Fusing for Phase Monitor Relays

Posted: 12/15/15 | Three-Phase Monitor Relays


Are fuses required and what size fuse do you recommend using with your Phase Monitor Relays?


The use of fusing in-line with Macromatic phase monitor relays is not required; however, Macromatic recommends using a 2 ampere, fast acting, voltage appropriate fuses such as a KTK fuse between the Phase Monitor Relay and the three phases (see diagram below). Use of fusing in-line with loads controlled by the relay output should also be considered depending on the application. Marked safety and regulatory approvals, including UL Certifications, do not require the use of inline fuses in typical applications. Please be aware that different guidelines may apply in your specific application and/or installation.

Please refer to the appropriate product Instruction Sheet for additional information or contact Macromatic.

Diagram: KTK fuse between Macromatic Phase Monitor and the three phases