Fusible and Non-Fusible Disconnect Switches

What Is a Disconnect Switch

A disconnect switch is a manually operated device that completely isolates electrical equipment from its power source, letting you de-energize a circuit safely for maintenance, inspection, repair, or emergency shutdown. It creates a visible, verifiable break in the circuit. Unlike electronic switching, the physical separation of contacts confirms that no current can reach downstream equipment. The National Electrical Code requires disconnect switches for motor-driven equipment, and they must be installed within sight of the equipment they isolate.

Wistex supplies disconnect switches built to meet OSHA lock-out/tag-out requirements while providing safe, reliable isolation for industrial equipment. Choose from fusible, non-fusible, and motor disconnect options up to 2000 A, all available in NEMA 4X and NEMA 12 enclosures for harsh or dusty environments. With rapid shipping and expert guidance, Wistex ensures you get the right switch for the job. Need overcurrent protection? Pair your switch with one of our circuit breakers.

  • OSZT1L | ABB On/Off Mech Intlk Os200
    ABB

    OSZT1L

    On/Off Mech Intlk Os200

    $412.21
    $485.93
  • OSZT2A | ABB Off Mech Intlk Os400
    ABB

    OSZT2A

    Off Mech Intlk Os400

    $460.63
    $532.62
  • OSZT2L | ABB Off/On Mech Intlk Os400
    ABB

    OSZT2L

    Off/On Mech Intlk Os400

    $460.63
    $916.25
  • OSZT3A | ABB Off Mech Intlk Os600
    ABB

    OSZT3A

    Off Mech Intlk Os600

    $533.19
    $721.97
  • OSZT3L | ABB Off/On Mech Intlk Os600
    ABB

    OSZT3L

    Off/On Mech Intlk Os600

    $533.19
    $1,266.33
  • OSZT4A | ABB Off Mech Intlk Os1200
    ABB

    OSZT4A

    Off Mech Intlk Os1200

    $604.93
    $875.17
  • OSZT4L | ABB Off/On Mech Intlk Os1200
    ABB

    OSZT4L

    Off/On Mech Intlk Os1200

    $604.93
    $699.47
  • OT1000E04 | ABB 4P Sw 1000A Nf 690V Iec
    ABB

    OT1000E04

    4P Sw 1000A Nf 690V Iec

    $9,859.86
    $13,735.87
  • OT1000E22 | ABB 4P Ot Sw 1000A Iec
    ABB

    OT1000E22

    4P Ot Sw 1000A Iec

    $9,859.86
    $13,380.00
  • OT100F3 | ABB Switch Nf 3P 100A Ul98
    ABB

    OT100F3

    Switch Nf 3P 100A Ul98

    $179.36
    $266.26
  • OT100F3/B25 | ABB 3P Sw Nf 100A Bulk Pack 25
    ABB

    OT100F3/B25

    3P Sw Nf 100A Bulk Pack 25

    $3,564.66
    $5,291.77
  • OT100F3C | ABB 3P Xfer Sw 100A Nf Ul98
    ABB

    OT100F3C

    3P Xfer Sw 100A Nf Ul98

    $460.94
    $684.26
  • OT100F3U | ABB 3P Sw 100A Nf Metal Collar
    ABB

    OT100F3U

    3P Sw 100A Nf Metal Collar

    $399.63
    $488.13
  • OT100FD8 | ABB 75A 600Vdc Rated Disc Sw
    ABB

    OT100FD8

    75A 600Vdc Rated Disc Sw

    $508.64
    $729.25
  • OT100FT4N2 | ABB 4P 100A Ul508 Nf Door Mount Sw
    ABB

    OT100FT4N2

    4P 100A Ul508 Nf Door Mount Sw

    $250.21
    $371.44
  • OT1200U02 | ABB 2P Sw 1200A Nf 600V Ul98
    ABB

    OT1200U02

    2P Sw 1200A Nf 600V Ul98

    $5,560.15
    $10,134.95
  • OT1200U03 | ABB 3P Sw 1200A Nf 600V Ul98
    ABB

    OT1200U03

    3P Sw 1200A Nf 600V Ul98

    $6,878.54
    $10,211.22
  • OT1200U04 | ABB 4P Sw 1200A Nf 600V Ul98
    ABB

    OT1200U04

    4P Sw 1200A Nf 600V Ul98

    $8,175.20
    $20,226.33
  • OT1200U12 | ABB 3P Sw 1200A Nf Ul98
    ABB

    OT1200U12

    3P Sw 1200A Nf Ul98

    $6,878.73
    $9,334.03
  • OT1200U22 | ABB 4P Sw 1200A Nf Ul98
    ABB

    OT1200U22

    4P Sw 1200A Nf Ul98

    $7,712.45
    $9,121.52
  • OT1200U30 | ABB 3P Sw 1200A Nf 600V Ul98
    ABB

    OT1200U30

    3P Sw 1200A Nf 600V Ul98

    $6,878.73
    $8,135.27
  • OT1200U30-FC | ABB 3P Sw 1200A Nf Flange Cable Mech
    ABB

    OT1200U30-FC

    3P Sw 1200A Nf Flange Cable Mech

    $6,939.23
    $10,301.32
  • OT1250E03 | ABB Switch-Disconnector
    ABB

    OT1250E03

    Switch-Disconnector

    $8,250.89
    $20,413.57
  • OT1250E03C | ABB 3P 1250A Ul98 Manual Xfer Sw
    ABB

    OT1250E03C

    3P 1250A Ul98 Manual Xfer Sw

    $13,900.35
    $16,441.25
  • OT1250E04 | ABB 4P Sw 1250A Nf 690V Iec
    ABB

    OT1250E04

    4P Sw 1250A Nf 690V Iec

    $9,901.18
    $24,496.57
  • OT1250E04C | ABB 4P Dt Nf Sw 1250A Iec
    ABB

    OT1250E04C

    4P Dt Nf Sw 1250A Iec

    $15,568.90
    $18,002.30
  • OT1250E11 | ABB 2P Sw 1250A Nf 690V Iec
    ABB

    OT1250E11

    2P Sw 1250A Nf 690V Iec

    $7,539.63
    $15,023.10
  • OT1250E12C | ABB 3P 1250A Iec Manual Xfer Sw
    ABB

    OT1250E12C

    3P 1250A Iec Manual Xfer Sw

    $13,900.66
    $16,441.63

Fusible vs Non-Fusible Disconnect Switches

Fusible disconnect switches combine circuit isolation with overcurrent protection in a single device. Fuses are built into the switch mechanism, so the switch both isolates the circuit for maintenance and clears short circuits and overloads automatically. Non-fusible disconnect switches provide isolation only and rely on upstream devices, such as circuit breakers or motor starters, for overcurrent protection. A fusible switch is typically specified where short-circuit protection is needed at the point of service, such as at a service entrance or in high fault-current applications. Non-fusible switches are the more economical choice where overcurrent protection is already handled upstream, and are commonly used for motor leads. Wistex fusible switches accept Class J, R, and H fuses.

Disconnect Switches We Offer

Our selection includes trusted brands and enclosure styles to suit virtually any industrial application.

Fusible Safety Switches

Fusible Safety Switches

Fusible disconnects provide short-circuit protection and meet NEC service entrance requirements. Ideal for high SCCR applications, these NF-rated switches accept a variety of fuse classes, including J, R, and H.

Non-Fusible Disconnects

Compact and economical, non-fusible disconnect switches offer a reliable means to manually isolate equipment for maintenance. These are commonly used for motor loads when protection is handled upstream.

Non-Fusible Disconnects
Enclosed Motor Disconnects

Enclosed Motor Disconnects

These all-in-one motor disconnects combine a switch and enclosure, making them ideal for local servicing points on rooftop units, pump panels, or machinery.

Lock-Out/Tag-Out Compliance

Disconnect switches support lock-out/tag-out procedures through padlockable handles that can be secured in the OFF position, preventing accidental re-energisation while maintenance is underway. Clear ON and OFF position indication allows anyone approaching the equipment to confirm its state without opening the enclosure.

Applications for Disconnect Switches

Wistex disconnects are field-proven across a wide range of industrial and commercial systems.

  • HVAC units
  • Machine tools
  • Pump panels
  • Rooftop equipment

Complete your motor control system with contactors and soft starters.

Why Choose Wistex for Safety Disconnects

Wistex is trusted for code-compliant solutions that meet real-world demands. We stock a wide range of fusible and non-fusible disconnect switches, with amperages from 30 A to 2000 A, and enclosure options built for your environment. Our experts can help you build out complete solutions with fuse kits, mounting hardware, and made-in-USA selections, all ready to ship fast.

Disconnect Switch FAQs

Need help choosing or sizing a disconnect switch? Start with these commonly asked questions.

A fusible disconnect switch is typically required when short-circuit protection is needed at the point of service, such as service entrances or fault-current applications. Many local codes also specify fusing for added safety.

To size a switch, multiply your motor's Full Load Amps (FLA) by 115%, consider voltage and phase, and select the correct fuse class. Browse our 30A disconnect switch options or filter by amperage to find your match.

A disconnect switch provides a safe means to isolate power, but unlike a circuit breaker, it does not offer overcurrent protection. Disconnects are ideal for lock-out/tag-out compliance and scheduled maintenance.