IEC & British Fuses IEC & British Standard Fuses IEC and British Standard Fuses Section Contents Application Data Page The standard range of fuses for low voltage industrial and general purpose applications meet the requirements of Application Data ..................... 217-218 BS 88 and IEC 60269. By using advanced fuse technology, CSA Type P and Type D fuses current ratings up to 400A have compact dimensions, but (CDS, CDN & PON) . . . . . . . . . . . . . . . . . . . . . . . . . . . .219 retain standard dimensional and performance requirements. Tron HRC Form II Class C fuses These designs are for 315/240V systems. The standard (CGL Form II Class C) . . . . . . . . . . . . . . . . . . . . . . . . . . 220 range of fuses are available from 2-1250A in the following HRCI Industrial ceramic body fuses (CIF21 HRCI-CA & tag forms: Offset Blade - Offset Bolted - Center Bolted. CIF06 HRCI-CB) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 221 Supplementary ranges cover applications up to 660Vac and HRCI-J Fast-acting fuses (CJ HRCI-J) . . . . . . . . . . . . . . . 222 500Vdc including those with nonstandard tag fixings. HRCI-Miscellaneous Type K fuses (CIH, CIK & Cooper Bussmann fuses are manufactured under quality CIL HRCI-MISC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 223 systems independently assessed to BS 5750 (ISO 9002) and HRC Form II current-limiting fuses . . . . . . . . . . . . . . . . . .224 appropriate ratings carry the ASTA 20 endorsement. BS 88 British Standard low voltage fuses (SSD, NSD, Selecting fuses is relatively simple and effective. The ESD & STD, NITD, AAO, BAO, OSD, CEO, following notes cover the majority of applications. For further DEO BS 88 Part 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . .225 information contact our Application Engineers at BS 88 British Standard low voltage fuses (AC, AD, BC, 636-527-1270. BD, CD, DD, ED, EFS & EF, FF, FG, GF, GG, GH BS 88) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .226 Circuit Loading DIN Style Type D (D16, D27, D33, D125 Type D) . . . . . . 227 The current rating of the fuse should not be less than the full Neozed low voltage fuses (NZ01, NZ02 Type D0) . . . . . . 227 load current of the circuit. The circuit should be so designed NH HRC Fuses . . . . . . . . . . . . . . . . . . . . . . . . . . . . 228-231 that small overloads of long duration will not be of frequent occurrence. Class gG/gL IEC Industrial ferrule fuses (C08G, C08M, C10G, C10M, C14G, C14M, C22G, C22M) . . . . . . . . . . 232 Cable Ratings & Protection Class aM IEC Industrial ferrule fuses (C08M, C10M, There is an increasing move away from 70C PVC insulation C14M, C22M) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .233 to materials that are more environmentally friendly, for Class aM & gG/gL IEC Industrial ferrule fuses with striker example 90C XLPE. The ratings of fusegear, switches, (C14G S, C22G S, C14M S, C22M S) . . . . . . . . . . . . . 234 accessories, etc. are generally based upon the equipment HRC fuse holders being connected to conductors intended to be operated at a CAMaster . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .235 temperature not exceeding 70C in normal service. SAFEloc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .235 In view of the above, it is recommended that the practice of designs based upon conductor temperatures of 70C be regarded as the norm. The equipment manufacturer should be consulted to ascertain the reduction of nominal current RED indicates NEW information rating of the equipment if conductor temperatures exceeding 70C are used. In addition, an overriding factor is often voltage drop. Fuses with gG characteristics protect associated cables against both overload and short-circuit current, provided that the current rating of the fuse 1N is equal or less than the current carrying capacity of the cable 1z. In motor circuits, the motor starter will provide the overload protection and the fuses will provide the short-circuit protection. The maximum fuse size that can be used depends upon the type of cable used and is determined using the appropriate K factor. The following table gives the maximum sizes of fuses that are recommended for two popular cables with copper conductors, 70C PVC (K = 115) and 90C thermosetting (K = 143). For product data sheets, visit www.cooperbussmann.com/datasheets/ulcsa 217IEC & British Standard Fuses Application Data for BS Low Voltage Fuses Max. Fuse Rating (amps) Capacitor Circuits 2 Cable Size (mm ) K = 115 K = 143 11616 For power factor correction in capacitor circuits, the fuse 1,5 20 25* should be chosen with a current rating greater than 1.5 times 2.5 32* 32* the rated capacitor current. This takes into account the high 4 50* 50* inrush current, circuit harmonics and capacitor tolerances. 6 63* 63* 10 100* 125* 16 125* 160* Motor Circuits 25 200* 250* In motor circuits, the fuse has to withstand the motor s 35 315* 355* 50 400* 500 starting current and often requires a higher rating than the 70 560 630 motor s full load current. Coordination recommendations are 95 710 800 made by the manufacturers of motor starters in accordance 120 800 1000 * Extended Motor Circuit dual ratings can be used. with IEC 60947-4-1. To get Type 2 coordination with fuses, tests are performed with the latest gG or gM fuses to BS 88 Protection Against Electrical Shock 2 or IEC 60269 that have pre-arcing I t values towards the For a TN System, a disconnecting time not exceeding 5s is bottom of specified limits. This means that Cooper permitted for a distribution circuit. The maximum values of Bussmann fuses are suitable to provide Type 2 coordination. earth fault loop impedance (Zs) of 240V for Cooper Bussmann gG fuses to BS 88: Parts 2 and 6 are: Extended dual ratings of motor circuit protection fuses with gM characteristics are available in most popular fuse sizes to Rating (A) Zs (Ohms) Rating (A) Zs (Ohms) Rating (A) Zs (Ohms) 6 14 50 1.1 250 0.16 extend the use of associated equipment with appropriate 10 7.7 63 0.86 315 0.13 economies. In the majority of applications, gG fuses are 16 4.3 80 0.60 400 0.096 used. It is not essential to use gM fuses for motor circuit 20 3.0 100 0.44 500 0.073 25 2.4 125 0.35 630 0.054 protection, they simply extend the utilization of standard 32 1.9 160 0.27 800 0.044 equipment. 40 1.4 200 0.20 Below is a table of recommended fuses at 415V. In most Ambient Temperature applications, the run-up time is less than 5 seconds and duty The derating, in terms of current, of 0.5% per C above an is infrequent - no more than twice per hour. The next larger ambient of 35C is recommended. rating should be used for more demanding applications. Interrupting Rating Direct On-line Asst. Start Standard Motor Circuit Standard The standardized interrupting rating values are 80kA for Rating Motor (gG) (gM) (gG) voltages of 415Vac and above, and 40kA for DC kW A A A A applications. The 240Vac designs have an interrupting rating 0.25 0.8 4 - 2 of 50kA. 0.37 1.1 4 - 2 0.55 1.5 6 - 4 Coordination Ratio 0.75 2.0 6 - 4 1.1 3 0 10 - 6 All fuses to BS 88 Parts 2 and 6 will give a coordination ratio 1.5 3.6 16 - 0 1 2.2 5.0 16 - 0 1 of 2:1 and for most practical situations a ratio of 1.6:1 (two 3.0 6.5 20 - 6 1 steps in the R10 series). Example: an upstream fuse rated at 4.0 8.4 20 - 6 1 160A will coordinate with a downstream fuse rated at 100A. 5.5 11.0 25 20M25 2 20 7.5 15.0 40 32M40 25 Current and Energy Limitation 11.0 20.0 50 32M50 32 15.0 27.0 63 32M63 40 2 The range of fuses have pre-arcing I t values towards the 18.5 33.0 80 63M80 50 bottom limits of BS 88 Parts 2 and 6. This ensures excellent 22.0 38.0 80 63M80 50 30.0 54.0 100 63M100 80 current and energy limitation. They also have lower power 37.0 66.0 125 100M125 80 losses at rated current. This assists in the appropriate 45.0 79.0 160 100M160 100 interchangeability with other makes of fuses. 55.0 98.0 160 100M160 100 75.0 135.0 250 200M250 160 Transformers 90.0 155.0 250 200M250 160 110.0 185.0 315 200M315 200 When fuses are used on the primary side of transformers, 132.0 220.0 355 315M400 250 the normal fuse current rating should be at least twice the 150.0 250.0 355 315M400 315 185.0 310.0 450 400M500 355 nominal transformer primary current. 200.0 335.0 500 4 00M500 400 225.0 375.0 560 - 400 Fluorescent Lighting 250.0 415.0 560 - 450 The normal fuse current rating should be at least twice the 280.0 460.0 630 - 500 335.0 562.0 710 - 630 normal full load current of the maximum number of lights to 355.0 596.0 800 - 710 be simultaneously switched. For product data sheets, visit www.cooperbussmann.com/datasheets/ulcsa 218