Circuit & System Protection


Help for choosing the ideal MOV surge suppressor

25 November 2020 Circuit & System Protection

Almost every designer knows about metal oxide varistors (MOVs). These bidirectional and non-linear surge suppressor devices are ubiquitous in a large variety of applications to limit voltage during a surge or transient event. But how do you choose the best MOV for your design from the multiple form factors and various surge protection ranges?

Bourns has just developed a new white paper entitled ‘Tips on Selecting the Right MOV Surge Suppressor’. In it, the company provides a step-by-step selection approach as well as detailed information on the features and specifications to help you narrow down your search. Below is a quick summary of the key steps:

1. Determine the application’s surge requirement. For instance, a good rule of thumb for selecting an MOV is for the Inom to be typically half of its Imax rating.

2. Determine the operating voltage and the application’s maximum peak voltage.

3. Determine if there are any special requirements such as operating temperature.

4. Consider the highest clamping voltage (Vc) the protected equipment can tolerate.

Other useful information in determining the right MOV is that designers can put MOVs in parallel to decrease the clamping voltage. While this does increase the surge rating, it is not always double the individual MOV rating. That’s because the two MOVs do not share the surge current equally. A good tip is to start with the 60/40 rule, which means that the first MOV that reacts to a surge probably needs to handle 60 percent of the total surge. A good alternative to putting MOVs in parallel is to use an MLV (multi-layer varistor). MLVs are constructed of many layers of MOVs stacked on top of one another and inherently provide matched voltage.

Also, it is beneficial to know that manufacturers can rate their MOVs either AC, DC, and/or Maximum Continuous Operating, and list their clamping voltage at 1 mA DC based on regulatory standards such as IEC 61643-331.

With one of the industry’s most comprehensive lines of MOVs, Bourns has everything from space-saving SMT to high-energy disc and harsh environment AEC-Q200 compliant devices. It also has customised MOV capabilities.

Read the white paper for more tips on finding the right MOV device that meets your application requirements: www.bourns.com/docs/technical-documents/technical-library/varistors/bourns-tips-on-selecting-the-right-mov-surge-suppressor-white-paper.pdf


Credit(s)



Share this article:
Share via emailShare via LinkedInPrint this page

Further reading:

Clearing the Static: Effectively control static in your workplace
Actum Electronics Circuit & System Protection
Controlling electrostatic discharge in the workplace is crucial to protect sensitive electronic equipment from damage. Implementing an ESD control program involves various measures and tests.

Read more...
Low-profile tantalum chip capacitors
Electrocomp Passive Components
These general-purpose tantalum capacitors from Kyocera AVX are available in multiple case sizes with low profile options.

Read more...
Compact high-performance antennas
Electrocomp Telecoms, Datacoms, Wireless, IoT
KYOCERA AVX offers a variety of extremely compact and high-performance internal, on-board, multiprotocol 2,4 GHz antennas ideal for use in SiP applications.

Read more...
Clearing the Static: Staying grounded: Ensuring effective ESD control
Actum Electronics Circuit & System Protection
To maintain reliable electrostatic discharge control, regular testing and accurate measurement are essential, with grounding products and ESD testing equipment being vital.

Read more...
Track with precision
Electrocomp Telecoms, Datacoms, Wireless, IoT
KYOCERA AVX provides innovative antennas for cellular, LTE-M, NB-IoT, LoRa, GNSS, BLE, UWB, Wi-Fi, and future Satellite IoT.

Read more...
RGBIR sensor with I2C interface
Electrocomp Opto-Electronics
Available in a miniature opaque 2,67 x 2,45 mm package, Vishay’s VEML6046X00 includes high-sensitivity photodiodes, a low noise amplifier, and a 16-bit analogue to digital converter.

Read more...
Clearing the Static: ESD component safety in storage and transportation
Actum Electronics Circuit & System Protection
Conductive containers create a Faraday cage effect, safely channelling electrostatic charges away from the components inside.

Read more...
Thick film power resistors
Electrocomp Passive Components
Vishay has released a new product to the market, its thick film power resistor, which is offered in a clip-mount TO-247 package.

Read more...
Clearing the Static: Conductive foot, heel and shoe grounders
Actum Electronics Circuit & System Protection
Conductive foot, heel and shoe grounders are used in electrostatic discharge protected areas to provide a path to ground for static electricity.

Read more...
LED driver for industrial power supply indication
Altron Arrow Editor's Choice Circuit & System Protection
A simple and small solution for driving an LED to provide visual feedback in the presence/absence of a system’s power using a chip not originally designed for this purpose.

Read more...









While every effort has been made to ensure the accuracy of the information contained herein, the publisher and its agents cannot be held responsible for any errors contained, or any loss incurred as a result. Articles published do not necessarily reflect the views of the publishers. The editor reserves the right to alter or cut copy. Articles submitted are deemed to have been cleared for publication. Advertisements and company contact details are published as provided by the advertiser. Technews Publishing (Pty) Ltd cannot be held responsible for the accuracy or veracity of supplied material.




© Technews Publishing (Pty) Ltd | All Rights Reserved