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Bad Wolf Surge Protection Devices

Surge Protectors

Browse Bad Wolf AC and DC surge protection devices by voltage, electrical system, surge current rating, and connection style. Choose from residential, commercial, industrial, marine, vehicle, battery, and equipment protection solutions.

Installing surge protection at a main breaker panel? A Type 1 SPD can also be installed in compatible Type 2 load-side locations. Type 1 gives you more installation flexibility because it can be used at the service entrance or on the load side of the service disconnect.
UNDERSTANDING SPD TYPES

Type 1 vs. Type 2 Surge Protectors

If you were told to install a Type 2 surge protector at your main breaker panel, you can also use a properly applied Type 1 SPD in that location. The difference is primarily where each SPD type is permitted to be installed.

Important: A Type 1 SPD can be installed at the service entrance or in compatible load-side locations where a Type 2 SPD would normally be installed. A Type 2 SPD is intended for load-side installation and is not used on the line side of the service disconnect.
TYPE 1

Most Installation Flexibility

Type 1 SPDs can be installed at the electrical service entrance or on the load side of the service disconnect.

  • Service entrance applications
  • Main breaker panels
  • Compatible subpanel applications
  • Can be used in Type 2 installation locations
TYPE 1 CAN ALSO SERVE TYPE 2 LOCATIONS
TYPE 2

Load-Side Installation

Type 2 SPDs are installed on the load side of the service disconnect, such as at a main breaker panel or compatible downstream panel.

  • Main breaker panels
  • Distribution panels
  • Compatible subpanels
  • Not intended for line-side service-entrance installation
TYPE 3

Point-of-Use Protection

Type 3 SPDs provide an additional layer of protection close to the equipment being protected.

  • Plug-in surge protectors
  • Receptacle or equipment-level protection
  • Used downstream from the electrical service
  • Complements whole-building surge protection
Shopping for a whole-house SPD? Do not rule out a Bad Wolf product simply because it is labeled Type 1. A Type 1 SPD can also be installed in compatible Type 2 locations when installed according to its listing, instructions, and applicable electrical codes.
Browse by Specification

Choose by Voltage & Electrical System

Start by selecting the voltage and electrical system you need to protect. For most U.S. homes with standard 120/240V electrical service, choose 120/240V Split Phase.

MOST U.S. HOMES Looking for whole-house or main-panel surge protection?

Start with our 120/240V split-phase surge protectors for typical residential electrical systems.

View 120/240V Home SPDs

AC Surge Protectors

For AC power systems including residential split-phase, single-phase, low-voltage control circuits, and three-phase systems.

Were you told to install a Type 2 SPD at your main breaker panel? A properly applied Type 1 SPD can also be installed in compatible Type 2 load-side locations.

DC Surge Protectors

For DC battery, vehicle, marine, off-grid, solar, MC4, equipment, NMEA 2000, and specialty DC systems.

120/240V Whole-House Surge Capacity

Already know the surge capacity you are looking for? Use these shortcuts to jump directly to the corresponding 120/240V split-phase whole-house products.

AC Surge Protectors

AC Surge Protection Devices

Bad Wolf AC surge protection devices are organized below by voltage and electrical system. Start with the system voltage, then compare surge current capacity, SPD type, and mounting style.

120/240V Split Phase

120/240V Split-Phase AC Surge Protectors

For standard 120/240V split-phase electrical systems commonly used in U.S. homes, light commercial buildings, generator systems, workshops, farms, and other compatible applications.

Back to AC Section
Shopping for a Type 2 surge protector for your main breaker panel? Most Bad Wolf whole-house models below are Type 1 SPDs. A Type 1 SPD can also be installed in compatible Type 2 load-side locations, giving you the flexibility to use it at a main panel while retaining its Type 1 service-entrance capability.
PANEL MOUNT

Panel-mount models use a built-in 1/2-inch NPT male connection for direct mounting to a compatible electrical panel or enclosure.

LIQUID-TIGHT

Liquid-tight models use a 1/2-inch liquid-tight connector for installations where the SPD is mounted separately from the electrical panel.

RIGID CONDUIT

The HSD240V and PHSD240V are designed to accept 1/2-inch rigid plastic conduit inserted into the enclosure connection. These connections are not threaded and do not use a liquid-tight fitting.

50kA LIQUID-TIGHT

SP240V50KA

Type 1 SPD · Also Suitable for Type 2 Locations

  • 50kA surge current capacity
  • 120/240V split-phase systems
  • 1/2-inch liquid-tight connection
View Product
50kA PANEL MOUNT

SP240V50KA-A

Type 1 SPD · Also Suitable for Type 2 Locations

  • 50kA surge current capacity
  • 120/240V split-phase systems
  • 1/2-inch NPT direct panel mount
View Product
65kA LIQUID-TIGHT

SP240V65KA

Type 1 SPD · Also Suitable for Type 2 Locations

  • 65kA surge current capacity
  • 120/240V split-phase systems
  • Compact whole-house protection
View Product
100kA PANEL MOUNT

SP240V100KA-A

Type 1 SPD · Also Suitable for Type 2 Locations

  • 100kA surge current capacity
  • Six-mode surge protection
  • 1/2-inch NPT direct panel mount
View Product
100kA LIQUID-TIGHT

SP240V100KA-B

Type 1 SPD · Also Suitable for Type 2 Locations

  • 100kA surge current capacity
  • Six-mode surge protection
  • 1/2-inch liquid-tight connection
View Product
185kA TYPE 2 ONLY

SP240V185KA

Type 2 SPD · Load-Side Installation Only

  • 185kA surge current capacity
  • Installs inside a compatible electrical panel
  • Remote protection-status display
Unlike the Type 1 models: this SPD is intended for load-side Type 2 installation.
View Product
200kA LIQUID-TIGHT

SP240V200KA

Type 1 SPD · Also Suitable for Type 2 Locations

  • 200kA surge current capacity
  • Heavy-duty split-phase protection
  • 1/2-inch liquid-tight connection
View Product
200kA PANEL MOUNT

SP240V200KA-A

Type 1 SPD · Also Suitable for Type 2 Locations

  • 200kA surge current capacity
  • Heavy-duty split-phase protection
  • 1/2-inch NPT direct panel mount
View Product
225kA LIQUID-TIGHT

SP240V225KA

Type 1 SPD · Also Suitable for Type 2 Locations

  • 225kA surge current capacity
  • EMP-related surge protection
  • 1/2-inch liquid-tight connection
View Product
225kA PANEL MOUNT

SP240V225KA-A

Type 1 SPD · Also Suitable for Type 2 Locations

  • 225kA surge current capacity
  • EMP-related surge protection
  • 1/2-inch NPT direct panel mount
View Product
260kA RIGID CONDUIT

HSD240V

Type 1 SPD · Also Suitable for Type 2 Locations

  • 260kA surge current capacity
  • EMP-related surge protection
  • Accepts 1/2-inch rigid plastic conduit
View Product
260kA PANEL MOUNT

HSD240V-A

Type 1 SPD · Also Suitable for Type 2 Locations

  • 260kA surge current capacity
  • EMP-related surge protection
  • 1/2-inch NPT direct panel mount
View Product
400kA LIQUID-TIGHT

SP240V400KA

Type 1 SPD · Also Suitable for Type 2 Locations

  • 400kA surge current capacity
  • EMP-related surge protection
  • 1/2-inch liquid-tight connection
View Product
400kA PANEL MOUNT

SP240V400KA-A

Type 1 SPD · Also Suitable for Type 2 Locations

  • 400kA surge current capacity
  • EMP-related surge protection
  • 1/2-inch NPT direct panel mount
View Product
520kA RIGID CONDUIT

PHSD240V

Type 1 SPD · Also Suitable for Type 2 Locations

  • 520kA surge current capacity
  • EMP-related surge protection
  • Accepts 1/2-inch rigid plastic conduit
View Product
520kA PANEL MOUNT

PHSD240V-A

Type 1 SPD · Also Suitable for Type 2 Locations

  • 520kA surge current capacity
  • EMP-related surge protection
  • 1/2-inch NPT direct panel mount
View Product
120V AC

120V AC Surge Protectors

For 120V AC applications including standard household outlets, portable generators, shore power, RV power, equipment, and point-of-use protection. Choose the product that matches your voltage, amperage, and connector style.

Back to AC Section
STANDARD 120V / 15A

For compatible standard grounded 120V outlets using NEMA 5-15 connections.

120V / 30A L5-30

For compatible 30 amp generator, marine shore-power, and equipment applications using L5-30 connections.

120V / 30A RV

For compatible 30 amp RV power connections using TT-30 plug and receptacle configurations.

65kA NEMA 5-15

SP120V65KA

120V 15A Plug-In Surge Protector

  • 65kA surge current capacity
  • 120VAC, 15 amp applications
  • Standard grounded NEMA 5-15 connection
View Product
50kA NEMA 5-15

PSP120V

Portable 120V Type 3 Surge Protector

  • 50kA surge current capacity
  • 120VAC, 15 amp applications
  • 3-foot inline cord for flexible placement
View Product
120kA NEMA 5-15

SSP120V

Spot 120V Type 3 Surge Protector

  • 120kA surge current capacity
  • 120VAC, 15 amp applications
  • Compact direct plug-in design
View Product
80kA L5-30

SP120V80KAL530

120V 30A L5-30 Shore Power Surge Protector

  • 80kA surge current capacity
  • 120VAC, 30 amp applications
  • L5-30 shore power and generator connections
View Product
110kA L5-30

SP120V110KAL30

120V 30A L5-30 Type 3 Surge Protector

  • 110kA surge current capacity
  • 120VAC, 30 amp applications
  • Digital voltmeter and polarity indication
View Product
110kA TT-30

SP120V110KARV

120V 30A RV Type 3 Surge Protector

  • 110kA surge current capacity
  • 120VAC, 30 amp RV applications
  • TT-30 plug and receptacle connections
View Product
24VAC Control Circuits

24VAC Control Circuit Surge Protectors

Protect sensitive 24VAC control wiring used with HVAC thermostats, control boards, air handlers, condensers, relays, and other low-voltage control equipment. Choose between protection for one 24VAC circuit pair or two separate 24VAC circuit pairs.

Back to AC Section
ONE 24VAC CIRCUIT PAIR SP24AA

Choose this model when you need surge protection for one 24VAC control circuit pair.

TWO 24VAC CIRCUIT PAIRS SP24A24AA

Choose this model when you need surge protection for two separate 24VAC control circuit pairs.

24VAC 1 PAIR

SP24AA

24VAC Single-Pair Control Circuit Surge Protector

  • Protects one 24VAC control circuit pair
  • Designed for sensitive low-voltage control wiring
  • Ideal for HVAC controls, thermostats, relays, and control boards
View Product
24VAC 2 PAIRS

SP24A24AA

24VAC Two-Pair Control Circuit Surge Protector

  • Protects two separate 24VAC control circuit pairs
  • Designed for sensitive low-voltage control wiring
  • Useful where multiple 24VAC control circuits need protection
View Product
Installer note: These products are specifically for low-voltage 24VAC control wiring. They do not replace surge protection for the equipment's line-voltage power circuit. Where line-voltage surge protection is also required, select an appropriately rated AC SPD for that electrical system.
Three-Phase AC

Three-Phase AC Surge Protectors

For commercial and industrial three-phase electrical systems. Select the surge protector that matches both the system voltage and the electrical configuration. Wye, open-delta/high-leg, and standard delta systems are not interchangeable.

Back to AC Section
3-PHASE WYE · 3P4W

Choose the wye model that matches your system: 208Y/120V or 480Y/277V. These systems use three phase conductors plus neutral.

240V OPEN DELTA / HIGH LEG · 3P4W

The 3POD240V is specifically designed for compatible 240V three-phase open-delta/high-leg systems.

480V DELTA · 3P3W

The 3PD480V is designed for compatible 480V three-phase delta systems using a 3-phase, 3-wire configuration.

Important: Three-phase surge protectors must be matched to the actual electrical service configuration. Verify system voltage, wye or delta configuration, neutral requirements, and product suitability before installation.
260kA TYPE 2

SP3P208VY

208Y/120V Three-Phase Wye · 3P4W

  • 260kA surge current capacity
  • 208Y/120V three-phase, 4-wire wye systems
  • LED protection-status indication for each phase
View Product
260kA TYPE 2

SP3P480VY

480Y/277V Three-Phase Wye · 3P4W

  • 260kA surge current capacity
  • 480Y/277V three-phase, 4-wire wye systems
  • LED protection-status indication for each phase
View Product
260kA TYPE 2

3POD240V

240V Three-Phase Open Delta / High Leg · 3P4W

  • 260kA surge current capacity
  • 240V open-delta / high-leg three-phase systems
  • LED protection-status indication for each phase
View Product
260kA TYPE 2

3PD480V

480V Three-Phase Delta · 3P3W

  • 260kA surge current capacity
  • 480V three-phase, 3-wire delta systems
  • LED protection-status indication for each phase
View Product
Selection note: Do not select a three-phase SPD based on voltage alone. Confirm the electrical system configuration before choosing a model. For example, a 240V open-delta/high-leg system and a standard delta system require different consideration even though both may be described as three-phase power.
DC Surge Protectors

DC Surge Protection Devices

Bad Wolf DC surge protection devices are organized below by DC voltage and product type. Start with the system voltage, then compare surge current capacity, connection style, and application requirements.

12V DC

12V DC Surge Protectors

For compatible 12V DC battery systems used in vehicles, generators, RVs, marine equipment, emergency power, off-grid systems, solar applications, and other low-voltage DC equipment.

Back to DC Section
12V systems only: The products in this section are designed for compatible 12V DC electrical systems. Do not select a 12V model for a 24V, 36V, 48V, or other higher-voltage DC system.
DIRECT BATTERY CONNECTION

Ring-terminal models connect directly to a compatible 12V battery or DC electrical circuit.

TEST-BUTTON VERSION

The MEMPT12V provides the same 150kA Mini EMP protection with a test button for checking the status indicators when needed.

SAE QUICK CONNECT

The MEMP12VSAE uses an SAE-style connector for convenient connection and removal on compatible 12V systems.

MC4 CONNECTION

The MEMP12VMC4 uses MC4 connectors for compatible 12V solar and MC4-connected DC applications.

150kA RING TERMINAL

MEMP12V

12V DC Mini EMP / Surge Protector

  • 150kA surge current capacity
  • 12V DC battery and electrical systems
  • Two-wire ring-terminal connection
View Product
150kA TEST BUTTON

MEMPT12V

12V DC Mini EMP Protector with Test Button

  • 150kA surge current capacity
  • Ring-terminal connection
  • Test button activates status indicators when needed
View Product
150kA SAE

MEMP12VSAE

12V DC Mini EMP Protector with SAE Connection

  • 150kA surge current capacity
  • 12V DC battery systems
  • SAE-style quick-connect configuration
View Product
150kA MC4

MEMP12VMC4

12V DC Mini EMP Protector with MC4 Connections

  • 150kA surge current capacity
  • Designed for compatible 12V solar/DC systems
  • Plug-and-play MC4 connection style
View Product
250kA RING TERMINAL

12VEMP250KA

12V DC 250kA EMP / Surge Protector

  • 250kA surge current capacity
  • Higher-capacity 12V DC protection
  • Ring-terminal battery connection
View Product
Selection note: First confirm that the electrical system is 12V DC. Then choose the protection capacity and connection style that best matches the installation. Marine NMEA 2000 network products are listed separately in the NMEA 2000 / Marine DC section.
24V–76.8V DC

24V–76.8V DC Surge Protectors

For compatible 24V, 36V, 48V, 60V, 72V, and 76.8V DC battery electrical systems. Select the surge protector that matches the actual nominal system voltage before comparing protection capacity and connection style.

Back to DC Section
Match the SPD to the DC system voltage: These models are voltage-specific. A 24V, 36V, 48V, 60V, 72V, or 76.8V model should only be used on a compatible electrical system within that product's specified voltage rating.
24V MINI EMP SERIES MEMP24V / MEMP24VMC4

Compact protection for compatible 24V DC systems. Choose between a standard battery connection or an MC4-connected version.

500kA MAX EMP SERIES 24V through 76.8V

High-capacity 500kA surge protection for compatible battery systems. Select the MAXEMP model that exactly matches the system voltage.

24V DC BATTERY

MEMP24V

24V DC Mini EMP / Surge Protector

  • Designed specifically for 24V DC systems
  • Compact battery-system surge protection
  • Vehicle, marine, equipment, and emergency power applications
View Product
24V DC MC4

MEMP24VMC4

24V DC Mini EMP Protector with MC4 Connections

  • Designed specifically for 24V DC systems
  • MC4 connection configuration
  • Solar, off-grid, and compatible MC4-connected applications
View Product
500kA 24V DC

MAXEMP24V

MAX EMP 24V DC Surge Protector

  • 500kA surge current capacity
  • For 24V DC battery electrical systems
  • Heavy-duty ring-terminal connection
View Product
500kA 36V DC

MAXEMP36V

MAX EMP 36V DC Surge Protector

  • 500kA surge current capacity
  • For 36V DC battery electrical systems
  • Heavy-duty ring-terminal connection
View Product
500kA 48V DC

MAXEMP48V

MAX EMP 48V DC Surge Protector

  • 500kA surge current capacity
  • For 48V DC battery electrical systems
  • Heavy-duty ring-terminal connection
View Product
500kA 60V DC

MAXEMP60V

MAX EMP 60V DC Surge Protector

  • 500kA surge current capacity
  • For 60V DC battery electrical systems
  • Heavy-duty ring-terminal connection
View Product
500kA 72V DC

MAXEMP72V

MAX EMP 72V DC Surge Protector

  • 500kA surge current capacity
  • For 72V DC battery electrical systems
  • Heavy-duty ring-terminal connection
View Product
500kA 76.8V DC

MAXEMP76.8V

MAX EMP 76.8V DC Surge Protector

  • 500kA surge current capacity
  • For 76.8V DC battery electrical systems
  • Heavy-duty ring-terminal connection
View Product
Selection note: DC system voltage is the first consideration when choosing one of these products. Select the model specifically designed for the battery or DC electrical system being protected. Do not substitute a lower-voltage model on a higher-voltage system.
MAXDC 15V–600V DC

MAXDC DC Surge Protectors

The Bad Wolf MAXDC series provides high-capacity surge protection for a wide range of DC electrical systems from 15V through 600V. Select the MAXDC model that matches the maximum operating voltage of the DC circuit being protected.

Back to DC Section
Voltage selection is critical: MAXDC models are voltage-specific. Select a model whose voltage rating is appropriate for the DC electrical circuit being protected. Do not substitute a lower-voltage MAXDC model on a higher-voltage system.
15V–100V DC Low-Voltage DC Systems

MAXDC models are available for 15V, 25V, 50V, 60V, 64V, and 100V DC electrical systems.

150V–350V DC Medium-Voltage DC Systems

Choose from 150V, 200V, 250V, 300V, and 350V MAXDC models for compatible DC applications.

380V–600V DC Higher-Voltage DC Systems

MAXDC models are available from 380V through 600V for compatible commercial, solar, wind, and equipment applications.

MAXDC Series: 500kA surge current capacity · Three-stage surge protection · Hardwired ring-terminal connection · DC electrical systems
Selection note: Choose the MAXDC model based on the electrical characteristics of the actual DC circuit. Verify the system operating voltage and the product's voltage rating before installation.
MC4 DC Surge Protectors

MAXSSPMC4 Solar & DC Surge Protectors

The Bad Wolf MAXSSPMC4 series provides high-capacity surge protection for compatible solar, off-grid, battery, and other DC circuits using MC4-style connectors. Models are available from 15V through 600V DC.

Back to DC Section
Choose the voltage rating carefully: The voltage shown for each MAXSSPMC4 model is the maximum DC voltage rating for that product. The protected circuit must remain within the product's specified voltage limits. For solar/PV systems, consider the maximum voltage the circuit can produce, not just its typical operating voltage.
15V–100V DC Low-Voltage MC4 Applications

Available in 15V, 25V, 40V, 50V, 60V, 64V, and 100V DC versions.

145V–350V DC Medium-Voltage Solar / DC

Available in 145V, 150V, 200V, 250V, 300V, and 350V DC versions.

380V–600V DC Higher-Voltage Solar / DC

Available in 380V, 400V, 420V, 450V, 480V, 500V, 550V, and 600V DC versions.

MAXSSPMC4 Series: 500kA surge current capacity · Three-stage surge protection · 30A continuous current rating · Inline MC4-style connections · Positive and negative DC surge protection
500kA 100V DC

MAXSSPMC4-100V

100V DC MC4 Surge Protector

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500kA 145V DC

MAXSSPMC4-145V

145V DC MC4 Solar Surge Protector

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500kA 150V DC

MAXSSPMC4-150V

150V DC MC4 Solar Surge Protector

View Product
500kA 200V DC

MAXSSPMC4-200V

200V DC MC4 Solar Surge Protector

View Product
500kA 250V DC

MAXSSPMC4-250V

250V DC MC4 Solar Surge Protector

View Product
500kA 300V DC

MAXSSPMC4-300V

300V DC MC4 Solar Surge Protector

View Product
500kA 350V DC

MAXSSPMC4-350V

350V DC MC4 Solar Surge Protector

View Product
500kA 380V DC

MAXSSPMC4-380V

380V DC MC4 Solar Surge Protector

View Product
500kA 400V DC

MAXSSPMC4-400V

400V DC MC4 Solar Surge Protector

View Product
500kA 420V DC

MAXSSPMC4-420V

420V DC MC4 Solar Surge Protector

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500kA 450V DC

MAXSSPMC4-450V

450V DC MC4 Solar Surge Protector

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500kA 480V DC

MAXSSPMC4-480V

480V DC MC4 Solar Surge Protector

View Product
500kA 500V DC

MAXSSPMC4-500V

500V DC MC4 Solar Surge Protector

View Product
500kA 550V DC

MAXSSPMC4-550V

550V DC MC4 Solar Surge Protector

View Product
500kA 600V DC

MAXSSPMC4-600V

600V DC MC4 Solar Surge Protector

View Product
Selection note: Verify both the electrical voltage and connector configuration before selecting a MAXSSPMC4 model. The protected circuit must remain within the product's voltage rating. If the installation does not use MC4-style connectors, select an appropriately rated hardwired DC surge protector instead.
NMEA 2000 / Marine DC

NMEA 2000 Marine Surge Protectors

Designed for compatible 12VDC NMEA 2000 marine networks. Choose between protection for the network power feed only or broader protection for both the NMEA 2000 power circuit and CAN/data lines.

Back to DC Section
12VDC NMEA 2000 networks only: These products are designed for compatible 12VDC NMEA 2000 network applications. Do not use them on 24VDC systems, AC electrical circuits, or other incompatible voltages.
POWER FEED PROTECTION SPN2K-12DA

Installs at the NMEA 2000 network power connection and helps protect the 12VDC power conductors only. This model does not provide CAN/data-line surge protection.

SPN2K-12DA 6kA Power Protection Only
SPN2K-12BA 7kA Power + CAN/Data Protection
BOTH MODELS 5A Continuous Power-Circuit Rating
6kA POWER ONLY

SPN2K-12DA

NMEA 2000 12VDC Power Cable Surge Protector

  • 6kA surge current capacity
  • 5A continuous current rating
  • Protects the NMEA 2000 12VDC power feed
  • Does not provide CAN/data-line surge protection
View Product
NMEA 2000 network note: These products use inline NMEA 2000 connections and are intended to complement a properly powered and terminated NMEA 2000 network. The SPN2K-12DA is used for power-feed protection, while the SPN2K-12BA provides additional protection for the network power and CAN/data conductors.
Need Help Choosing?

Not Sure Which Surge Protector You Need?

If you are not sure which Bad Wolf surge protector matches your electrical system, contact us with the system voltage, AC or DC type, application, installation location, and connection or mounting requirements. We can help you identify the Bad Wolf products that best match your application.

Helpful information to send: System voltage, AC or DC, single-phase or three-phase, wye or delta if applicable, equipment being protected, installation location, and preferred connection or mounting style.
For whole-house surge protection: Let us know whether the SPD will be installed at the service entrance, main breaker panel, or a subpanel, along with your preferred panel-mount, liquid-tight, or conduit installation.
For contractors, dealers, and OEMs: Ask about product selection, volume orders, dealer programs, OEM applications, and specialty surge-protection requirements.