NEMA 3 Switches | McMaster-Carr

Filter by

Actuator Style

System of Measurement

Switching Current

Switching Voltage

Switch Position

Switch Starting Position

Switch Type

Push-Button Style

Actuator Color

Switch Action

Number of Circuits Controlled

Certification

Switch Designation

Enclosure Rating

DFARS Compliance

Panel Cutout Diameter

Wire Connection

Environment

Actuator Material

Reset Type

Number of Terminals

Housing Material

Mounting Hole Diameter

Forward

How can we improve?

70 Products

Choosing an Electrical Switch

About Pressure Switches

30 mm Emergency Stop Panel-Mount Push-Button Switches

Immediately cut power with a single push. These switches are rated for protection from low-pressure streams of water and oil/coolant spraying. They have positive force contacts that will open a circuit when actuated even if a spring fails or the contacts stick. Switches include enough contact blocks to control the number of circuits listed.

Turn twist switches back on by twisting the button and pull switches by pulling it. Add an optional lockout on either kind to cover the button and prevent changes its position.

Note: Illuminated switches include a bulb. If wiring the switch and the bulb to the same circuit, the circuit voltage must not exceed bulb voltage.

Additional contact blocks (sold separately) can be added to control more circuits, or to replace the included contact block.

Pull Reset

Twist Reset

Illuminated Pull Reset

Metal Base with Screw Terminals
No. of Circuits Controlled	Switch Starting Position	Switch Action	No. of Terminals	Industry Designation	Actuator Color	Switching Current @ Voltage	Max. Voltage	Dia.	Dp. Behind Panel	For Max. No. of Contact Blocks	Choose a Bulb Voltage		Each
Pull Reset
1	1 On (Normally Closed)	Stays Switched (Maintained)	2	SPST-NC	Red	6 A @ 120 V AC, 5 A @ 24 V DC	250V DC 600V AC	1 1/2"	1 1/2"	8	__	00000000	000000
2	1 Off (Normally Open) and 1 On (Normally Closed)	Stays Switched (Maintained)	4	DPST-1NO/1NC	Red	6 A @ 120 V AC, 5 A @ 24 V DC	250V DC 600V AC	1 1/2"	1 1/2"	8	__	00000000	000000
2	2 On (Normally Closed)	Stays Switched (Maintained)	4	DPST-NC	Red	6 A @ 120 V AC, 5 A @ 24 V DC	250V DC 600V AC	1 1/2"	1 1/2"	8	__	00000000	000000
Twist Reset
1	1 On (Normally Closed)	Stays Switched (Maintained)	2	SPST-NC	Red	6 A @ 120 V AC, 5 A @ 24 V DC	250V DC 600V AC	1 1/2"	1 1/2"	8	__	00000000	000000
2	1 Off (Normally Open) and 1 On (Normally Closed)	Stays Switched (Maintained)	4	DPST-1NO/1NC	Red	6 A @ 120 V AC, 5 A @ 24 V DC	250V DC 600V AC	1 1/2"	1 1/2"	8	__	00000000	000000
2	2 On (Normally Closed)	Stays Switched (Maintained)	4	DPST-NC	Red	6 A @ 120 V AC, 5 A @ 24 V DC	250V DC 600V AC	1 1/2"	1 1/2"	8	__	00000000	000000
Metal Base with Screw Terminals—Illuminated
Pull Reset
1	1 Off (Normally Open)	Stays Switched (Maintained)	4	SPST-NO	Red	6 A @ 120 V AC, 5 A @ 24 V DC	250V DC 600V AC	1 1/2"	2 1/16"	4	24V AC/24V DC, 120V AC/120V DC	0000000	000000
1	1 On (Normally Closed)	Stays Switched (Maintained)	4	SPST-NC	Red	6 A @ 120 V AC, 5 A @ 24 V DC	250V DC 600V AC	1 1/2"	2 1/16"	4	240V AC/240V DC	00000000	000000
2	1 Off (Normally Open) and 1 On (Normally Closed)	Stays Switched (Maintained)	6	DPST-1NO/1NC	Red	6 A @ 120 V AC, 5 A @ 24 V DC	250V DC 600V AC	1 1/2"	2 15/16"	4	24V AC/24V DC, 120V AC/120V DC, 240V AC/240V DC	0000000	000000
2	2 On (Normally Closed)	Stays Switched (Maintained)	6	DPST-NC	Red	6 A @ 120 V AC, 5 A @ 24 V DC	250V DC 600V AC	1 1/2"	2 15/16"	4	24V AC/24V DC, 120V AC/120V DC, 240V AC/240V DC	0000000	000000
Plastic Base with Screw Terminals
Pull Reset
1	1 On (Normally Closed)	Stays Switched (Maintained)	2	SPST-NC	Red	6 A @ 120 V AC, 5 A @ 24 V DC	250V DC 600V AC	1 1/2"	1 1/2"	8	__	00000000	00000
2	1 Off (Normally Open) and 1 On (Normally Closed)	Stays Switched (Maintained)	4	DPST-1NO/1NC	Red	6 A @ 120 V AC, 5 A @ 24 V DC	250V DC 600V AC	1 1/2"	1 1/2"	8	__	00000000	000000
Twist Reset
1	1 On (Normally Closed)	Stays Switched (Maintained)	2	SPST-NC	Red	6 A @ 120 V AC, 5 A @ 24 V DC	250V DC 600V AC	1 1/2"	1 1/2"	8	__	00000000	00000
2	1 Off (Normally Open) and 1 On (Normally Closed)	Stays Switched (Maintained)	4	DPST-1NO/1NC	Red	6 A @ 120 V AC, 5 A @ 24 V DC	250V DC 600V AC	1 1/2"	1 1/2"	8	__	00000000	000000
2	2 On (Normally Closed)	Stays Switched (Maintained)	4	DPST-NC	Red	6 A @ 120 V AC, 5 A @ 24 V DC	250V DC 600V AC	1 1/2"	1 1/2"	8	__	00000000	000000

Contact Blocks

For 1 1/2" Diameter Switches
No. of Circuits Controlled	Switch Starting Position	No. of Terminals	Industry Designation		Each
1	1 Off (Normally Open)	2	SPST-NO	00000000	000000
1	1 On (Normally Closed)	2	SPST-NC	00000000	00000

Replacement Actuators for 1 1/2" Diameter Switches

					Pull Reset		Twist Reset
Actuator Clarity	Actuator Color	Bulb Type	Bulb Color	Choose a Bulb Voltage		Each		Each
Metal Base—Not Illuminated
Opaque	Red	__	__	__	00000000	000000	00000000	000000
Metal Base—Illuminated
Clear	Red	LED	Red	24V AC/24V DC, 120V AC/120V DC, 240V AC/240V DC	0000000	000000	000000	00
Plastic Base—Not Illuminated
Opaque	Red	__	__	__	00000000	00000	00000000	00000

Replacement Bulbs for Pull Reset Switches

Replacement Bulb

	Bulb
Voltage	Shape Number	Diameter	Overall Length	Bulb Material	Color	Light Technology	Rated Life, hrs.		Each
For 1 1/2" Diameter Switches
For Switches with 24V AC/24V DC Bulb
24V AC, 24V DC	T3 1/4	3/8"	1 1/8"	Plastic	Red	LED	100,000	00000000	000000
For Switches with 120V AC/120V DC Bulb
130V AC, 130V DC	T3 1/4	3/8"	1 1/8"	Plastic	Red	LED	100,000	00000000	00000

Optional Lockouts for 1/2" Diameter Switches

For Maximum Padlock Shackle Diameter		Each
1/4"	00000000	000000

Hazardous Location Enclosed Push-Button Switches

One Mushroom Button

One Flush Button

One Flush Button and One Projecting Button

Use these switches where ignitable gas and dust may be present. They're rated for use in hazardous locations.

For technical drawings and 3-D models, click on a part number.

									Mounting
Message (Actuator Color)	No. of Circuits Controlled per Button	Switch Starting Position	Switch Action	No. of Terminals per Button	Industry Designation	Switching Current @ Voltage	Max. Voltage	Conduit Trade Size	Fasteners Included	No. of Holes	Hole Dia.		Each
With Screw Terminals
1 Mushroom Button
Stop (Red)	1	1 Off (Normally Open) and 1 On (Normally Closed)	Stays Switched (Maintained)	4	DPST-1NO/1NC	10 A @ 120 V AC	600V AC	3/4	No	2	3/16"	0000000	0000000
1 Flush Button
Start (Black)	1	1 Off (Normally Open) and 1 On (Normally Closed)	Springs Back (Momentary)	4	DPST-1NO/1NC	10 A @ 120 V AC	600V AC	3/4	No	2	5/16"	0000000	000000
1 Flush Button and 1 Projecting Button
Start (Green), Stop (Red)	2	1 Off (Normally Open) and 1 On (Normally Closed)	Springs Back (Momentary)	2	DPST-1NO/1NC	10 A @ 120 V AC	600V AC	3/4	No	2	9/32"	0000000	000000

Hazardous Location Enclosed Lever Switches

Use these switches where ignitable gas, dust, and fibers may be present. They're UL and C-UL listed for hazardous locations.

For technical drawings and 3-D models, click on a part number.

									Mounting
Actuator Color	Message (Switch Position)	No. of Circuits Controlled	Switch Starting Position	Switch Action	No. of Terminals	Industry Designation	Switching Current @ Voltage	Max. Voltage	Fasteners Included	No. of Holes	Hole Dia.		Each
3 Positions
With Screw Terminals
Gray	Hand (Left), Off (Center), Auto (Right)	2	1 Off (Normally Open) and 1 On (Normally Closed)	Stays Switched (Maintained)	4	DPST-1NO/1NC	10 A @ 120 V AC	600V AC	No	2	5/16"	0000000	0000000

Enclosed Disconnect Switches

Cut power and keep it isolated to prevent equipment from starting up during inspection and maintenance. These switches are housed in a protective enclosure.

Switches with lockout secure in the off position with a padlock with a maximum shackle diameter of 5/16” (not included).

Add auxiliary contact blocks to send a signal or connect to another device, such as an alarm or indicating light.

Use additional power poles to control more than three circuits. Add neutral poles to open and close the neutral leg of a three phase system.

For technical drawings and 3-D models, click on a part number.

Three-Circuit Switch

Three-Circuit Switch with Lockout

Switching
Current, A	Voltage	Industry Designation	Electrical Phase (hp)	Ht.	Wd.	Environmental Rating		Each
Plastic Housing with Red Actuator
Stays Switched (Maintained)
3 Circuits
50	600V AC	3PST	Single (1 1/2 hp @ 120 V AC) Single (3 hp @ 240 V AC) Three (7 1/2 hp @ 240 V AC)	8 11/16"	5 7/8"	IP40, NEMA 3	00000000	0000000
63	600V AC	3PST	Single (3 hp @ 120 V AC) Single (5 hp @ 240 V AC) Three (10 hp @ 240 V AC)	8 11/16"	5 7/8"	IP40, NEMA 3	00000000	000000
80	600V AC	3PST	Single (3 hp @ 120 V AC) Single (10 hp @ 240 V AC) Three (20 hp @ 240 V AC)	8 11/16"	5 7/8"	IP40, NEMA 3	00000000	000000
100	600V AC	3PST	Single (5 hp @ 120 V AC) Single (10 hp @ 240 V AC) Three (25 hp @ 240 V AC)	8 11/16"	5 7/8"	IP40, NEMA 3	00000000	000000
3 Circuits with Lockout
50	600V AC	3PST	Single (1 1/2 hp @ 120 V AC) Single (3 hp @ 240 V AC) Three (7 1/2 hp @ 240 V AC)	8 11/16"	5 7/8"	IP40, NEMA 3	00000000	000000
63	600V AC	3PST	Single (3 hp @ 120 V AC) Single (5 hp @ 240 V AC) Three (10 hp @ 240 V AC)	8 11/16"	5 7/8"	IP40, NEMA 3	00000000	000000
80	600V AC	3PST	Single (3 hp @ 120 V AC) Single (10 hp @ 240 V AC) Three (20 hp @ 240 V AC)	8 11/16"	5 7/8"	IP40, NEMA 3	00000000	000000
100	600V AC	3PST	Single (5 hp @ 120 V AC) Single (10 hp @ 240 V AC) Three (25 hp @ 240 V AC)	8 11/16"	5 7/8"	IP40, NEMA 3	00000000	000000
Plastic Housing with Gray Actuator
Stays Switched (Maintained)
3 Circuits
50	600V AC	3PST	Single (1 1/2 hp @ 120 V AC) Single (3 hp @ 240 V AC) Three (7 1/2 hp @ 240 V AC)	8 11/16"	5 7/8"	IP40, NEMA 3	00000000	000000
63	600V AC	3PST	Single (3 hp @ 120 V AC) Single (5 hp @ 240 V AC) Three (10 hp @ 240 V AC)	8 11/16"	5 7/8"	IP40, NEMA 3	00000000	000000
80	600V AC	3PST	Single (3 hp @ 120 V AC) Single (10 hp @ 240 V AC) Three (20 hp @ 240 V AC)	8 11/16"	5 7/8"	IP40, NEMA 3	00000000	000000
100	600V AC	3PST	Single (5 hp @ 120 V AC) Single (10 hp @ 240 V AC) Three (25 hp @ 240 V AC)	8 11/16"	5 7/8"	IP40, NEMA 3	00000000	000000
3 Circuits with Lockout
50	600V AC	3PST	Single (1 1/2 hp @ 120 V AC) Single (3 hp @ 240 V AC) Three (7 1/2 hp @ 240 V AC)	8 11/16"	5 7/8"	IP40, NEMA 3	00000000	000000
63	600V AC	3PST	Single (3 hp @ 120 V AC) Single (5 hp @ 240 V AC) Three (10 hp @ 240 V AC)	8 11/16"	5 7/8"	IP40, NEMA 3	00000000	000000
80	600V AC	3PST	Single (3 hp @ 120 V AC) Single (10 hp @ 240 V AC) Three (20 hp @ 240 V AC)	8 11/16"	5 7/8"	IP40, NEMA 3	00000000	000000
100	600V AC	3PST	Single (5 hp @ 120 V AC) Single (10 hp @ 240 V AC) Three (25 hp @ 240 V AC)	8 11/16"	5 7/8"	IP40, NEMA 3	00000000	000000

"Main Switch" Label with Adhesive Back—13/16" Ht. × 3 3/16" Wd.

0000000

Each

000000

Replacement Actuator for 3 Circuit Switches with Lockout

				Plastic Housing with Red Actuator
For Switching Current	Ht.	Wd.	Dp.		Each
25A, 32A, 50A, 63A	2 9/16"	2 9/16"	1 5/16"	0000000	000000
80A, 100A	3 3/8"	3 3/8"	1 5/16"	0000000	00000

Auxiliary Contact Block for 3 Circuit Switches

Switching Current, A		Each
10	0000000	000000

Additional Power Poles for 3 Circuit Switches

Switching Current, A	Specifications Met		Each
50	UL Listed, CE Marked	00000000	000000
63	UL Listed, CE Marked	00000000	00000
80	UL Listed, CE Marked	00000000	00000
100	UL Listed, CE Marked	00000000	00000

Neutral Poles for 3 Circuit Switches

Switching Current, A	Specifications Met		Each
50	UL Listed, CE Marked	00000000	000000
63	UL Listed, CE Marked	00000000	00000
80	UL Listed, CE Marked	00000000	00000
100	UL Listed, CE Marked	00000000	00000

Junction Blocks for 3 Circuit Switches

For Current, A	Specifications Met		Each
50/63	UL Listed, CE Marked	00000000	000000
80/100	UL Listed, CE Marked	00000000	00000

Hazardous Location Differential Pressure Switches for Air

With an explosionproof enclosure that meets NEMA 7 and 9 standards for hazardous locations, these switches were tested and verified by UL and CSA for use where explosive gas or dust may be present. Often used with ovens, dryers, and HVAC systems, they can indicate a filter is clogged or help maintain a certain air pressure. These switches turn equipment on and off, activate automated controls, or signal alarms when the differential pressure reaches your setpoint. They are single pole, double throw (SPDT) and can be installed to turn one circuit from off to on (normally open) or from on to off (normally closed).

In addition to being UL listed and CSA certified, these switches are CE marked and FM approved, so they also meet European safety standards. They also are IP and NEMA rated for use outdoors and protect against dust and splashing water.

When measuring pressure in ductwork, pair them with a static pressure probe.

For technical drawings and 3-D models, click on a part number.

Screw Terminals
Setpoint Range	Approximate Difference Between Setpoint and Reset Point	Max. Input Pressure	Accuracy	Max. Switching Current	Process Temp. Range, °F	Connection Material	For Use With	Environmental Rating		Each
1/8 NPT Female Pipe Connection
0.07-0.15 in. of H2O	0.13 in. of H2O	45 in. of H2O	±2%	15 A @ 125 V AC 15 A @ 250 V AC 15 A @ 480 V AC	-40° to 140°	Aluminum	Air	IP54; NEC Class I Divisions 1, 2 Groups C, D; NEC Class II Division 1 Groups E, F ,G; NEMA 3; NEMA 7; NEMA 9	0000000	0000000
0.15-0.5 in. of H2O	0.05 in. of H2O	45 in. of H2O	±2%	15 A @ 125 V AC 15 A @ 250 V AC 15 A @ 480 V AC	-40° to 140°	Aluminum	Air	IP54; NEC Class I Divisions 1, 2 Groups C, D; NEC Class II Division 1 Groups E, F ,G; NEMA 3; NEMA 7; NEMA 9	0000000	000000
0.4-1.6 in. of H2O	0.18 in. of H2O	45 in. of H2O	±2%	15 A @ 125 V AC 15 A @ 250 V AC 15 A @ 480 V AC	-40° to 140°	Aluminum	Air	IP54; NEC Class I Divisions 1, 2 Groups C, D; NEC Class II Division 1 Groups E, F ,G; NEMA 3; NEMA 7; NEMA 9	0000000	000000
1.4-5.5 in. of H2O	0.35 in. of H2O	45 in. of H2O	±2%	15 A @ 125 V AC 15 A @ 250 V AC 15 A @ 480 V AC	-40° to 140°	Aluminum	Air	IP54; NEC Class I Divisions 1, 2 Groups C, D; NEC Class II Division 1 Groups E, F ,G; NEMA 3; NEMA 7; NEMA 9	0000000	000000
3-11 in. of H2O	0.45 in. of H2O	45 in. of H2O	±2%	15 A @ 125 V AC 15 A @ 250 V AC 15 A @ 480 V AC	-40° to 140°	Aluminum	Air	IP54; NEC Class I Divisions 1, 2 Groups C, D; NEC Class II Division 1 Groups E, F ,G; NEMA 3; NEMA 7; NEMA 9	0000000	000000
4-20 in. of H2O	0.5 in. of H2O	45 in. of H2O	±2%	15 A @ 125 V AC 15 A @ 250 V AC 15 A @ 480 V AC	-40° to 140°	Aluminum	Air	IP54; NEC Class I Divisions 1, 2 Groups C, D; NEC Class II Division 1 Groups E, F ,G; NEMA 3; NEMA 7; NEMA 9	0000000	000000
0.5-2 psi	0.3 psi	35 psi	±2%	15 A @ 125 V AC 15 A @ 250 V AC 15 A @ 480 V AC	-40° to 140°	Aluminum	Air	IP54; NEC Class I Divisions 1, 2 Groups C, D; NEC Class II Division 1 Groups E, F ,G; NEMA 3; NEMA 7; NEMA 9	0000000	000000
1.5-8 psi	1 psi	35 psi	±2%	15 A @ 125 V AC 15 A @ 250 V AC 15 A @ 480 V AC	0° to 140°	Aluminum	Air	IP54; NEC Class I Divisions 1, 2 Groups C, D; NEC Class II Division 1 Groups E, F ,G; NEMA 3; NEMA 7; NEMA 9	0000000	000000
3-15 psi	0.9 psi	35 psi	±2%	15 A @ 125 V AC 15 A @ 250 V AC 15 A @ 480 V AC	0° to 140°	Aluminum	Air	IP54; NEC Class I Divisions 1, 2 Groups C, D; NEC Class II Division 1 Groups E, F ,G; NEMA 3; NEMA 7; NEMA 9	0000000	000000
4-25 psi	0.7 psi	35 psi	±2%	15 A @ 125 V AC 15 A @ 250 V AC 15 A @ 480 V AC	0° to 140°	Aluminum	Air	IP54; NEC Class I Divisions 1, 2 Groups C, D; NEC Class II Division 1 Groups E, F ,G; NEMA 3; NEMA 7; NEMA 9	0000000	000000
15-50 psi	1.25 psi	70 psi	±2%	15 A @ 125 V AC 15 A @ 250 V AC 15 A @ 480 V AC	0° to 140°	Aluminum	Air	IP54; NEC Class I Divisions 1, 2 Groups C, D; NEC Class II Division 1 Groups E, F ,G; NEMA 3; NEMA 7; NEMA 9	0000000	000000