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.

  • OTDC400UFV11 | ABB 2P 400A Pv Sw 1500Vdc
    ABB

    OTDC400UFV11

    2P 400A Pv Sw 1500Vdc

    $1,286.00
    $1,909.08
  • OTDC400UFV11-ESS | ABB 2P 400A Dc Sw 1500Vdc For Ess App
    ABB

    OTDC400UFV11-ESS

    2P 400A Dc Sw 1500Vdc For Ess App

    $2,270.55
    $5,184.02
  • OTDC400UFV22 | ABB 4P 400A Pv Sw 1500Vdc Wo Jump
    ABB

    OTDC400UFV22

    4P 400A Pv Sw 1500Vdc Wo Jump

    $2,512.53
    $6,216.25
  • OTDC500FV11 | ABB 2P 500A Iec Pv Sw 1500Vdc
    ABB

    OTDC500FV11

    2P 500A Iec Pv Sw 1500Vdc

    $1,431.58
    $3,267.87
  • OTDC600UF02S | ABB 2P 600A Pv Sw 1000Vdc Ul98B Side Op
    ABB

    OTDC600UF02S

    2P 600A Pv Sw 1000Vdc Ul98B Side Op

    $1,402.76
    $3,470.60
  • OTDC600UF11 | ABB 2P 600A Ul Pv 1000Vdc Ds
    ABB

    OTDC600UF11

    2P 600A Ul Pv 1000Vdc Ds

    $1,228.39
    $2,237.78
  • OTDC600UF22 | ABB 4P 600A Pv Sw 1000Vdc
    ABB

    OTDC600UF22

    4P 600A Pv Sw 1000Vdc

    $2,271.55
    $5,620.05
  • OTDC600UFV22 | ABB 4P 600A Ul Pv 1500Vdc Ds
    ABB

    OTDC600UFV22

    4P 600A Ul Pv 1500Vdc Ds

    $2,840.15
    $7,026.85
  • OTDC630F11 | ABB 2P 630A Iec Pv 1000Vdc Ds
    ABB

    OTDC630F11

    2P 630A Iec Pv 1000Vdc Ds

    $1,285.81
    $1,519.35
  • OTDC630FV11-ESS | ABB 2P 630A Dc Sw 1500Vdc For Ess App
    ABB

    OTDC630FV11-ESS

    2P 630A Dc Sw 1500Vdc For Ess App

    $2,600.73
    $3,007.20
  • OTDCB250/2 | ABB Otdc100/180/200 Phase Barriers 2 Ea
    ABB

    OTDCB250/2

    Otdc100/180/200 Phase Barriers 2 Ea

    $10.88
    $18.17
  • OTDCKIT1250B11 | ABB Connection Bar For Otdc800-1000U
    ABB

    OTDCKIT1250B11

    Connection Bar For Otdc800-1000U

    $362.80
    $897.60
  • OTDCKIT400FS101 | ABB Jumper Kit For 2-P Otdc 1500V
    ABB

    OTDCKIT400FS101

    Jumper Kit For 2-P Otdc 1500V

    $143.23
    $354.35
  • OTDCKIT400FS11 | ABB Jumper Kit For 4-P Otdc 1500V
    ABB

    OTDCKIT400FS11

    Jumper Kit For 4-P Otdc 1500V

    $285.71
    $706.87
  • OTDCKIT600FS101 | ABB 600A Kit For 2P Otdc 1500V
    ABB

    OTDCKIT600FS101

    600A Kit For 2P Otdc 1500V

    $238.36
    $542.72
  • OTDCKIT600FS11 | ABB 600A Kit For 4P Otdc 1500V
    ABB

    OTDCKIT600FS11

    600A Kit For 4P Otdc 1500V

    $428.61
    $1,060.42
  • OTDV250EK | ABB Ot200U Direct Mount Handle
    ABB

    OTDV250EK

    Ot200U Direct Mount Handle

    $88.85
    $103.45
  • OTDV400FK1 | ABB Direct Mount Handle For Otdc
    ABB

    OTDV400FK1

    Direct Mount Handle For Otdc

    $97.25
    $149.60
  • OTDV400FK2 | ABB 145Mm Otdc Direct Mount Handle
    ABB

    OTDV400FK2

    145Mm Otdc Direct Mount Handle

    $103.39
    $150.70
  • OTDVY250EK | ABB Ot200U Direct Mount Handle
    ABB

    OTDVY250EK

    Ot200U Direct Mount Handle

    $88.85
    $102.75
  • OTM100F3CMA230V | ABB 3P 100A Motorized Xfer Sw Iec
    ABB

    OTM100F3CMA230V

    3P 100A Motorized Xfer Sw Iec

    $2,252.58
    $3,168.20
  • OTM100F4CMA230V | ABB 4P 100A Auto Transfer Switch
    ABB

    OTM100F4CMA230V

    4P 100A Auto Transfer Switch

    $2,421.35
    $2,799.80
  • OTM1250E3CM230C | ABB Motorized C/O Switch
    ABB

    OTM1250E3CM230C

    Motorized C/O Switch

    $20,381.75
    $48,252.35
  • OTM125F3C21D400C | ABB 3P 125A Auto Transfer Switch
    ABB

    OTM125F3C21D400C

    3P 125A Auto Transfer Switch

    $3,504.56
    $4,052.32
  • OTM125F3CMA230V | ABB 3P 125A Motorized C/O Sw Open Trans
    ABB

    OTM125F3CMA230V

    3P 125A Motorized C/O Sw Open Trans

    $2,961.06
    $4,165.17
  • OTM125F4CMA230V | ABB 4P 100A Auto Transfer Switch
    ABB

    OTM125F4CMA230V

    4P 100A Auto Transfer Switch

    $3,182.81
    $7,267.53
  • OTM125F4CMA24D | ABB 125A 4P Mot C/O Sw Open Trans 24Vdc
    ABB

    OTM125F4CMA24D

    125A 4P Mot C/O Sw Open Trans 24Vdc

    $3,183.43
    $3,730.75
  • OTM1600E3CM110V | ABB 3P 1600A Xf Motor C/O 110Vdc/Ac Iec
    ABB

    OTM1600E3CM110V

    3P 1600A Xf Motor C/O 110Vdc/Ac Iec

    $23,989.31
    $33,422.17

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.