High Current Fuses MEGA High Performance Fuse Rated 70V-SF51 The MEGA 70V-SF51 High Performance (HP) Fuse is designed for high current circuit protection up to 500A with Diffusion Pill Technology. The MEGA 70V HP features 1MOhm Open State Resistance after fuse opening to guarantee safe interruption at any voltage up to 70V. The MEGA 70V HP Fuse is ideal for battery and alternator protection application and other heavy gauge cables requiring ultra-high current protection. Specifications Voltage Rating: 70 VDC Interrupting Rating: 2500A 70 VDC MEGA 70V HP Fuse-SF51 Recommended Environmental Temperature: -40C to + 125C Terminals Material: Tin Plated Copper Housing Material: PPA-GF33 (U.L. 94 Flammability rating HB) Mounting Torque M6: 9Nm+/-1Nm Mounting Torque M8: 20Nm+/-1Nm Open State Resistance (after fuse opening) >1MOhm Complies With: ISO 20934 - Type SF51 Time-Current Characteristic Curves TIME-CURRENT CHARACTERISTIC CURVES (RECORDED 23 C) Ordering Information Time-Current Characteristics 10000 Opening Time Min / Max (s) Package Bolt Bolt % of Part Number Rating Size Size Hole Qty Rating 60-250A 300A 350-500A 1000 0998xxx.UX-2M8 60 - 500 M8 2 500 75 -/- 14,400 / 14,400 s / 0998xxx.UX-1M8 60 - 500 M8 1 500 100 14,400 / -/- -/- 0998xxx.UX-2M6 60 - 500 M6 2 500 100 135 120 / 1800 120 / 1800 -/- 0998xxx.UX-1M6 60 - 500 M6 1 500 150 20 / 450 20 / 450 -/- 0998xxx.UX-NH 60 - 500 N/A 0 500 200 1 / 15 1 / 15 1 / 15 10 350 0.3 / 5 0.3 / 5 0.5 / 5 600 0.1 / 1 0.1 / 1 0.1 / 1 1 Ratings 2 Current Test Cable Typ. Voltage Typ. Cold Typ. I t 0.1 Part Number Font Color 2 2 Rating (A) Size (mm ) Drop (mV) Resistance (m) (A s) 0998060. 60 6 75.5 0.90 22,800 0.01 0998080. 80 10 88.0 0.75 34,900 10 100 1000 10000 CURRENT A 0998100. 100 10 66.7 0.46 24,000 0998125. 125 16 70.4 0.37 38,000 10000 0998150. 150 25 70.6 0.32 58,100 0998175. 175 25 79.2 0.28 79,300 0998200. 200 35 76.9 0.24 123,600 1000 0998225. 225 35 76.6 0.21 142,500 0998250. 250 50 66.0 0.17 220,000 2 0998300. 300 50 46.9 0.15 340,000 100 1 2 0998350. 350 50 50.7 0.14 495,000 1 2 0998400. 400 70 50.1 0.12 872,000 1 2 0998450. 450 70 52.9 0.10 1,224,000 10 1 2 0998500. 500 70 56.3 0.09 1,800,000 1 Short Circuit Protector only 2 Voltage Drop measurements for short circuit protectors taken at 75% of rated current. 1 2 The typical I t is an average value calculated from the breaking capacity tests by using the melting time before the arcing occurs. 0.1 100 1000 10000 CURRENT A REV07272021 Littelfuse products are not designed for, and shall not be used for, any purpose (including, without limitation, automotive, military, aerospace, medical, life-saving, life-sustaining or nuclear facility applications, devices intended for surgical implant into the body, or any other application in which the failure or lack of desired operation of the product may result in personal injury, death, or property damage) other than those expressly set forth in applicable Littelfuse product documentation. Warranties granted by Littelfuse shall be deemed void for products used for any purpose not expressly set forth in applicable Littelfuse documentation. Littelfuse shall not be liable for any claims or damages arising out of products used in applications not expressly intended by Littelfuse as set forth in applicable Littelfuse documentation. The sale and use of Littelfuse products is subject to Littelfuse Terms and Conditions of Sale, unless otherwise agreed by Littelfuse . littelfuse.com TIME s TIME s 350A 60A 400A 80A 450A 100A 500A 125A 150A 175A 200A 225A 250A 300AHigh Current Fuses MEGA High Performance Fuse Rated 70V-SF51 Dimensions Dimensions in mm for reference only. See outline drawing for dimensions and tolerances. MEGA HP SF51 1 Hole M8/M6 versions MEGA HP SF51 2 Holes M8/M6 versions 68.6 50.8 (25.4) 29.2 M8: 8.6 M8: 8.6 M6: 6.6 M6: 6.6 MEGA HP SF51 No-Holes version Typical Derating Of Fuse Melting Element Temperature Security Margin is 20% Please Contact Littelfuse For Details Regarding Derating Test Set Up WITH CURRENT TAB NAMES 300 6 0A 280 8 0A 100A 260 125A 240 150A Temperature Table 175A 220 200A 200 Max Recommended 225A Environmental 250A max. allowed current load A at ambient temperature 180 300A Temperature 160 -40C 0C 20C 65C 85C 110C 125C 140 120 60A 60 60 60 52 47 39 34 100 80A 80 79 75 63 57 49 43 80 60 100A 100 100 100 84 75 63 55 40 20 125A 125 125 120 101 90 76 66 0 -40 -30 -20 -10 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 150A 150 150 143 119 107 90 78 Ambient Temperature C WITH CURRENT TAB NAMES 175A 175 160 151 126 114 95 83 400 350A 380 200A 200 187 176 148 133 112 98 360 400A 340 225A 225 207 195 163 146 123 106 320 450A 300 500A 280 250A 250 242 229 194 177 151 132 260 Max Recommended 240 Environmental 300A 225 225 225 217 196 166 144 220 Temperature 200 350A 263 263 263 222 200 168 146 180 160 400A 300 300 296 250 226 191 167 140 120 450A 338 338 337 285 257 218 191 100 80 500A 375 344 323 272 246 207 180 60 40 20 0 -40 -30 -20 -10 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 Ambient Temperature C - MIN/MAX CHART AXIS VALUES SHOULD BE ADJUSTED MANUALLY FOR BEST DATA PRESENTATION REV07272021 Littelfuse products are not designed for, and shall not be used for, any purpose (including, without limitation, automotive, military, aerospace, medical, life-saving, life-sustaining or nuclear facility applications, devices intended for surgical implant into the body, or any other application in which the failure or lack of desired operation of the product may result in personal injury, death, or property damage) other than those expressly set forth in applicable Littelfuse product documentation. Warranties granted by Littelfuse shall be deemed void for products used for any purpose not expressly set forth in applicable Littelfuse documentation. Littelfuse shall not be liable for any claims or damages arising out of products used in applications not expressly intended by Littelfuse as set forth in applicable Littelfuse documentation. The sale and use of Littelfuse products is subject to Littelfuse Terms and Conditions of Sale, unless otherwise agreed by Littelfuse . littelfuse.com Derating curves may change depending on the final condition of the application (terminals characteristics, wire size etc..). Please ask Littelfuse for more information. Max. Allowed Current Load A Max. Allowed Current Load A 19.0 16.2 9.9 1.0