    Position
    Switch
    Action
    No. of
    Terminals
    Switch
    Designation
    Switching Current @ Voltage
    Max. Voltage
    Ht.
    Wd.
    Dp.
    Trade
    Size
    Thread
    Size
    Thread
    Type
    Key
    Included
    Enclosure
    Rating
    Each
    Screw-Terminal Wire Connection with Positive-Force Normally Closed Contacts
    C31 Off and 2 On
    Maintained
    33PST-1NO/2NC
    8 amp @ 120V AC, 4 amp @ 24V DC600V AC
    250V DC
    3.5"2.1"1.2"1/2
    NPT
    YesIP67
    000000000000000
    C31 Off and 2 On
    Maintained
    63PST-1NO/2NC
    4 amp @ 230V AC, 4 amp @ 24V DC500V AC
    24V DC
    3.5"2"1.2"M16
    Metric
    YesIP67
    00000000000000
    D31 Off and 2 On
    Maintained
    63PST-1NO/2NC
    6 amp @ 120V AC, 0.27 amp @ 24V DC240V AC
    250V DC
    3.8"1.2"1.2"1/2
    NPT
    YesIP67
    0000000000000
     
    Screw-Terminal Wire Connection with Positive-Force Normally Closed Contacts and Rotating Head
    C31 Off and 2 On
    Maintained
    63PST-1NO/2NC
    5 amp @ 120V AC, 5 amp @ 24V DC400V AC
    400V DC
    3.5"2"1.3"1/2
    NPT
    YesIP65
    00000000000000
    D31 Off and 2 On
    Maintained
    63PST-1NO/2NC
    10 amp @ 120V AC, 2.5 amp @ 125V DC240V AC
    250V DC
    3.8"1.2"1.2"M20
    Metric
    NoIP67
    0000000000000
    G31 Off and 2 On
    Maintained
    63PST-1NO/2NC
    10 amp @ 230V AC, 4 amp @ 24V DC250V AC
    24V DC
    4.3"1.6"1.4"M20
    Metric
    NoIP67
    00000000000000
     
    Actuator Keys

    Build-Your-Own Limit Switches

    Combine an actuator and a switch to assemble the exact limit switch you need. These switches have the rapid-closing action of a snap-acting switch, but have a larger actuator for large objects. When an object in motion comes into contact with the actuator, it sends a signal to open or close a circuit. They’re often used for conveyor systems and elevators. Each actuator style is compatible with all housing styles and vice versa.
    Switches
    Image of Product. Front orientation. Limit Switches. Build-Your-Own Limit Switches, Switches, Screw Terminal Connection—LED Power Indicator and LED Status Indicator.

    Screw Terminal

    Connection—LED

    Power

    Indicator and

    LED Status

    Indicator

    Polypropylene Housing—Switches with a polypropylene housing are lighter in weight than metal switches.
    LED Power Indicator and LED Status Indicator—Switches with an LED power indicator and LED status indicator show you the status of the line and load phases. They give you extra assurance that your switch is connected and wired correctly.
    IP65 Enclosure Rating—IP65 switches protect against dust and splashing water.
    IP66 Enclosure Rating—IP66 switches protect against dust and washdowns.
    IP67 Enclosure Rating—IP67 switches protect against dust and temporary submersion.
    Housing
    Conduit
    No. of Circuits
    Controlled
    Switch Starting
    Position
    Switch
    Action
    Switch
    Designation
    Switching Current
    @ Voltage
    Max. Voltage,
    V DC
    No. of
    Terminals
    Lg.
    Ht.
    Dp.
    No. of
    Connections
    Thread
    Size
    Enclosure
    Rating
    Specs.
    Met
    Certification
    Each
    Polypropylene Housing
     
    Screw Terminal Connection—LED Power Indicator and LED Status Indicator
    31 Off and 2 On
    Momentary
    3PST-1NO/2NC
    3 amp @ 24V DC2461.2"2.7"1.3"1M20
    IP65
    EN 50047UL Listed, C-UL Listed, CE Marked, CCC Marked
    00000000000000
    31 Off and 2 On
    Momentary
    3PST-1NO/2NC
    3 amp @ 24V DC2461.6"3.1"1.5"1M20
    IP66, IP67
    EN 50041UL Listed, C-UL Listed, CE Marked, CCC Marked
    0000000000000
     

    Hinge-Actuated Safety Switches

    Image of ProductInUse. Front orientation. Contains Border. Safety Switches. Hinge-Actuated Safety Switches.
    Image of Product. Front orientation. Safety Switches. Hinge-Actuated Safety Switches.
    Replace the hinges on access doors or machine guards with these switches to keep your team safe from active machinery. Also known as interlock switches, they automatically shut off power to your machinery when the door or guard opens. They can be mounted on flat frames or aluminum T-slotted framing. These switches have positive-force, normally-closed contacts that will open a circuit when the switch is actuated, even if a spring fails or the contacts stick. They’re rated IP65 for protection from washdowns.
    Overall
    For Rail
    Ht., mm
    Mounting Hole Ctr.-to-Ctr.
    Wd., mm
    Switch
    Action
    No. of
    Terminals
    Switch
    Designation
    Switching Current
    @ Voltage
    Wire
    Connection
    Conduit Thread
    Size
    Ht.
    Wd.
    Dp.
    Each
    3 Circuits Controlled—1 Off and 2 On
     
    4° Actuation Angle—Aluminum Hinge
    3034Momentary
    63PST-1NO/2NC
    2 amp @ 230V ACScrew TerminalM20
    5.2"4.39"1.42"000000000000000
    3539Momentary
    63PST-1NO/2NC
    2 amp @ 230V ACScrew TerminalM20
    5.2"4.39"1.42"00000000000000
    4044Momentary
    63PST-1NO/2NC
    2 amp @ 230V ACScrew TerminalM20
    3.62"4.39"1.42"0000000000000
    4549Momentary
    63PST-1NO/2NC
    2 amp @ 230V ACScrew TerminalM20
    5.2"4.39"1.42"00000000000000
     
    4° Actuation Angle—Stainless Steel Hinge
    4044Momentary
    63PST-1NO/2NC
    2 amp @ 230V ACScrew TerminalM20
    3.62"4.39"1.42"00000000000000
     
    8° Actuation Angle—Aluminum Hinge
    4044Momentary
    63PST-1NO/2NC
    2 amp @ 230V ACScrew TerminalM20
    3.62"4.39"1.42"00000000000000
     

    Access-Delay Frame-Mounted Safety Switches

    Image of ProductInUse. Key Shown Actuating from the Side. Front orientation. Safety Switches. Access-Delay Frame-Mounted Safety Switches.

    Key Shown Actuating from the Side

    Image of Product. Front orientation. Safety Switches. Access-Delay Frame-Mounted Safety Switches, Style A.

    Style A

    Image of Product. Front orientation. Safety Switches. Access-Delay Frame-Mounted Safety Switches, Style B.

    Style B

    Delay access to hazardous areas until conditions are safe; use these switches with machines that take time to stop after they are turned off. Mount the switch to the door frame and mount the key to the door so that the key is inserted into the switch when the door is closed. When the door is pulled, the key is held in place with 225 lbs. of force until the switch receives a signal from a time-delay relay, motion sensor, or position sensor (not included) that the machine’s motion has stopped. After the motion has stopped, the key can be removed from the switch, releasing the access door. They’re often used with machine guards. All have positive-force, normally-closed contacts that will open a circuit when the switch is actuated even if a spring fails or the contacts stick. They’re rated for protection from washdowns and temporary submersion.
    Styles A and B—Style A and B have a key entry on the top and side of the switch.
    Housing
    Conduit
    Style
    No. of Circuits
    Controlled
    Switch Starting
    Position
    Switch
    Action
    No. of
    Terminals
    Switch
    Designation
    Switching Current @ Voltage
    Max. Voltage
    Input Voltage
    Holding
    Force, lbf
    Ht.
    Wd.
    Dp.
    Trade
    Size
    Thread
    Type
    Enclosure
    Rating
    Each
    Screw-Terminal Wire Connection with Positive-Force Normally Closed Contacts
    A31 Off and 2 On
    Maintained
    63PST-1NO/2NC
    5 amp @ 120V AC, 2 amp @ 24V DC500V AC
    250V DC
    24V AC, 24V DC2254.7"2.3"1.4"1/2
    NPT
    IP67, NEMA 6
    00000000000000
    A31 Off and 2 On
    Maintained
    63PST-1NO/2NC
    5 amp @ 120V AC, 2 amp @ 24V DC500V AC
    250V DC
    110V AC2254.7"2.3"1.4"1/2
    NPT
    IP67, NEMA 6
    0000000000000
    B31 Off and 2 On
    Maintained
    143PST-1NO/2NC
    3 amp @ 120V AC, 2.5 amp @ 24V DC240V AC
    250V DC
    24V DC2253.7"3.5"1.4"1/2
    NPT
    IP67
    0000000000000
     
    Keys
    back to top