Time-delay: A fuse in which the burnout action depends on the time it takes for the overcurrent heat to build up in the fuse and melt the fuse element.
Fast-acting: A fuse that opens on overload and short-circuits very quickly. Fast-acting fuse is not designed to withstand temporary overload currents associated with some electrical loads.
Comments
robert,
You may want to read this article: Fuse ratings and Choosing the correct fuse
The answer to your question is as follows:
Time-delay: A fuse in which the burnout action depends on the time it takes for the overcurrent heat to build up in the fuse and melt the fuse element.
Fast-acting: A fuse that opens on overload and short-circuits very quickly. Fast-acting fuse is not designed to withstand temporary overload currents associated with some electrical loads.
how do select the fuse types?
In general a time delay fuse protects a motor from overload while allowing greater starting amperage to get the motor up to speed.
If you are protecting life and property. A fast acting fuse is best for this.