Fuse Mounting Accessories Page 14 Fuse & Mounting Accessories

2017 Littelfuse, Inc. Specifications are subject to change without notice. Revised: 03/03/17 FUSE Circuit Protection Products and Mounting Accessories UL/CSA/ANCE (Mexico) 248-14 vs. IEC 60127 Part 2 FUSE OPENING TIMES vs. METI/MITI Percent of Rating UL & CSA STD 248-14 IEC TYPE F Sheet 1 (*) IEC TYPE F Sheet 2 (*) IEC TYPE T Sheet 3 (*) IEC TYPE T Sheet 5 (*) METI/MITI 110 4Hr.Min. - - 130 - - - 1Hr.Min. 135 60 Minutes Max. - 150 - 60 Minutes Min. 60 Minutes Min. 60 Minutes Min. 60 Minutes Min. 160 - - - 1Hr.Max. 200 2 Minutes Max. - 2 Minutes Max. 210 - 30 Minutes Max. 30 Minutes Max. 2 Minutes Max. 30 Minutes Max. (*) Note: The IEC Specification is written up to 10.0A. Any components above these ratings are not recognized by the IEC (although the fuses may have similar opening characteristics). IEC also has opening time requirements at 275%, 400% and 1000%; however, the chart is used to show that fuses with the same ampere rating made to different specifications are not interchangeable. According to the IEC 60127 Standard, a one ampere-rated fuse can be operated at one ampere. A one ampere-rated fuse made to UL/CSA/ANCE 248-14 should not be operated at more than .75 ampere (25% derated - See RE-RATING section of FUSEOLOGY). METI B does not differentiate between fast-acting and time delay characteristics. Publication IEC 60127-4 (Universal Modular Fuse-Links [UMF]) This part of IEC 60127-4 covers both PCB through-hole and surface mount fuses. This standard covers fuses rated 32, 63, 125, and 250 volts. This standard will be accepted by UL/CSA making it the first global fuse standard. This specification uses different fusing gates than IEC 60127-2; the gates used here are 125%, 200%, and 1000%. The fuses must not open in less than one hour at 125% of rated current and open within two minutes at 200% of rated current. The 1000% overload is used to determine the fuse characteristic. The opening time for each rating is listed below. Type FF : Less than 0.001 sec. Type F : From 0.001 - 0.01 sec. Type T : From 0.01 - 0.1 sec. Type TT : From 0.1 - 1.00 sec. These characteristics correlate to the terminology used in IEC 60127-1. Breaking capacity (interrupting rating) varies based on voltage rating. Parts rated at 32 & 63 volts must pass a test of 35 amperes or ten times rated current, whichever is greater. Parts rated at 125 volts must pass a test of 50 amperes or ten times rated current, whichever is greater. Parts rated at 250 volts are further defined as either low, intermediate or high breaking. The low breaking capacity fuses must pass a test of 100 amperes rated current, while intermediate breaking capacity fuses must pass a test of 500 amperes and high breaking capacity fuses must pass a test of 1500 amperes. MILITARY/FEDERAL STANDARDS MIL-PRF-15160 and MIL-PRF-23419 These specifications govern the construction and performance of fuses suitable primarily for military electronic applications. MIL-PRF-19207 This specification governs the construction and performance of fuseholders suitable for military applications. DSSC Drawing #87108 This drawing governs the construction and performance of .177" .570" (2AG size) cartridge fuses and axial lead versions suitable for military applications. DSSC #87108 designation is included in the fuse end cap marking. FEDERAL SPECIFICATION W-F-1814 This specification governs the construction and performance of fuses with high interrupting ratings that are approved for federal applications. Fuses approved to these specifications are on the Federal Qualified Products List. Write to the following agencies for additional information on standards, approvals, or copies of the specifications. Underwriters Laboratories Inc. (UL) 333 Pfingsten Road Northbrook, Illinois, USA 60062-2096 Canadian Standards Association (CSA) 5060 Spectrum Way, Suite 100 Mississauga, Ontario, Canada L4W 5N6 International Electrotechnical Commission (IEC) 3, Rue de Varembe 1211 Geneva 20, Switzerland Naval Publications and Military StandardsForm Center (for Military and Federal Standards) 5801 Tabor Avenue Philadelphia, Pennsylvania, USA 19120 Defense Supply Center Columbus (DSCC) 3990 East Broad Street Columbus, Ohio, USA 43218-3990 Ministry of Economy Trade and Industry (METI) 1-3-1 Kasumigaseki Chiyouda-ku, Tokyo 100-8901, Japan Standards (continued)

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