FNM-2-1/2

The FNM-2-1/2 is an electrical fuse designed for the protection of certain wiring installations and motor circuits in particular. It has a voltage rating of 500V AC and is rated with a currentInterrupting capacity of 65,000 amperes. In order to ensure that the FNM-2-1/2 performs its protective function effectively, it is designed to open (up to its 65,000A current interrupting capacity) in order to stop the higher than normal current flow in an electric circuit.

The FNM-2-1/2 is designed to open and stop the flow of current if the current level is excessive or rises within the acceptable levels. This is done by sensing the current level in the circuit and if it is above the preset level, then the fuse will open and stop the flow of current.

The FNM-2-1/2 is also designed with a specific response time in order to open quickly when an over-current occurs, thereby preventing damage to the equipment being protected. The response time is typically in the range of 5-10 microseconds.

The FNM-2-1/2 provides protection for applications such as motors, motor feeders, AC circuits and other similar industrial applications that require protection from over-currents. It is also designed to open quickly when short-circuit currents happen and provides protection from power surges. The device is also UL listed for use in hazardous locations.

The FNM-2-1/2 is also constructed with two time-delay spring elements that determine the impedance of the fuse. The fuses will open within the first time-delay on light to medium currents, and then the second time-delay will open the fuse on heavy overloads. This is done to ensure that the fuse does not open at normal in-rush currents or short-time overloading.

The FNM-2-1/2 is available with an optional open-blowing second time-delay element. This is an optional feature that will allow the fuse to open and stop current flow when a short-circuit occurs or the current is above the preset level. This feature is used to ensure that the device can open and stop the current flow in order to prevent damage to the equipment being protected. This is especially important in potentially hazardous conditions.

In conclusion, the FNM-2-1/2 is a specialized electrical fuse designed for the protection of certain wiring installations and motor circuits in particular. It is rated with a current interrupting capacity up to 65,000 amperes and has a voltage rating of 500V AC. The fuse is designed with time-delay springs that determine the impedance of the fuse, allowing it to open on heavy overloads. The FNM-2-1/2 also has an optional open-blowing feature for added protection.