Protecting the USA’s four wire distribution system

22 April 2020



Electrical switchgear engineering firm NOJA Power reports successful installations and service performance of its Single Triple OSM Recloser in over ten US states.


The modular arrangement of NOJA Power’s single phase reclosers paired with the RC10 or RC15 controller allows independent phase reclosing or optional ganged operation, providing maximum reliability for utilities operating a four- wire distribution system.

Supported locally by the US office in Miami Florida and an extensive network of manufacturer’s representatives, NOJA Power’s Single Triple installations are the latest use- cases for NOJA Power in the United States, following over a decade of supplying three phase distribution automatic circuit reclosers (ACRs) to municipal utility districts and co-ops.

NOJA Power’s policy of equipment integration is a key advantage in distribution applications. By supplying the entire system in a single package, including the ACR, controls, auxiliary supply, communications peripherals and SCADA remote terminal unit (RTU), commissioning and protection design becomes greatly simplified. With a simple installation comes higher reliability and reduced operational costs.

The standard control system supplied with the NOJA Power OSM Recloser is the RC10 or RC15, providing comprehensive protection capabilities to utility engineers. When paired with the Single Triple ACR, this control allows for single phase reclosing and independent protection on each device, whilst simultaneously providing 3 phase protection and lockout features.

Advanced capabilities such as smart grid automation, broken conductor and high impedance fault detection have provided significant reliability improvements to utilities throughout the world, and “these features are now well applied in the Single Triple OSM Recloser in the US”, says NOJA.

“The network in North America is quite unique in the world in that it employs a four wire system and typically unbalanced loads. This offers the advantage of being able to run the network with only one or two phases connected supplying load and a faulted phase isolated,” says NOJA Power Group managing director Neil O’Sullivan. “The development of our single triple product that allows independent fault operation and phase isolation is specific to the four wire application. We have recently developed a single triple product incorporated into a single tank that will reduce the size and cost of installations.”

NOJA Power OSM Recloser systems, in Illinois, USA
NOJA Power OSM Recloser System ANSI protection functions
NOJA Power OSM Recloser systems, in Ohio, USA


Linkedin Linkedin   
Privacy Policy
We have updated our privacy policy. In the latest update it explains what cookies are and how we use them on our site. To learn more about cookies and their benefits, please view our privacy policy. Please be aware that parts of this site will not function correctly if you disable cookies. By continuing to use this site, you consent to our use of cookies in accordance with our privacy policy unless you have disabled them.