FCMOV-T Product Introduction
Current Status of Overvoltage Protection
Metal Oxide Varistors (MOVs) have long been a common solution for overvoltage circuit protection. They are highly cost-effective and an ideal choice for transient surge protection. However, prolonged and repetitive exposure to overvoltage conditions can generate excessive current, which may lead to thermal runaway. Unfortunately, thermal-protection alternatives available in the market are often bulky and expensive.
MOVs can also be affected by continuous abnormal voltages from the power grid, not just short transients. If a varistor is subjected to sustained abnormal overvoltage or overcurrent conditions (such as those required under the UL 1449 safety standard), it may enter a thermal runaway state. This can cause overheating, smoking, or even fire hazards. Beyond the failure of a low-cost component, such incidents may lead to massive compensation claims, lawsuits, and other serious liabilities.
For products to comply with UL 1449 safety standards, MOVs must incorporate a certain level of fail-safe protection.
With the rise of the AI and Industry 4.0 era, the demand for data and analytics highlights the critical importance of safety in telecommunications and interconnected industrial equipment. Overcurrent on data/communication lines, transient voltage surges, and induced overcurrent events may cause service interruptions, system failures, and even potential fire hazards.
Our Solution – FCMOV-T
The FCMOV-T series integrates PPTC and MOV components into a single device. By combining overcurrent and overvoltage protection, it ensures enhanced circuit safety. The PPTC acts as a DC sensing element that limits overcurrent, thereby preventing MOV thermal runaway and helping to maintain the MOV’s surface temperature.
The PPTC prevents damage to the MOV caused by high surge energy, helping to extend the service life of both the MOV and the equipment. Since the PPTC is a resettable component, it automatically recovers once the fault condition is cleared. In the case of transient faults, this greatly reduces the need for maintenance.
PPTC: Activated
Trips to a high-resistance state, limiting the current.
MOV: Inactive
Remains in a high-resistance state.
PPTC: Inactive
Remains in a low-resistance state, allowing current to pass through.
MOV: Activated
Resistance decreases, absorbing transient voltage and energy, and dissipating it as heat.
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PPTC: Inactive → Activated
Switches to a high-resistance state, suppressing the flow of high surge current through the MOV.
MOV: Activated → Partial Operation
Temperature decreases to a non-catastrophic level, preventing the MOV from entering thermal runaway (destructive thermal cycling).
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During prolonged or repetitive transient overvoltage events, this hybrid component allows the MOV’s energy dissipation to be thermally coupled and transferred to the PPTC element, thereby accelerating the PPTC’s tripping speed—up to 10 times faster. In addition, because the PPTC suppresses the large current flowing through the MOV when activated, it further enhances system safety and prevents arcing and combustion (fire hazards).
FCMOV-T Features and Comparison with 2Pro
•Hybrid Design with Patented PPTC Technology
•Standard MOV Packages: Available in 10 mm, 14 mm, and 20 mm disk diameters•High-Level Integrated Protection: Combines overvoltage and overcurrent protection
•Voltage Sharing: When the PPTC trips, voltage is divided with the MOV
•Customizable: Can be tailored to meet specific application requirements
•Faster Response: Provides quicker tripping protection than traditional TMOV devices
•Resettable: Reduces maintenance needs through reusability
•Superior Overcurrent Protection: Extends the lifespan of both MOVs and end products, while further reducing the risk of fire hazards
•Voltage Sharing: When the PPTC trips, voltage is divided with the MOV
•Customizable: Can be tailored to meet specific application requirements
•Faster Response: Provides quicker tripping protection than traditional TMOV devices
•Resettable: Reduces maintenance needs through reusability
•Superior Overcurrent Protection: Extends the lifespan of both MOVs and end products, while further reducing the risk of fire hazards
| FCMOV-T | 2Pro | |
| Protection Mechanism | PTC (Overcurrent Protection & Thermal Protection) | PTC (Overcurrent Protection & Thermal Protection) |
| Safety Standards | ✓ Hybrid Component – UL 1449, Type 4CA ✓ PPTCs: Global Standards – UL 1434, UL 497A (600Vac), IEC-60730, IEC-60738, IEC-62319 ✓ MOVs: Global Standards – UL 1449, Type 5 |
✓ Hybrid Component – N/A ✓ PPTCs: Global Standards – UL 1434, UL 497A ✓ MOVs: Global Standards – UL 1449 |
| Custom Design | Available (customized solutions) | Only standard products provided |
FCMOV-T Operating Principle
Event A:Using a PPTC (0.25A / 600Vac) and a MOV (14D431) as two separate components: the PPTC trips slower than the MOV fails, so the MOV is not protected (Figures 1 and 2).
With the integrated structure, the PPTC trips 10 times faster, preventing the MOV from burning out (Figure 3).
FCMOV-T Operating Principle
Event B: 380Vac / 1ADuring a transient overvoltage event, as shown in Figure 2, when an abnormal condition of 380Vac / 1A occurs, a single MOV (10D271) fails and the current rises from 0.36A to 0.95A (I<sub>Hold</sub> = 0.15A PPTC).
As shown below, in the FCMOV-T series product, the PPTC heats up and trips into a high-resistance state. The current then decreases from 0.28A to 0.01A, thereby reducing the risk of MOV failure as well as potential arcing and combustion (fire hazard).
MOV 14D431K – 500Vdc, 10A Life Test
PPTC + MOV – 500Vdc, 10A Life Test
FCMOV-T (FCMOV14431T075) – 500Vdc, 10A Life Test
FCMOV-T Product Summary
1.High-Voltage Rated PPTC Component
The FCMOV-T series features industry-leading PPTC technology rated up to 600V, meeting the requirements of next-generation telecom and industrial applications.
2.Simple Structure
A straightforward integration of high-voltage PPTC components with MOVs creates a reliable hybrid protection device.
3.Fast Protection Response
With its integrated design, the MOV is safeguarded more quickly and accurately.
4.Improved Coordination
PPTC and MOV elements work together to provide synergistic circuit protection.
5.Comprehensive Safety Certifications
Full safety certifications for PPTC, MOV, and hybrid products help equipment comply with global safety standards.
6.Customizable Solutions
Offers tailored protection solutions, supported by 6 granted patents (with 12 additional patents pending).
The FCMOV-T series features industry-leading PPTC technology rated up to 600V, meeting the requirements of next-generation telecom and industrial applications.
2.Simple Structure
A straightforward integration of high-voltage PPTC components with MOVs creates a reliable hybrid protection device.
3.Fast Protection Response
With its integrated design, the MOV is safeguarded more quickly and accurately.
4.Improved Coordination
PPTC and MOV elements work together to provide synergistic circuit protection.
5.Comprehensive Safety Certifications
Full safety certifications for PPTC, MOV, and hybrid products help equipment comply with global safety standards.
6.Customizable Solutions
Offers tailored protection solutions, supported by 6 granted patents (with 12 additional patents pending).