![]() They're often used in transformers & heaters. Thermal fuses are an encapsulated low melting point metal link.There are also a few types of thermal device sometimes used instead of fuses. These include small round encapsulated fuses soldered to a PCB, sometimes surface mount fuses, safety resistors, and less often car type fuses. Other fuse types are also sometimes used in appliances. The slow blow 'nodules' and time delay 'spring' types of fuses are not equivalent, time delays blow a good deal slower than slow blow, and that extra time delay is needed in some applications, such as where relatively high internal switch on currents are involved, as is routinely the case inside appliance power supplies and with motors. T5A - time delay 5A, uses a spring & solder joint.T2A - slow blow 2A, uses fuse wire with a few small nodules on it. ![]() F1A - 1A quick blow fuse, uses a plain fuse wire.The type is indicated by the construction inside the glass and the marking on one metal endcap. Old fuses that use other colours aren't always the rating they should be.ΔΆ0mm & the older 1.25" glass fuses are widely used in appliances. Modern mains plus fuses are ASTA marked and conform to a standard set of colours. A current to the left of both lines will be carried indefinitely, and one to the right of both lines will be disconnected "instantly" (or at lease within the normally required tripping time of 0.4 secs - assuming the current is within the breaking capacity of the fuse). the vertical space between the two lines for the given current and fuse type indicates the range of time required for disconnection to take place. Each fuse has a left and right hand line that represents the lower and upper limits of the expected trip time. To use the graph, look up the prospective fault or overload current along the horizontal axis. The fusing characteristics for 3A and 13A fuses are shown in the graph. Please Note Take care when reading this log/log plot, since it includes an extra division marking the half way point in the first division in each decade - use the printed scale to avoid confusion
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |