Thermal Fusing Three Phase Surge Suppressors
Last Updated: April 1, 2025
Description
Thermal Fusing Three Phase Surge Suppressors are devices designed to protect electrical systems from voltage spikes by interrupting the flow of excessive current. They are specifically engineered to handle three-phase power systems, which are commonly used in industrial and commercial settings.
Working Principle
These surge suppressors operate by utilizing thermal fuses that respond to excessive heat generated by overcurrent conditions. When a surge occurs, the suppressor channels the excess voltage away from the protected equipment, often by short-circuiting the surge to ground. The thermal fuse acts as a safety mechanism, disconnecting the suppressor from the circuit if the temperature rises beyond a safe threshold, thereby preventing damage to the suppressor and the connected equipment. This mechanism is crucial for maintaining the integrity of the electrical system and ensuring continuous operation.
Applications
Thermal Fusing Three Phase Surge Suppressors are used in a variety of applications where three-phase power systems are prevalent. Specific examples include:
- Industrial manufacturing plants where machinery is sensitive to voltage fluctuations.
- Commercial buildings with complex electrical systems that require robust surge protection.
- Data centers where uninterrupted power supply is critical for operations.
Advantages over other Three Phase Surge Suppressors
One of the key advantages of thermal fusing surge suppressors is their ability to provide an additional layer of protection through the thermal fuse mechanism. This feature ensures that the suppressor itself does not become a point of failure during extreme surge events, offering enhanced reliability compared to suppressors without thermal fusing.
Limitations
A notable limitation of thermal fusing surge suppressors is their potential for slower response times compared to other technologies, such as gas arresters, which can affect their performance in rapidly changing surge conditions. Additionally, once the thermal fuse is activated, the suppressor must be replaced or reset, which can lead to downtime.
Considerations
When selecting a thermal fusing three phase surge suppressor, several factors should be considered:
- Initial Costs: These devices may have higher upfront costs due to the inclusion of thermal fuses and other protective features.
- Operating Expense: While generally low, operating expenses can increase if frequent replacements are necessary due to fuse activation.
- Durability: The durability of the suppressor is enhanced by the thermal fuse, but the device's lifespan can be affected by the frequency and severity of surges.
- Replacement and Maintenance Costs: Regular maintenance is required to ensure the suppressor functions correctly, and replacement costs can be significant if the thermal fuse is frequently triggered.
from Schneider Electric Surge Protection
Maintenance free, long life, metal oxide varistor design [See More]
- Features: On-board Thermal Fusing
- Technology: Metal Oxide Varistor
- Mounting: Wall/Panel
- Surge Current: 40000
from Surge Suppression Incorporated
Advantage panel Protection Series, Nema 1, Frequency Responsive Circuitry / Voltage Response Circuitry (Sine Wave Tracking) [See More]
- Features: Integral Audible Alarm (optional feature); Integral Grounding Wire; Hospital Grade (optional feature); Integral Disconnect (optional feature); NEMA Enclosure; NC/NO Dry Contacts (optional feature); Remote alarm contacts (optional feature); Sine-wave Tracking; Surge Counter (optional feature); On-board Thermal Fusing; Simple visual indicators (e.g. LEDs)
- Technology: Hybrid
- Mounting: Device Mount
- Operating Temp: 176
from MCG SURGE PROTECTION
Features: 120LS: I peak=120,000A/Phase (8 x 20 μs waveform). UL1449 3rd Edition. NEMA LS1-1992. Three times redundant protection paths per phase. Employs new 40kA varistors with built in high-speed thermal disconnect. Solid copper bus bar construction. Field-replaceable modules. EMI/RFI noise... [See More]
- Features: Integral Audible Alarm (optional feature); Integral Disconnect (optional feature); NEMA Enclosure; NC/NO Dry Contacts; Remote alarm contacts (optional feature); Performs Self-Diagnostics; Sine-wave Tracking; Surge Counter (optional feature); On-board Thermal Fusing; Simple visual indicators (e.g. LEDs)
- Technology: Metal Oxide Varistor
- Mounting: Wall/Panel; Device Mount
- Surge Current: 120000
from CITEL SURGE PROTECTION
UL Type 1 Surge Protection Device (SPD). Real Time Diagnostics. Optional Intergrated Discount. Itotal 8/20us: 300 kA. Itotal 10/350us: 50 kA. Pluggable module for each mode. UL 1449 4th Edition [See More]
- Features: Integral Audible Alarm; NEMA Enclosure; On/Off Switch; Remote alarm contacts; Performs Self-Diagnostics; Surge Counter; On-board Thermal Fusing; Simple visual indicators (e.g. LEDs)
- Surge Current: 300000
- Mounting: Wall/Panel
- Operating Temp: -58 to 185
from SOCOMEC
The SURGYS G70 surge arrester is designed to ensure reinforced protection of single-phase and three-phase networks. It acts against industrial operation overvoltages and overvoltages owing to lightning. This type of Surge Protective Device is particularly recommended in case of heightened risk of... [See More]
- Features: Remote alarm contacts; On-board Thermal Fusing
- Surge Current: 70000
- Mounting: DIN Rail
- Operating Temp: -40 to 185
from ASCO Power Technologies
Industrial computers, PLCs, and sensitive instrumentation are at the heart of today's automation systems. Maintaining reliability and uptime are essential to the processes running on the factory floor. Semiconductor technology has advanced over the last several decades increasing equipment's... [See More]
- Features: NC/NO Dry Contacts (optional feature); Remote alarm contacts (optional feature); Performs Self-Diagnostics; On-board Thermal Fusing; Simple visual indicators (e.g. LEDs)
- Technology: Metal Oxide Varistor
- Mounting: DIN Rail
- Surge Current: 50000
from Surge Suppression Incorporated
Advantage panel Protection Series, Nema 1, Frequency Responsive Circuitry / Voltage Response Circuitry (Sine Wave Tracking) [See More]
- Features: Integral Audible Alarm (optional feature); Integral Grounding Wire; Hospital Grade (optional feature); Integral Disconnect (optional feature); NEMA Enclosure; NC/NO Dry Contacts (optional feature); Remote alarm contacts (optional feature); Sine-wave Tracking; Surge Counter (optional feature); On-board Thermal Fusing; Simple visual indicators (e.g. LEDs)
- Technology: Hybrid
- Mounting: Device Mount
- Operating Temp: 176
from MCG SURGE PROTECTION
Features: I peak=120,000A/Phase (8 x 20 μs waveform). UL1449 3rd Edition Listed. Triple redundant - three fused surge paths/phase. Remote 1 Form C relay contacts with status LED. Neutral to Ground voltage monitor. Front panel protection status LEDs. Low profile design. All modes protected. [See More]
- Features: NEMA Enclosure; NC/NO Dry Contacts; Remote alarm contacts; Performs Self-Diagnostics; Sine-wave Tracking; Surge Counter (optional feature); On-board Thermal Fusing; Simple visual indicators (e.g. LEDs)
- Technology: Metal Oxide Varistor
- Mounting: Wall/Panel; DIN Rail (optional feature); Device Mount
- Surge Current: 120000
from CITEL SURGE PROTECTION
UL Type 1 Surge Protection Device (SPD). Real Time Diagnostics. Optional Intergrated Discount. Itotal 8/20us: 750 kA. Itotal 10/350us: 50 kA. Pluggable module for each mode. UL 1449 4th Edition [See More]
- Features: Integral Audible Alarm; NEMA Enclosure; On/Off Switch; Remote alarm contacts; Performs Self-Diagnostics; Surge Counter; On-board Thermal Fusing; Simple visual indicators (e.g. LEDs)
- Surge Current: 750000
- Mounting: Wall/Panel
- Operating Temp: -58 to 185
from ASCO Power Technologies
The SPDee Series utilizes large Block 50kA Thermal Protected MOV ’s with surge current levels of 50kA per mode. The unit is a perfect replacement to the obsolete surge arrestors. With a small, compact design and line or load side installation flexibility, this unit can be installed anywhere in... [See More]
- Features: Integral Audible Alarm (optional feature); NEMA Enclosure; NC/NO Dry Contacts (optional feature); Remote alarm contacts (optional feature); Performs Self-Diagnostics; On-board Thermal Fusing; Simple visual indicators (e.g. LEDs)
- Technology: Metal Oxide Varistor
- Mounting: Wall/Panel (optional feature); DIN Rail (optional feature); Pipe Nipple
- Surge Current: 50000
from Surge Suppression Incorporated
Advantage panel Protection Series, Nema 1, Frequency Responsive Circuitry / Voltage Response Circuitry (Sine Wave Tracking) [See More]
- Features: Integral Audible Alarm (optional feature); Integral Grounding Wire; Hospital Grade (optional feature); Integral Disconnect (optional feature); NEMA Enclosure; NC/NO Dry Contacts (optional feature); Remote alarm contacts (optional feature); Sine-wave Tracking; Surge Counter (optional feature); On-board Thermal Fusing; Simple visual indicators (e.g. LEDs)
- Technology: Hybrid
- Mounting: Device Mount
- Operating Temp: 176
from MCG SURGE PROTECTION
Features: I peak=160,000A/Phase (8 x 20 μs waveform). UL1449 3rd Edition Listed. Triple redundant - three fused surge paths/phase. Remote 1 Form C relay contacts with status LED. Neutral to Ground voltage monitor. Front panel protection status LEDs. Low profile design. All modes protected. [See More]
- Features: NEMA Enclosure; NC/NO Dry Contacts; Remote alarm contacts; Performs Self-Diagnostics; Sine-wave Tracking; Surge Counter (optional feature); On-board Thermal Fusing; Simple visual indicators (e.g. LEDs)
- Technology: Metal Oxide Varistor
- Mounting: Wall/Panel; DIN Rail (optional feature); Device Mount
- Surge Current: 160000
from CITEL SURGE PROTECTION
The DS70US is a universal SPD for the most demanding AC Power applications. The DS70US Series protects any single or three phase voltage up to 690Vac from the effects of lightning and switching transients. These SPD are approved to the new UL1449 4th Edition (effective March. 2016) and have... [See More]
- Features: NEMA Enclosure; NC/NO Dry Contacts; On-board Thermal Fusing
- Operating Temp: -40 to 185
- Mounting: DIN Rail
- 3-Phase Configuration: Delta; Wye
from ASCO Power Technologies
Advanced Protection Technologies (APT) has been a worldwide leader in the surge suppression industry since 1985. APT ’s surge protection products have long set the standard for protection of commercial & industrial facilities. surgeassure ™ was formed to bring this same level of... [See More]
- Features: NEMA Enclosure; NC/NO Dry Contacts (optional feature); Remote alarm contacts (optional feature); Performs Self-Diagnostics; Sine-wave Tracking (optional feature); On-board Thermal Fusing; Simple visual indicators (e.g. LEDs)
- Technology: Metal Oxide Varistor; Gas Tubes (optional feature)
- Mounting: Wall/Panel
- Surge Current: 80000 to 150000
from Surge Suppression Incorporated
Individual Circuit Split and Three Phase Protection Series [See More]
- Features: Integral Audible Alarm (optional feature); Continuously Live Electrical Outputs Available; Integral Grounding Wire; Hospital Grade (optional feature); NEMA Enclosure; NC/NO Dry Contacts (optional feature); Remote alarm contacts (optional feature); On-board Thermal Fusing; Simple visual indicators (e.g. LEDs)
- Technology: Hybrid
- Mounting: DIN Rail (optional feature); Device Mount; In-line or Integrally Attached
- Wires: 4-Wire
from MCG SURGE PROTECTION
Features: I peak=250,000A/Phase (8 x 20 μs waveform). UL1449 3rd Edition Listed. Triple redundant - three fused surge paths/phase. Remote 1 Form C relay contacts with status LED. Neutral to Ground voltage monitor. Front panel protection status LEDs. Low profile design. All modes protected. [See More]
- Features: NEMA Enclosure; NC/NO Dry Contacts; Remote alarm contacts; Performs Self-Diagnostics; Sine-wave Tracking; Surge Counter; On-board Thermal Fusing; Simple visual indicators (e.g. LEDs)
- Technology: Metal Oxide Varistor
- Mounting: Wall/Panel; DIN Rail (optional feature); Device Mount
- Surge Current: 250000
from CITEL SURGE PROTECTION
CITEL model DS250VG is a heavy duty AC Surge Protection Device (SPD) for high risk, low tolerance electrical service entrance applications. The DS250VG provides protection against the direct and indirect effects of lightning and is particularly useful in a high lightning area where the risk of heavy... [See More]
- Features: On-board Thermal Fusing
- Technology: VG Technology for Maximum Performance
- Mounting: Symmetrical Rail 35 mm
- Operating Temp: -40 to 185
from ASCO Power Technologies
Our H Series has one, replaceable module per phase and surge current levels of 120kA and 160kA per phase. Our lowest cost replaceable module product for “budget conscience ” projects. FEATURES: UL 1449 Third Edition Listed. 120kA & 160kA per phase ratings. Type 2 SPD – All UL... [See More]
- Features: Integral Audible Alarm; Graphical Display (optional feature); NEMA Enclosure; NC/NO Dry Contacts (optional feature); Remote alarm contacts (optional feature); Performs Self-Diagnostics; Sine-wave Tracking; Surge Counter (optional feature); On-board Thermal Fusing; Simple visual indicators (e.g. LEDs)
- Technology: Metal Oxide Varistor
- Mounting: Wall/Panel
- Surge Current: 120000 to 160000
from Surge Suppression Incorporated
Medium Voltage Panel Protection Series [See More]
- Features: Integral Grounding Wire; Integral Disconnect (optional feature); NEMA Enclosure; On-board Thermal Fusing
- Technology: Hybrid
- Mounting: Device Mount
- Voltage: 2500 Vrms L-L
from MCG SURGE PROTECTION
Features: I peak=40,000A/Phase (8 x 20 μs waveform). UL1449 3rd Edition Listed. Remote 1 Form C relay contacts with status LED. Neutral to Ground voltage monitor. Front panel protection status LEDs. Low profile design. All modes protected. Filtering standard. Thermally protected MOVs. 20 Year... [See More]
- Features: NEMA Enclosure; NC/NO Dry Contacts; Remote alarm contacts; Performs Self-Diagnostics; Sine-wave Tracking; Surge Counter (optional feature); On-board Thermal Fusing; Simple visual indicators (e.g. LEDs)
- Technology: Metal Oxide Varistor
- Mounting: Wall/Panel; DIN Rail (optional feature); Device Mount
- Surge Current: 40000
from CITEL SURGE PROTECTION
CITEL model DS150E is a heavy duty AC Surge Protection Device (SPD) for high exposure applications such as direct lightning strikes, capacitor bank switching and large inductive loads. The DS150E is a single pole device that incorporated a multi-varistor circuit. It offers unmatched mechanical... [See More]
- Features: Integral Disconnect; On-board Thermal Fusing
- Technology: Metal Oxide Varistor
- Mounting: Symmetrical Rail 35 mm
- Operating Temp: -40 to 185
from ASCO Power Technologies
Our H Series has one, replaceable module per phase and surge current levels of 80kA, 120kA and 160kA per phase. Our lowest cost replaceable module product for “budget conscience ” projects. FEATURES: UL 1449 Third Edition Listed. 80 kA, 120kA & 160kA per phase ratings. Type 2 SPD... [See More]
- Features: Integral Audible Alarm; Graphical Display (optional feature); NEMA Enclosure; NC/NO Dry Contacts (optional feature); Remote alarm contacts (optional feature); Performs Self-Diagnostics; Sine-wave Tracking; Surge Counter (optional feature); On-board Thermal Fusing; Simple visual indicators (e.g. LEDs)
- Technology: Metal Oxide Varistor
- Mounting: Wall/Panel
- Surge Current: 80000 to 160000
from MCG SURGE PROTECTION
Features: I peak=80,000A/Phase (8 x 20 μs waveform). UL1449 3rd Edition Listed. Remote 1 Form C relay contacts with status LED. Neutral to Ground voltage monitor. Front panel protection status LEDs. Low profile design. All modes protected. Filtering standard. Thermally protected MOVs. 20 Year... [See More]
- Features: NEMA Enclosure; NC/NO Dry Contacts; Remote alarm contacts; Performs Self-Diagnostics; Sine-wave Tracking; Surge Counter (optional feature); On-board Thermal Fusing; Simple visual indicators (e.g. LEDs)
- Technology: Metal Oxide Varistor
- Mounting: Wall/Panel; DIN Rail (optional feature); Device Mount
- Surge Current: 80000
from CITEL SURGE PROTECTION
CITEL model DS40 is a standard duty AC Surge Protector (SPD) used in distribution or control panel applications. The DS40 is a single pole module that can be combined with other DS40 modules or a DS40G (N-G Mode Only) module. It is configurable for all 1, 2, and 3 phase application up to 480V AC. [See More]
- Features: On-board Thermal Fusing
- Operating Temp: -40 to 185
- Mounting: Symmetrical Rail 35 mm
- 3-Phase Configuration: Delta; Wye
from ASCO Power Technologies
With one, replaceable module per phase and surge current levels of 160kA and 240kA per phase, the XGA Series is a great fit for Service Entrance and Downstream applications. The XGA Features APT ’s Patented TranSafe ™ Circuitry. FEATURES: UL 1449 Third Edition Listed. 160kA & 240kA... [See More]
- Features: Integral Audible Alarm; NC/NO Dry Contacts (optional feature); Remote alarm contacts (optional feature); Performs Self-Diagnostics; Sine-wave Tracking; Surge Counter (optional feature); On-board Thermal Fusing; Simple visual indicators (e.g. LEDs)
- Technology: Metal Oxide Varistor; Silicon Avalanche Diode (optional feature)
- Mounting: Wall/Panel
- Surge Current: 90000 to 240000
from CITEL SURGE PROTECTION
CITEL model DS70RS is a standard duty AC Surge Protector (SPD) used in distribution or control panel applications. The DS70RS is a single pole module. It is configurable for all 1, 2, and 3 phase application up to 70kA. UL1449 3rd Edition. (UL1449 4th Edition - Type 1CA for -400, -600 *Other... [See More]
- Features: On-board Thermal Fusing
- Technology: Metal Oxide Varistor
- Mounting: Symmetrical Rail 35 mm
- Operating Temp: -40 to 185
from ASCO Power Technologies
With surge current levels of 100kA, 150kA, 200kA, 250kA, 300kA, 400kA and 500kA per phase, our XAL Series is the SPD that covers most current SPD needs. With one replaceable module per unit containing Large Block 50kA Thermal Protected MOV ’s, this units low cost, reliability, flexibility and... [See More]
- Features: Integral Audible Alarm; Graphical Display (optional feature); Integral Disconnect (optional feature); NEMA Enclosure; NC/NO Dry Contacts; Remote alarm contacts; Performs Self-Diagnostics; Sine-wave Tracking; Surge Counter (optional feature); On-board Thermal Fusing; Simple visual indicators (e.g. LEDs)
- Technology: Metal Oxide Varistor
- Mounting: Wall/Panel
- Surge Current: 150000
from CITEL SURGE PROTECTION
CITEL model DS240 surge protectors are used mainly for distribution panels of single-phase and three-phase networks. They provide common-mode protection (between the active conductors and ground) and are available with an option remote alarm. The DS240 is built with a plug-in module and a fixed... [See More]
- Features: Integral Disconnect; On-board Thermal Fusing
- Operating Temp: -40 to 185
- Mounting: Symmetrical Rail 35 mm
- 3-Phase Configuration: Delta; Wye
from ASCO Power Technologies
Our largest, highest kA SPD, the XBL Series utilizes two separate, dual redundant replaceable modules that work in parallel. With Large Block 50kA Thermal Protected MOV ’s with surge current levels of 600kA, 800kA and 1000kA per phase, this unit is for those “Mission Critical ”... [See More]
- Features: Integral Audible Alarm; Graphical Display (optional feature); Integral Disconnect (optional feature); NEMA Enclosure; NC/NO Dry Contacts; Remote alarm contacts; Performs Self-Diagnostics; Sine-wave Tracking; Surge Counter (optional feature); On-board Thermal Fusing; Simple visual indicators (e.g. LEDs)
- Technology: Metal Oxide Varistor
- Mounting: Wall/Panel
- Surge Current: 600000
from ASCO Power Technologies
The XCS Series utilizes large Block 50kA Thermal Protected MOV ’s with surge current levels of 100kA per phase. With a compact economical design and line or load side installation flexibility, this unit can be installed anywhere in any electrical distribution system. FEATURES: UL 1449 Third... [See More]
- Features: Integral Audible Alarm (optional feature); NEMA Enclosure; NC/NO Dry Contacts (optional feature); Remote alarm contacts (optional feature); Performs Self-Diagnostics; On-board Thermal Fusing; Simple visual indicators (e.g. LEDs)
- Technology: Metal Oxide Varistor
- Mounting: Wall/Panel
- Surge Current: 100000
from ASCO Power Technologies
The XDS Series utilizes large Block 50kA Thermal Protected MOV ’s with surge current levels of 100kA, 150kA and 200kA per phase. With line or load side installation flexibility, this unit is a great fit from the service entrance all the way down to each distribution and/or branch panel. [See More]
- Features: Integral Audible Alarm (optional feature); NEMA Enclosure; NC/NO Dry Contacts (optional feature); Remote alarm contacts (optional feature); Performs Self-Diagnostics; Sine-wave Tracking; On-board Thermal Fusing; Simple visual indicators (e.g. LEDs)
- Technology: Metal Oxide Varistor
- Mounting: Wall/Panel
- Surge Current: 100000
from ASCO Power Technologies
The XRL Series utilizes uni-modular replaceable module design with Large Block 50kA Thermal Protected MOV ’s with surge current levels of 100kA, 150kA, 200kA, 250kA and 300kA per phase. FEATURES: UL 1449 Third Edition Listed. Directly Connected, Discrete Protection Elements Between All... [See More]
- Features: Integral Audible Alarm; Graphical Display; Integral Disconnect (optional feature); NC/NO Dry Contacts; Remote alarm contacts; Performs Self-Diagnostics; Sine-wave Tracking; Surge Counter (optional feature); On-board Thermal Fusing; Simple visual indicators (e.g. LEDs)
- Technology: Metal Oxide Varistor
- Mounting: Device Mount
- Surge Current: 150000
from ASCO Power Technologies
Our highest kA internal-mount SPD, the XWL Series utilizes uni-modular replaceable module design with Large Block 50kA Thermal Protected MOV ’s with surge current levels of 300kA, 400kA, and 500kA per phase. This unit is for those “Mission Critical ” environments. FEATURES: UL 1449... [See More]
- Features: Integral Audible Alarm; Graphical Display; Integral Disconnect (optional feature); NC/NO Dry Contacts; Remote alarm contacts; Performs Self-Diagnostics; Sine-wave Tracking; Surge Counter (optional feature); On-board Thermal Fusing; Simple visual indicators (e.g. LEDs)
- Technology: Metal Oxide Varistor
- Mounting: Device Mount
- Surge Current: 300000