14D821K MOV Varistor 820V

14D821K MOV varistor (820V), also known as VDR-14D821K, is designed for AC power lines and high voltage industrial systems where strong surge protection is required.

Unlike lower voltage DC-oriented models, this device is typically used in AC mains circuits and high energy environments where transient overvoltage events such as lightning surges and switching spikes are common.

Typical Use Case:

This model is widely used in AC power supplies, household appliances, industrial equipment, power distribution systems and surge protection devices (SPD) to protect circuits from high energy transient events.

The 14mm disc structure provides reliable energy absorption capability and maintains stable performance under repeated surge conditions.

Key Electrical Characteristics:

Varistor Voltage (1mA): 820V ±10%  

Maximum Continuous Voltage: 510VAC / 670VDC  

Maximum Clamping Voltage: approx. 1355V  

Peak Surge Current (8/20μs): 4.5kA  

Maximum Energy (2ms): 280J  

Capacitance (1kHz): approx. 240pF  

Application Focus:

AC power systems  

Industrial equipment  

Household appliances  

Power distribution systems  

Surge protection devices (SPD)  

Design Tips:

* Select MOV voltage according to AC mains voltage level  

* Install across line-to-line or line-to-ground positions  

* Combine with GDT or TVS for multi-stage protection  

Engineering Insight:

14D821K is typically selected for high voltage AC systems where large surge energy needs to be absorbed. It plays a critical role in protecting circuits against lightning-induced surges and grid instability.

Comparison Insight:

Comparable to TDK EPCOS S14K510, this model can be used as an alternative solution for high voltage AC protection applications.

Related MOV Varistor Models:

14D820K MOV Varistor

14D471K MOV Varistor

14D561K MOV Varistor

Reference Models:  

TDK EPCOS S14K510  

TDK EPCOS B72214S0511K101  

For general AC applications, 14D471K is widely used.  

For higher surge energy requirements, 14D561K is recommended.  

All trademarks and part numbers are used for reference only.

For datasheet, quotation or sample request:  

Email: sales@huaandz.com  

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