Firmware Update Version 3.10 for SE-330, SE-330AU, SE-330HV

Welcome to the Littelfuse SE-330 Family firmware update page. Please take a moment to fill in this registration form with contact information for the person responsible for maintenance of protection relays and/or electrical equipment at your facility.

Your registration also allows Littelfuse to contact you directly in the future for critical updates, notifications, and feature enhancements to the SE-330 product line and other relevant messages. Littelfuse is excited to release firmware update 3.10 for the SE-330 family. This synchronized update for the SE-330, SE-330AU, and SE-330HV means that sensitive open- and short-circuit detection is now available for neutral-grounding resistors (NGR) up to 72 kV.

With this update, the SE-330AU provides earth-fault protection as well as NER integrity monitoring that is AS/NZS 2081:2011 compliant (Sections 6 and 8 respectively). For Canadian applications, both the SE-330 and SE-330HV can now be used to provide NGR monitoring compliant with CE Code Rule 10-302. For all units, a new special flash pattern on the DIAGNOSTIC LED allows electrical staff and inspectors to confirm that code-compliant sensitive NGR monitoring is configured and activated.

To review hardware compatibility and all changes provided in firmware update v3.10, click the Product Change Notice button below.

For any additional questions, please contact our technical support team at


Product Change Notice