Here’s what more than 2,500 business decision-makers around the world say.Download the report
...with the Facility Hero app in hand! Discover how you can optimize your maintenance efforts today.Learn more
Access tailored services, 24/7 self-service and expert help. Anywhere, anytime, any project.Discover now
Everything you need to know about our IoT technology backbone.Learn more
Explore our global offerings or select your country from one of our five regions.Global
Découvrez nos offres globales ou sélectionnez votre pays dans l’une de nos cinq régions.
When setting the ANSI 50/51N protection, the Sepam relay provides 2 different options for residual current type: "Sum 3I" and "Input Io".
The residual current type depends on the wiring of the current APS_SENSORS to the relay. If, for example, the relay is wired with a standard 3-phase current connection without wiring the Ir input of the CCA634 or using a CSH zero-sequence ct, the "Sum 3I" option needs to be selected. The measurement of the 3-phase currents allows the "calculation" of residual current.
* Note: A 2-phase current connection will not calculate residual current.
If, for example, the CCA634 Ir input is wired or a CSH zero-sequence ct is used, the Sepam will "measure" the residual current and "Input Io" needs to be selected when configuring 50/51N.