Protection
High inrush currents occur when switched mode power supplies are turned on. Such high currents are caused by the extremely low impedance of smoothing capacitors or coils which almost produce short circuits at the moment of switching on. Thermistors acting as inrush current limiters are a low cost solution to this problem whilst input varistors are used to provide surge protection against voltage spikes on the input. Gas surge arresters provide protection for N-PE applications.

Thermistors
Product Type | Series | Technical Data | Datasheet | Features Overview |
---|---|---|---|---|
Leaded NTC | S364 |
|
Download |
|
Leaded NTC | S464 |
|
Download |
|
Leaded NTC | P27 |
|
Download |
|
Varistors
Product Type | Series | Technical Data | Datasheet | Features Overview |
---|---|---|---|---|
Leaded Varistors |
StandarD Series |
|
|
|
Leaded Varistors | AdvanceD Series |
|
|
|
Leaded Varistors |
AdvanceD-MP, S14 Series |
|
|
|
Leaded Varistors |
SuperioR-MP, S20 Series |
|
|
|
Housed Varistors |
ThermoFuse T14K130…420E2 |
|
|
|
Housed Varistors |
ThermoFuse T20K460…1000 |
|
|
|
Housed Varistors |
ThermoFuse T20K130…680E2 |
|
|
Arresters
Product Type | Series | Technical Data | Datasheet | Features Overview |
---|---|---|---|---|
Arresters |
LN30… |
|
|
|
Arresters | H3… |
|
|
|
Arresters |
L1... |
|
High Impulse current (10/350 µs) Temporary overvoltage withstand capability IEC 61643-11 |
|
Arresters |
V1… |
|
|
|
Arresters |
A8… |
|
|
|
Arresters |
M5… |
|
|
|
Arresters |
EF… |
|
|
|
Arresters | A7… |
|
Download |
|
Arresters | EHV… |
|
|
Engineering Services
Ask an expert
Have a question? Our regional technical specialists are on hand to help

Inverters and drives brochure
Avnet Abacus offers a comprehensive portfolio of EPCOS and TDK branded products for state-of-the-art inverter and drive design

Input filtering
EMC input filter requirements include limitation of conducted and radiated emissions, immunity to transients and surges on the power lines, and immunity to levels of external electromagnetic radiation and electrostatic discharge.
Learn MoreRectification
Each AC input phase is rectified by 3 diodes (top diode in the positive direction and the low side diode of the other two phases) so that the peak of the negative half cycle appears positive.
Learn MoreDC-Link
A DC-link capacitor is fitted at this point to provide a low impedance path for high frequency switching currents and to provide energy storage.
Learn MoreConversion
At the conversion stage of a variable frequency drive, the DC voltage is converted into an AC voltage at a given but variable voltage and frequency to drive the motor.
Learn MoreThermal management
In a drive, the heatsink’s role is to cool the semiconductors and DC link capacitors and prevent overheating.
Learn MoreDriver and controller
The Control and Feedback stages analyse signals from the current sensors mounted at the motor output, measure the temperature of sensors and control the driver for the conversion semiconductors.
Learn MoreOutput filtering
The output stage of a drive takes a three-phase AC output with variable frequency and amplitude for fine speed and torque control and filters it to minimise EMI and provide reliable operation of the power converter and load.
Learn More