High Voltage Fuse Technology

Transcription

1 High Voltage Fuse Technology For the protection of equipment operating above 00 volts C Current Limiting Current limiting HV fuse links split into three internationally recognised types: backup (or partial range) fuse links, which will interrupt any current from their rated breaking capacity down to a minimum breaking current specified by the manufacturer; and general purpose fuse links, which will interrupt all currents from rated breaking capacity down to a current that will melt the elements within one hour. third type is the full range fuse. This term applies to fuse links that can interrupt any current below the rated breaking capacity that melts the fuse elements satisfactorily. Current limiting backup fuse links are the closest in construction to LV cartridge types. However, a longer strip element with many more restrictions is necessary to produce the large number of series arcs needed to interrupt a high voltage. Fuse manufacturers achieve this by coiling the element around a ceramic core with a star shaped cross section. In this way, a 1m long element can be fitted into a 2mm long fuse body. If the adjacent coils are too close, there will be a flashover between them and this sets a practical limit on how long an element can be crammed into a particular cartridge, and how many elements can be used in parallel. Cross Section End cap Porcelain barrel Star core Moisture tight seal Star core Silver ceramic point contact Striker coil Granular Quartz Fuse elements Fuse elements Granular Quartz Striker coil Expelled striker Porcelain barrel Like an LV cartridge fuse link, an HV fuse link of this type has a ceramic body. Many HV current limiting fuse links are also fitted with a striker mechanism. This not only provides the user with a visual indication that the fuse link has operated, but can also be used to operate other switchgear. In this way, a fuse on a single phase system can cut off all three phases if a fault occurs. Striker mechanisms are driven by explosive charges or compressed springs. Both are triggered by a thin fuse wire running the length of the fuse, usually through the centre of the star shaped core. The wire is connected in parallel with the elements, so a current flows through it when the elements melt. The current heats up the wire and detonates the explosive charge, or melts the wire andreleases the spring, pushing the striker pin out of the fuse link s end cap. lock washer mechanism makes it impossible to push the pin back into the fuse body. There are several variations on this design for specific applications. For example, the elements in threephase motor protection fuse links are corrugated to withstand the cyclical mechanical stresses induced by the high starting and stopping currents drawn by the motor. 1

2 High Voltage Fuse Technology For the protection of equipment operating above 00 volts C Non Current Limiting Essentially, noncurrent limiting fuse links have short elements and incorporate some means of lengthening the arc after the element melts, extinguishing the arc and preventing reignition. There are two distinct types: expulsion fuse links and liquid fuse links. Expulsion fuses are an effective way of protecting overhead distribution lines and transformers. They are designed for outdoor use only and comprise a tin or copper fuse element in series with a flexible braid in a tube. The tube forms one side of a triangle, with a latched connection at the top and a hinge at the bottom. The braid emerges from one end of the fuse link and is held in tension by a spring. When the element melts, the braid is no longer under tension, the latch is released and the fuse swings downwards under gravity, breaking the circuit. s the fuse swings downwards, the arc is lengthened, extinguished and prevented from restriking. Liquid fuse links are based on early noncurrent limiting fuse links which use liquids to quench the arc. The fuse element is anchored to the top ferrule of a glass tube filled with a quenching liquid usually a hydrocarbon. The rest of the tube is filled with a spring that holds the element or a strain wire in very high voltage fuse links in tension. When the element melts, the spring pulls the two parts of the element apart, extending the arc and quenching it in the liquid. M effect Bussmann high voltage fuse links include Meffect as a design feature to enhance performance. Meffect (named after its discoverer, Prof. Metcalf, in the late 1930s) consists of applying overlay spots of special low melting alloy onto the fuse element strips. Its effect is to ensure that the fuse link runs cooler in service and that the maximum temperature reached during fuse operation is kept down to a modest 0 deg. C (compared with deg C for fuse links which do not employ this feature). Meffect has been in widespread use in both low voltage and high voltage fuse links of British design for many years and is now coming into use in many other countries. Cooler running Meffect fuse links have longer service life since lower surface temperature on the elements ensures against long term embrittlement of the material. The Meffect spots are stable and have been proved by many tests to remain inert for periods of 30 years or more. The low maximum operating temperature of Meffect fuse links ensures safe operation of Backup types in striker tripped switchgear under low fault conditions. Whereas non Meffect types are known to have a risk of body fracture because of their much higher body temperature under such conditions. The low maximum operating temperature also ensures against damage to heat sensitive fuse enclosures such as cast resin fuse pods. In short, Meffect fuse links are safer, give better protection and are longer lasting than alternative designs which do not employ this valuable feature. 2

3 DIN Fuse Links Fuse Links comply with DIN dimensional standard DIN436. F range, high performance full range fuse link. S range, high performance backup fuse link, with striker tripping. range, including high current rating backup fuse link. Comply with IEC and VDE 0670 part 4. Wide variety of ratings, kv to 36 kv. Versions suitable for indoor and outdoor use. Motor circuit fuse link option. Bussmann DIN S Fuse Links The time current characteristics of the S range is optimised to ensure improved discrimination with upstream devices and to give fast clearance of earth faults in the secondary terminal zones. The breaking performance with low over currents is adequate to cater for all normal distribution applications, where low voltage fuse links on the secondary side take care of low overload faults, leaving the high voltage fuse links to clear major faults ahead of LV protection. The fuse links are suitable for use even where there is no secondary LV protection, provided that they are used in fuse switches fitted with instantaneous striker tripping. Bussmann DIN F Fuse Links The F range fuse links have full range clearing capability. Bussmann F types are designed to clear all overloads right down to fuse s rated current in accordance with latest IEC 2821 requirements. They are thus suitable for use as a sole form of protection. F range time current characteristics are especially advantageous for transformer protection applications. Bussmann DIN Fuse Links This earlier, well proven design, has values of minimum breaking current between the S and F range including higher current ratings. 3

4 DIN Fuse Links Table of ratings for S range 36kV to DIN dimensions Selection Tables Part Number Voltage Rating U n kv Current Rating I n Breaking Capacity I 1 k Minimum Breaking Current I 3 Cold resistance and watts loss in free air at rated current m Ω W Minimum Prercing Joule Intergral (I 2 t) 2 s Maximum Total Clearing Length mm Diameter ø mm Weight kg SDLSJ SDLSJ SDLSJ SDLSJ SDLSJ SDLSJ SDLSJ SDLSJ SDLSJ X 1 2.5X 2 5.5X 2 9.7X 2 5.7X 2 8.9X 2 2.0X 2 3.2X 2 8.0X 2 6.5X 2 2.7X 3 8.2X 3 1.1X 4 8.0X 3 1.0X 4 2.2X 4 3.2X 4 7.5X SFLSJ SFLSJ0 SFLSJ5 SFLSJ X 3 9.1X 3 1.5X 4 3.0X 4 6.5X 4 1.1X 5 1.7X 5 3.1X SDLSJ SDLSJ SDLSJ SDLSJ SDLSJ SDLSJ SDLSJ SDLSJ SDLSJ X 1 3.1X 2 9.8X 2 5.7X 2 8.9X 2 1.6X 3 3.2X 3 1.3X 3 2.3X 3 6.5X 2 2.7X 3 8.6X 3 5.1X 3 8.1X 4 1.5X 4 2.7X 4 3.2X 4 5.7X SFLSJ SFLSJ SFLSJ SFLSJ X 3 1.0X 4 X 4 1.4X 4 4.1X 4 8.8X 4 1.5X 5 2.2X SKLSJ5 SXLEJ0 SXLEJ X 4 1.1X 5 1.5X 5 2.3X 5 5.0X 5 6.5X SFMSJ0 SKMSJ X 4 2.4X 4 1.4X 5 2.2X SDLSJ SDLSJ SDLSJ SDLSJ SDLSJ SDLSJ SDLSJ X 1 2.8X 2 2.9X 2 5.7X 2 8.9X 2 5.1X 2 8.0X 2 6.1X 2 4.0X 3 2.0X 3 4.4X 3 6.6X 3 1.1X 4 1.8X SFLSJ SFLSJ SFLSJ X 3 5.1X 3 8.1X 3 X 4 3.8X 4 6.0X SDMSJ SDMSJ SDMSJ SDMSJ SDMSJ SDMSJ SDMSJ X 1 3.1X 2 2.9X 2 5.7X 2 8.9X 2 1.6X 3 3.2X 3 6.0X 2 3.8X 3 1.2X 4 6.7X 3 1.1X 4 2.0X 4 X SFMSJ SFMSJ SFMSJ X 3 1.0X 4 X 4 5.5X 4 1.2X 5 X SDMSJ SDMSJ SDMSJ SDMSJ SDMSJ SDMSJ SDMSJ X 1 3.1X 2 9.8X 2 8.1X 2 1.3X 3 X 3 3.2X 3 1.3X 3 5.5X 3 1.5X 4 1.1X 4 2.0X 4 2.9X 4 4.4X SFMSJ SFMSJ SFMSJ SFMSJ71 SHMEJ SHMEJ0 SKMEJ5 SXMEJ X 3 8.1X 3 3.8X 3 5.0X 3 1.7X 4 2.8X 4 2.4X 4 4.4X 4 6.9X 4 9.0X 4 5.0X 4 6.6X 4 8.4X 4 9.3X 4 8.7X 4 1.7X SDQSJ SDQSJ 36SDQSJ 36SDQSJ 36SDQSJ 36SDQSJ 36SFQSJ 36SFQSJ 36SFQSJ 36SXQEJ X 2 3.1X 2 4.6X 2 8.9X 2 1.2X 3 X 3 4.1X 3 8.3X 3 1.1X 4 1.2X 3 X 3 5.1X 3 8.2X 4 1.5X 4 2.3X 4 3.9X 4 8.1X 4 6.2X Rating at 64% 4

5 Selection Tables DIN Fuse Links Table of ratings for F range kv to DIN dimensions Part Number Voltage Rating U n kv Current Rating I n Breaking Capacity I 1 k Minimum Breaking Current I 3 Cold resistance and watts loss in free air at rated current m Ω W Minimum Prercing Joule Intergral (I 2 t) 2 s Maximum Total Clearing Length mm Diameter ø mm Weight kg FDLSJ FDLSJ FDLSJ FDLSJ FDLSJ FDLSJ X 1 2.2X 2 8.8X 2 1.7X 3 2.8X 3 X 3 X 2 X 3 3.9X 3 7.6X 3 1.3X 4 1.3X FFLSJ FFLSJ FFLSJ FXLSJ FXLSJ X 3 6.8X 3 5.1X 3 2.2X 4 4.2X 4 3.8X 4 5.6X 4 5.4X 4 1.1X 5 2.0X FDMSJ FDMSJ FDMSJ FDMSJ FDMSJ FDMSJ X 1 2.7X 2 8.2X 2 1.6X 3 3.4X 3 3.2X 3 5.4X 2 X 3 2.7X 3 5.1X 3 1.2X 4 1.2X FFMSJ FFMSJ FFMSJ FFMSJ X 3 4.7X 3 7.6X 3 X 3 1.1X 4 1.5X 4 2.5X 4 3.0X Table of ratings for range kv to DIN dimensions Part Number Voltage Rating U n kv Current Rating I n Breaking Capacity I 1 k Minimum Breaking Current I 3 Cold resistance and watts loss in free air at rated current m Ω W Minimum Prercing Joule Intergral (I 2 t) 2 s Maximum Total Clearing Length mm Diameter ø mm Weight kg DOSJ DOSJ DOSJ DOSJ DOSJ DOSJ DOSJ X 1 2.3X 2 5.5X 2 9.8X 2 1.3X 2 2.9X 2 8.0X 2 X 2 9.7X 2 2.4X 3 4.2X 3 1.2X 3 2.7X 3 7.5X DLSJ DLSJ DLSJ DLSJ DLSJ DLSJ DLSJ X 1 1.3X 2 3.0X 2 X 2 1.3X 2 2.9X 2 8.0X 2 X 2 5.4X 2 1.3X 3 2.7X 3 1.2X 3 2.7X 3 7.5X ILSJ X 4 2.0X ILSJ ILSJ ILSJ X 3 2.0X 3 5.0X 3 1.8X 4 2.7X 4 7.0X IMSJ X 4 2.0X FMSJ FMSJ IMSJ X 3 3.2X 3 X 3 2.9X 4 4.5X 4 8.5X Notes a) kv fuse links in / dimensions are offered, since some switchgear in the / series is suitable for use at higher voltages. b) Fuse links listed are normally for indoor use but versions suitable for outdoor use are olso available in the same ratings and dimensions. For outdoor versions of the S range, replace the S with a T when ordering for example TDLSJ c) * ll the fuse link code references listed in the proceeding tables are for striker fitted versions, for nonstriker versions please replace the letter S with the letter N in the code for example SDLNJ. For further information on our parts referencing system, please refer to section of this catalogue. 5

6 DIN Fuse Links Time current characteristics for kv DIN Fuse Links, S range, fuse types SDL, SFL PRE RCING TIME IN SECONDS CURVES RELTE TO MEN PRERCING TIME WITH TOLERNCE + % ON CURRENT RMS SYMMETICL PROSPECTIVE CURRENT IN MPERES 5 6

7 DIN Fuse Links Time current characteristics for kv DIN Fuse Links, S range, fuse types SDL, SFL, SKL and SXL PRE RCING TIME IN SECONDS CURVES RELTE TO MEN PRERCING TIME WITH TOLERNCE + % ON CURRENT 0 0 (SDL) (SDL) 0 5 RMS SYMMETICL PROSPECTIVE CURRENT IN MPERES 5 7

8 DIN Fuse Links Time current characteristics for, kv DIN Fuse Links, S range, fuse types SDL, SFL, SDM, SFM and SKM PRE RCING TIME IN SECONDS CURVES RELTE TO MEN PRERCING TIME WITH TOLERNCE + % ON CURRENT (SDM) (SDM) (SFM) /75 0 (kv ONLY) 5 (kv ONLY) RMS SYMMETICL PROSPECTIVE CURRENT IN MPERES 5 8

9 DIN Fuse Links Time current characteristics for kv DIN Fuse Links, S range, fuse types SDM, SXM and SFM PRE RCING TIME IN SECONDS CURVES RELTE TO MEN PRERCING TIME WITH TOLERNCE + % ON CURRENT (SDM) 71 RMS SYMMETICL PROSPECTIVE CURRENT IN MPERES 5 9

10 DIN Fuse Links Time current characteristics for 36kV DIN Fuse Links, S range, fuse types SDQ, SFQ and SXQ PRE RCING TIME IN SECONDS CURVES RELTE TO MEN PRERCING TIME WITH TOLERNCE + % ON CURRENT (SXQ) RMS SYMMETICL PROSPECTIVE CURRENT IN MPERES 5

11 DIN Fuse Links Time current characteristics for kv DIN Fuse Links, F range, fuse types FDL, FFL and FXL PRE RCING TIME IN SECONDS 1 HOUR CURVES RELTE TO MEN PRERCING TIME WITH TOLERNCE + % ON CURRENT 0 RMS SYMMETICL PROSPECTIVE CURRENT IN MPERES 5 11

12 DIN Fuse Links Time current characteristics for kv DIN Fuse Links, F range, fuse types FDM and FFM PRE RCING TIME IN SECONDS 1 HOUR 4 3 CURVES RELTE TO MEN PRERCING TIME WITH TOLERNCE + % ON CURRENT RMS SYMMETICL PROSPECTIVE CURRENT IN MPERES 5

13 DIN Fuse Links Dimensions (mm) Striker characteristics PRODUCT CODE D 26mm maximum travel after operation Please refer to the how to order page 61 of this catalogue for further details of how ordering codes are formatted E = Spring Striker N to IEC designation medium DOSJ SDOSJ DLSJ FDLSJ SDLSJ FDMSJ SDMSJ SDQSJ SFOSJ ILSJ FFLSJ SFLSJ SKLSJ IMSJ FFMSJ SFMSJ SKMSJ SFQSJ SXLSJ SXMSJ SXQSJ FXLSJ S = Spring Striker N to DIN 436 and IEC designation medium Force (N) 30 Force (N) Travel (mm) Travel (mm) 13

14 DIN Fuse Links General guide to the selection of DIN Fuse Links for use in the primary circuit of three phase transformers For HV DIN Fuse Links type SXLSJ, SDLSJ, SFLSJ, SKLSJ, SDMSJ, SFMSJ, SXMSJ SDQSJ, SFQSJ. Selection guide using LV Fuse Links operating class gg/gl on low voltage side for individual cable exit protection. Selection Table for Backup Fuse Links Tranformer Rating (kv) (kv) Rated Current of the High Voltage Fuse Link Min Max Min Max Min Max Transformer Primary Voltage (kv) Rated Current of the High Voltage Fuse Link (kv) Rated Current of the High Voltage Fuse Link For HV DIN Fuse Links type SXLSJ, SDLSJ, SFLSJ, SKLSJ, SDMSJ, SFMSJ, SXMSJ SDQSJ, SFQSJ. Selection guide using LV Fuse Links operating class gg/gl on the low voltage side for overload protection of the transformer. Selection Table for Backup Fuse Links Tranformer Rating (kv) (kv) Rated Current of the High Voltage Fuse Link Transformer Primary Voltage (kv) Rated Current of the High Voltage Fuse Link Min Max Min Max Min Max (kv) Rated Current of the High Voltage Fuse Link Low Voltage NH Fuse Size gg/gl () Selection of these HV fuse links has been based on the following: 1. The fuse link should withstand transformer magnetising inrush currents, taken as times full load current for 0.1 seconds. 2. The fuse link should discriminate with the rating of secondary fuse link stated or where only individual cable exit protection exists, the highest rating likely to be used. 3. The fuse link should operate within 2 seconds for transformers complying with IEC600 5 in respect of impedance, voltage and short circuit withstand current. 4. The fuse link should operate reasonably quickly in the event of a transformer internal fault, or an earth fault in the secondary terminal zone of the transformer. 5. In the case where there is no secondary fuse link for overload protection, the minimum recommended HV fuse link rating applies to the use of fuse links in encapsulated enclosures where permissible continuous overload is generally limited to % of transformer full load current. However if greater overload currents are permissible a higher rating of fuse link may be required. Where the fuse link is used in open air or conditions of unrestricted ventilation a higher permissible overload may be possible. 6. In most cases more than one rating of HV fuse link is recommended for a particular transformer size. Choice of fuse link will then depend on which fuse offers the best protection e.g. having one fuse for several transformer sizes. Recommendations for other voltages are available on request. 14

15 DIN Fuse Links General guide to the selection of DIN Fuse Links for use in the primary circuit of three phase transformers For HV DIN fuse links type SXLSJ, SDLSJ, SFLSJ, SKLSJ, SDMSJ, SFMSJ, SXMSJ SDQSJ, SFQSJ. Selection guide according to DIN VDE 0670 part 2 using LV fuse links operating class gtr on low voltage side for overload protection of the transformer. Selection Table for Backup Fuse Links Tranformer Rating (kv) (kv) Rated Current of the High Voltage Fuse Link Min Max Min Max Min Max Transformer Primary Voltage (kv) Rated Current of the High Voltage Fuse Link 30 (kv) Rated Current of the High Voltage Fuse Link Low Voltage NH Fuse Size gtr () For HV DIN fuse links type FDLSJ, FFLSJ, FXLSJ, FDMSJ, FFMSJ. Selection guide using LV fuse links operating class gg/gl on low voltage side for individual cable exit protection. Selection Table for Full Range Fuse Links Tranformer Rating (kv) (kv) Rated Current of the High Voltage Fuse Link Transformer Primary Voltage (kv) Rated Current of the High Voltage Fuse Link Min Max Min Max Selection of these HV fuse links has been based on the following: 1. The fuse link should withstand transformer magnetising inrush currents, taken as times full load current for 0.1 seconds. 2. The fuse link should discriminate with the rating of secondary fuse link stated or where only individual cable exit protection exists, the highest rating likely to be used. 3. The fuse link should operate within 2 seconds for transformers complying with IEC600 5 in respect of impedance, voltage and short circuit withstand current. 4. The fuse link should operate reasonably quickly in the event of a transformer internal fault, or an earth fault in the secondary terminal zone of the transformer. 5. In the case where there is no secondary fuse link for overload protection, the minimum recommended HV fuse link rating applies to the use of fuse links in encapsulated enclosures where permissible continuous overload is generally limited to % of transformer full load current. However if greater overload currents are permissible a higher rating of fuse link may be required. Where the fuse link is used in open air or conditions of unrestricted ventilation a higher permissible overload may be possible. 6. In most cases more than one rating of HV fuse link is recommended for a particular transformer size. Choice of fuse link will then depend on which fuse offers the best protection e.g. having one fuse for several transformer sizes. Recommendations for other voltages are available on request. 15

16 DIN Fuse Links General guide to the selection of DIN Fuse Links for use in the primary circuit of three phase transformers For HV DIN fuse links type FDLSJ, FFLSJ, FXLSJ, FDMSJ, FFMSJ. Selection guide using LV fuse links operating class gg/gl on low voltage side for overload protection of the transformer. Selection Table for Full Range Fuse Links Tranformer Rating (kv) (kv) Rated Current of the High Voltage Fuse Link Min Max Min Max 0 0 Transformer Primary Voltage 0 0 (kv) Rated Current of the High Voltage Fuse Link Low Voltage NH Fuse Size gg/gl () For fuse links type FDLSJ, FFLSJ, FXLSJ, FDMSJ, FFMSJ. Selection guide according to DIN VDE O670 part 2 using LV fuse links operating class gtr on low voltage side for overload protection of the transformer. Selection Table for Full Range Fuse Links Tranformer Rating (kv) (kv) Rated Current of the High Voltage Fuse Link Transformer Primary Voltage (kv) Rated Current of the High Voltage Fuse Link Min Max Min Max Low Voltage NH Fuse Size gtr (kv) Selection of these HV fuse links has been based on the following: 1. The fuse link should withstand transformer magnetising inrush currents, taken as times full load current for 0.1 seconds. 2. The fuse link should discriminate with the rating of secondary fuse link stated or where only individual cable exit protection exists, the highest rating likely to be used. 3. The fuse link should operate within 2 seconds for transformers complying with IEC600 5 in respect of impedance, voltage and short circuit withstand current. 4. The fuse link should operate reasonably quickly in the event of a transformer internal fault, or an earth fault in the secondary terminal zone of the transformer. 5. In the case where there is no secondary fuse link for overload protection, the minimum recommended HV fuse link rating applies to the use of fuse links in encapsulated enclosures where permissible continuous overload is generally limited to % of transformer full load current. However if greater overload currents are permissible a higher rating of fuse link may be required. Where the fuse link is used in open air or conditions of unrestricted ventilation a higher permissible overload may be possible. 6. In most cases more than one rating of HV fuse link is recommended for a particular transformer size. Choice of fuse link will then depend on which fuse offers the best protection e.g. having one fuse for several transformer sizes. Recommendations for other voltages are available on request.

17 Motor Fuse Links British Standard Motor Fuse Links North merican Motor Fuse Links DIN Dimensioned Motor Fuse Links Motor fuse links comply with IEC602821, IEC644 and BS5907. vailable in DIN 436 and BS2692 dimensions. Sold in a wide range of ratings from: kv 5 to 4 kv 5 to 355 North merican dimensioned products also available. 2R to R ratings. Bussmann Motor Fuse Links The Bussmann range of motor fuse links are designed to meet the specific requirements necessary for motor protection. During the starting cycle of direct online motors, the fuse elements will reach a considerably higher temperature than during normal operation; (this is due to the the high amount of current the motor will draw as it starts, typically, 6 times its normal load current value). This results in expansion and contraction of the fuse elements and could cause premature operation of the fuse. Bussmann motor fuse links encompass an advanced design to minimise this effect. This therefore, negates the need to over specify the fuse rating due to high values of of motor starting current. Bussmann motor fuse links operate extremely quickly under heavy fault currents, resulting from the time / current characteristic. Low power dissipation ensures low temperature rise, important in multitier starters for example. Switching (rc), voltages are lower than permitted values, therefore, 5.5kV fuses are also suitable for 4.8kV and 2.4kV circuits. 17

18 Motor Fuse Links pplication Fuse Links provide short circuit protection in motor circuits to both the motor starter and cables from the starter to the motor. Overload protection is provided by the motor starter, generally by an overload relay and contactor. Combination striker tripping may also form part of associated equipment which houses the fuse links and motor starters. pplication Procedure For any motor the fuse current rating is determined by magnitude and duration of starting current, except in a few situations where the starting currents are very light. The fuse current rating should therefore be selected as follows: Directonline Starting In the absence of specific information the starting current can usually be taken to be six times the motor s full load current. The starting time will depend on the type of the drive but will be approximately as follows: Pump Motors 6 seconds Mill Motors to 15 seconds Fan Motors 60 seconds These are average values and the appropriate figures for starting current and starting time for actual installation should be obtained wherever possible. Multiply the starting current by 1.7 and using this value of current and the starting time, (it is recommended that a minimum time of 5 seconds be adopted), plot this point on the timecurrent characteristics of the fuse link. The correct current rating of the fuse is then chosen as being the one immediately to the right of the point so plotted. The chosen fuse must also have a current rating of at least 1.3 times the fullload current of the associated motor. The rating chosen will be adequate for normal applications where the associated motor is not started more than twice in given period of one hour. For applications using more frequent starting duties, a greater derating factor must be applied as shown in the following table. Maximum 2 starts per hour Derating factor 1.7 Maximum 8 starts per hour Derating factor Maximum 4 starts per hour Derating factor Maximum starts per hour Derating factor 2.4 ssisted Starting similar method of fuse selection may be used as for directonline starting (see above), but it must be noted that the normal running current of the motor is likely to be closer in value to the nominal current rating of the fuse than for directonline applications. The rating of fuse chosen will need to be appreciably greater than the motor running current to allow for restricted cooling inside control gear cubicles, particularly where multitier starters are involved. In case of doubt refer to Bussmann for further guidance. Note For applications involving more frequent starting duties than times per hour or where unusual duty cycles are involved, consult Bussmann application engineers for advice. 18

19 Selection Tables Motor Fuse Links Table of ratings for motor fuses kv to British Standard dimensions Part Number Voltage Rating U n kv Current Rating I n Breaking Capacity I 1 k Minimum Breaking Current I 3 Cold resistance and watts loss in free air at rated current m Ω W Minimum Prercing Joule Intergral (I 2 t) 2 s Maximum Total Clearing Length mm Diameter ø mm Weight kg WJON65 WJON6 WJON6 WJON6 WJON6 WJON6 WJON1.5 WJON6 WJON X 1 1.6X 2 1.6X 2 1.7X 2 3.9X 2 6.1X 2 1.2X 3 X 3 3.2X 3 1.6X 3 1.3X 3 1.3X 3 1.4X 3 3.2X 3 4.9X 3 9.8X 3 1.7X 4 X WDOH6 WDOH6 WDOH6 WDOH60 WDOH X 3 3.8X 3 X 3 9.8X 3 1.5X 4 2.4X 4 4.5X 4 8.0X 4 1.1X 5 2.2X WFOH60 WFOH X 4 5.7X 4 6.2X 5 1.1X 6 WDFHO WDFHO WDFHO WDFHO0 WDFHO X 3 3.1X 3 X 3 9.5X 3 1.3X 4 2.4X 4 4.5X 4 8.0X 4 1.2X 5 1.8X WFFHO0 WFFHO X 4 5.1X 4 4.1X 5 X WKFHO2 WKFHO315 WKFHO355 WKFHO X 5 4.1X 5 6.4X 5 6.4X 5 2.4X 6 5.0X 6 7.0X 6 7.0X WFGHO WFGHO WFGHO WFGHO WFGHO WFGHO0 WFGHO5 WFGHO0 WFGHO0 WFGHO X 2 8.0X 2 1.8X 3 3.2X 3 5.1X 3 7.9X 3 1.2X 4 3.4X 4 5.1X 4 1.3X 5 6.0X 3 1.2X 4 2.2X 4 4.5X 4 7.5X 4 1.2X 5 1.7X 5 4.2X 5 7.0X 5 X WKGHO315 WKGHO355 WKGHO0 WKGHO X 5 6.4X 5 8.2X 5 1.2X 6 6.0X 6 8.5X 6 1.1X 7 1.5X WFNHO WFNHO WFNHO WFNHO WFNHO WFNHO WFNHO0 WFNHO5 WFNHO X 2 3.1X 2 6.1X 2 1.2X 3 X 3 3.8X 3 9.8X 3 2.4X 4 5.0X 4 X 3 4.7X 3 8.0X 3 1.5X 4 3.0X 4 5.8X 4 1.3X 5 2.4X 5 7.0X WKNHO0 WKNHO2 WKNHO2 WKNHO X 4 1.1X 5 2.2X 5 4.5X 5 1.3X 6 1.6X 6 1.6X 6 3.1X WDOH6 fuse links also available in the range to as code DOH6. 19

20 Motor Fuse Links Table of ratings for motor fuses kv to DIN dimensions Selection Tables Part Number Voltage Rating U n kv Current Rating I n Breaking Capacity I 1 k Minimum Breaking Current I 3 Cold resistance and watts loss in free air at rated current m Ω W Minimum Prercing Joule Intergral (I 2 t) 2 s Maximum Total Clearing Length mm Diameter ø mm Weight kg WDOSJ WDOSJ WDOSJ WDOSJ0 WDOSJ X 3 3.8X 3 X 3 9.8X 3 1.5X 4 2.4X 4 4.5X 4 8.0X 4 1.1X 5 2.2X WFOSJ0 WFOSJ X 4 5.7X 4 6.2X 5 1.1X 6 WDLSJ WDLSJ WDLSJ WDLSJ0 WDLSJ5 WFLSJ0 WFLSJ X 3 3.1X 3 X 3 9.5X 3 1.3X 4 3.4X 4 5.1X 4 2.4X 4 4.5X 4 8.0X 4 1.2X 5 1.8X 5 4.1X 5 X WKLSJ2 WKLSJ315 WKLSJ X 5 4.0X 5 6.4X 5 2.4X 6 5.0X 6 7.0X WFMSJ WFMSJ WFMSJ WFMSJ WFMSJ WFMSJ WFMSJ0 WFMSJ5 WFMSJ X 2 3.1X 2 6.1X 2 1.2X 3 X 3 3.8X 3 9.8X 3 2.4X 4 5.0X 4 X 3 4.7X 3 8.0X 3 1.5X 4 3.0X 4 5.8X 4 1.3X 5 2.4X 5 7.0X WKMSJ0 WKMSJ2 WKMSJ2 WKMSJ315 WKMSJ X 4 1.1X 5 2.2X 5 4.5X 5 6.4X 5 1.3X 6 1.6X 6 1.6X 6 3.1X 6 3.9X Higher Current Ratings Higher ratings than those tabulated above can be obtained by using fuse links connected in parallel. Special fixing arrangements for connecting up to 3 fuse links in parallel, are available. Please contact Bussmann application engineers for more details. The code designations for these arrangements are given in How to Order (page 61), dimensional drawings are given on page 26. Table of ratings for motor fuses kV to US dimensions Part Number Voltage Rating U n kv Current Rating I n Breaking Capacity I 1 k Minimum Breaking Current I 3 Cold resistance and watts loss in free air at rated current m Ω W Minimum Prercing Joule Intergral (I 2 t) 2 s Maximum Total Clearing Length mm Diameter ø mm Weight kg 2.75VFRH*R 2.75VFRH*R 2.75VFRH*R 2.75VFRH*R R 3R 4R 6R x 3 x 4 4.2x 4 3.9x 4 2.8x 4 7.5x 4 1.4x 5 3.4x VKRH*R 2.75VKRH*R R R x 4 1.1x 5 8.4x 5 1.2x VKRHK*R 2.75VKRHK*R R R x 5 4.5x 5 3.2x 6 5.5x VFNH*R 5.5VFNH*R 5.5VFNH*R 5.5VFNH*R R 3R 4R 6R x 3 x 4 4.2x 4 3.9x 4 2.8x 4 7.9x 4 1.6x 5 x VKNH*R 5.5VKNH*R R R x 4 1.1x 5 8.8x 5 1.3x VKNHK*R 5.5VKNHK*R R R x 5 4.5x 5 3.4x 6 5.8x

21 Motor Fuse Links Time current characteristics for kv Motor Fuse Links, fuse types DL, WDL, WFL and WKL PRE RCING TIME IN SECONDS CURVES RELTE TO MEN PRERCING TIME WITH TOLERNCE + % ON CURRENT RMS SYMMETICL PROSPECTIVE CURRENT IN MPERES 5 21

22 Motor Fuse Links Time current characteristics for kv Motor Fuse Links, fuse types WDF, WFF and WKF PRE RCING TIME IN SECONDS CURVES RELTE TO MEN PRERCING TIME WITH TOLERNCE + % ON CURRENT RMS SYMMETICL PROSPECTIVE CURRENT IN MPERES 5 22

23 Motor Fuse Links Time current characteristics for kv Motor Fuse Links, fuse types WFG and WKG PRE RCING TIME IN SECONDS CURVES RELTE TO MEN PRERCING TIME WITH TOLERNCE + % ON CURRENT RMS SYMMETICL PROSPECTIVE CURRENT IN MPERES 5 23

24 Motor Fuse Links Time current characteristics for kv Motor Fuse Links, fuse types WFN, WKN, WFM and WKM (* only WKM) PRE RCING TIME IN SECONDS CURVES RELTE TO MEN PRERCING TIME WITH TOLERNCE + % ON CURRENT (WKM)* RMS SYMMETICL PROSPECTIVE CURRENT IN MPERES 5

25 Motor Fuse Links Dimensions (mm) Fuse Link type: DIN FUSE LINK TYPE D WDOSJ WDLSJ WFOSJ WFLSJ WKLSJ WFMSJ WKMSJ 26mm maximum travel after operation Fuse Link type: Tag Type 6 BS 2692 Standard FUSE LINK TYPE +WJON6 WDO*H6 WFO*H B C D 36 E F G 64 H J Fuse type not available with striker Fuse type: WJO min to max mm travel after operation Dimensions in mm Fuse type: WDO, WFO

26 Motor Fuse Links Dimensions (mm) Fuse Link type: Tag Type 0 BS 2692 Standard FUSE LINK TYPE B C D WDFHO WFFHO WKFHO WFGHO WKGHO WFNHO WKNHO min to max mm travel after operation min to max mm travel after operation Triple barrel fuse link (3rd barrel shown dotted) with 03 tags. Double barrel fuse link with 02 tags shown in full lines. 26

27 Dimensions (mm) Motor Fuse Links Fuse Link type: US Motor Tags (ferrule) FUSE LINK TYPE VFRH VKRH VKRHK VFNH VKNH VKNHK Max Min Max striker travel after operation if fitted K Tags (Double barrel fuse links) FUSE LINK TYPE VFRH VKRH VKRHK VFNH VKNH VKNHK Min Max striker travel after operation if fitted K Tags (Double barrel fuse links) 27

28 Dimensions (mm) Motor Fuse Links Fuse Link type: US Motor Tags (ferrule) FUSE LINK TYPE VFRH VKRH VKRHK VFNH VKNH VKNHK Max Min Max striker travel after operation if fitted K Tags (Double barrel fuse links) FUSE LINK TYPE VFRH VKRH VKRHK VFNH VKNH VKNHK Min Max striker travel after operation if fitted K Tags (Double barrel fuse links) 27

29 Voltage and uxiliary Transformer Fuse Links British Standard VT Fuse Links. range of voltage transformer primary Fuse Links to BS26921 and IEC Wide range of ratings from 1 kv to 36 kv mp industry standard current ratings. CV range with ratings from kv to 38kV. Bussmann Voltage and uxiliary Transformer Fuse Links Bussmann manufacture a wide range of voltage transformer (VT) fuse links. In North merica they are referred to as Potential Transformer fuses. These fuse links are designed for use in the primary side of voltage transformers to provide system isolation in the event of faults occurring in the transformer circuit. Voltage transformer fuse links, have a preferred current rating of Experience has shown that there is a risk of spurious operation by transient overcurrents where lower current ratings are used. In addition, in order to minimise the risk of deterioration of the fine fuse elements caused by corona, it is desirable to mount the fuse links so that the earthed metal is not in the immediate vicinity of the part of the barrel between the ferrules. Higher current and E ratings are available for special applications, including auxiliary transformers. range of VT fuse links with a breaking capacity of 0k for use at the output terminals of large turbo alternators can also be ordered. For further information, please contact Bussmann application engineers. Types prefixed or N are suitable for use in ir only. Types prefixed O may be used under oil. For DIN dimensioned voltage transformer and auxiliary transformer fuse links, please refer to DIN dimensioned fuse link section. 28

30 Selection Table Voltage and uxiliary Transformer Fuse Links Table of ratings for voltage transformer fuses kV Part Number Voltage Rating U n kv Current Rating I n Breaking Capacity I 1 k Cold Resistance Ω Minimum Prercing Joule Intergral (I 2 t) 2 s Maximum Total Clearing Length mm Diameter ø mm Weight kg 1.1NBUN*2 1.1NBUN* NBUN* X 0 1.2X 1 3.2X 1 1.8X 1 3.4X 1 9.2X BWN*3.15 BWN* X 0 4.8X 1 1.8X 1 3.1X BCN*3.15 BCN* BCN* X 0 4.8X 1 1.1X 2 1.8X 1 3.1X 2 7.0X MWN0.5E 5.5MWN1E 5.5MWN2E 5.5MWN3E 5.5MWN4E 5.5MWN5E X 0 5.0X 0 4.0X 0 1.8X 1 4.6X 1 7.9X 1 3.5X 0 1.4X 1 1.2X 1 1.1X 2 3.0X 2 5.1X BWN0.5E 5.5BWN1E 5.5BWN2E 5.5BWN3E 5.5BWN5E X 0 2.0X 0 1.2X 0 X 0 3.2X 1 1.4X 0 5.7X 0 3.4X 0 1.8X 1 2.0X BWN*3.15 BWN* X 0 4.8X 1 4.0X 1 3.1X BCN*3.15 BCN* X 0 4.8X 1 4.0X 1 3.1X OBCN*3.15 OBCN* X 0 4.8X 1 4.0X 3.1X OBWN*3.15 OBWN* X 0 4.8X 1 4.0X 3.1X BCN*3.15 OBCN* X 0 X 0 1.8X 1 1.8X BFN*3.15 OBFN* X 0 X 0 4.0X 1 4.0X BGN*3.15 OBGN* X 0 X 0 4.0X 1 4.0X BGN*3.15 OBGN* X 0 X 0 4.0X 1 4.0X OBGN* X 1 7.7X kV GBN* 3.15 is also available for certain indoor applications. Please contact Bussmann s application engineers for further information. * The last letter of the ordering code on these items is normally either or 22, please refer to how to order page 61 for an explanation. Fuse Link type: TG type Ferrule and 22 FUSE LINK TYPE B D NBUN* BWN MWN OBWN* BCN* OBCN* BFN* OBFN* BGN* OBGN* mm bolt with BSW thread Ferrule Fuse Link Tag type shown in full lines and 22 Tag shown in dotted lines 29

31 Voltage and uxiliary Transformer Fuse Links Time current characteristics for to 36kV VT Fuse Links of 3.15, and mp ratings RMS SYMMETICL PROSPECTIVE CURRENT IN MPERES PRE RCING TIME IN SECONDS 3.15* 3 1 HOUR 4 CURVES RELTE TO MEN PRERCING TIME WITH TOLERNCE + % ON CURRENT * Curve valid for all 3.15 ratings shown in the selection table. Curve valid for all ratings shown in the selection table. 5 30

32 Voltage and uxiliary Transformer Fuse Links Time current characteristics for E rated 5.5kV VT Fuse Links, fuse type BWN (minimum melting times) E 1E 8 2E E TIME IN SECONDS E 5E RMS SYMMETRICL CURRENT IN MPS 31

33 Voltage and uxiliary Transformer Fuse Links Time current characteristics for E rated 5.5kV VT Fuse Links, fuse type BWN (maximum melting times) E 1E E 3E TIME IN SECONDS E 5E RMS SYMMETRICL CURRENT IN MPS 32

34 Voltage and uxiliary Transformer Fuse Links Time current characteristics for E rated 5.5kV VT Fuse Links, fuse type MWN (minimum melting times) E 1E E 3E TIME IN SECONDS E RMS SYMMETRICL CURRENT IN MPS 33

35 Voltage and uxiliary Transformer Fuse Links Time current characteristics for E rated 5.5kV VT Fuse Links, fuse type MWN (maximum melting times) E 1E E 3E TIME IN SECONDS E RMS SYMMETRICL CURRENT IN MPS 34

36 Selection Table Voltage and uxiliary Transformer Fuse Links Table of ratings for voltage transformer fuses, 38kV type CV Part Number Voltage Rating U n kv Current Rating I n Breaking Capacity I 1 k Cold resistance in free air at rated current Ω Minimum Prercing Joule Intergral (I 2 t) 2 s Maximum Total Clearing Length mm Diameter ø mm Weight kg CV X 0 1.8X CV15E X 2 3.5X CVH0.5E 5.5CVH1E 5.5CVH2E X 1 1.4X 1 1.8X 1 9.0X 1 9.0X 1 1.1X CV2 CV4 CV6 CV X 0 2.0X 1 4.8X 1 1.1X 2 1.8X 1 5.7X 1 1.4X 2 3.2X CV X 0 1.8X CV0.5E CV1E CV2E CV3E CV5E CV7E X 0 2.0X 0 1.2X 0 4.8X 0 2.0X 1 7.1X 1 1.5X 0 5.8X 0 3.5X 0 1.4X 1 1.3X 2 4.5X CVH0.5E CVH1E CVH2E X 1 1.4X 1 1.8X 1 9.0X 1 9.0X 1 1.1X CV2 CV4 CV6 CV X 0 4.8X 1 1.4X 2 3.2X 2 1.8X 1 1.4X 2 4.0X 2 9.2X CV2 CV3 CV X 0 2.0X 1 4.8X 1 1.8X 1 5.7X 1 1.4X CV2 36CV X 0 4.8X 1 1.8X 1 1.4X CV4E X 1 3.4X CVH0.5E 38CVH1E 38CVH2E X 1 1.4X 1 1.8X 1 9.0X 1 9.0X 1 1.1X These Voltage Transformer fuse links are available in the ratings shown in the table above. CV fuse links are suitable for indoor use in air only. Type CVH Fuse links are fitted with striker pins which may be used for indication purposes. Fuse Link type: CV (Shown with striker fitted) FUSE LINK TYPE CV 5.5CV 5.5CVH CV CV CV CVH CV CV 36CV 38CV 38CVH max mm travel after operation 35

37 Current Limiting Fuse Links for use in Oil Switchgear Fuse Links comply with IEC 2821, BS26921 and ESI Standard 8. and kv Fuse Links tested at highest system voltage and approved by the UK Electricity ssociation approvals panel. Voltage ranges to kv. Fitted with powerful pyrotechnic striker pin. Bussmann under oil Fuse Links The Bussmann range of oil tight fuse links are designed for use in oil filled switchgear. This type was pioneered in the U.K. and the Bussmann range has been in continuous manufacture for almost years, being by far the most widely used device of its kind in the world. Over 1,000,000 Bussmann branded fuse links have been put into service without a single reported case of oil ingress. unique triple seal system ensures against long term seal deterioration. Low power dissipation ensures cool running in oil filled switchgear. The range is not suitable for use inside oil filled transformer tanks where high oil temperatures may be expected. Current Limiting Fuse Links for use in Oil Switchgear Dimensions (mm) 36

38 Current Limiting Fuse Links for use in Oil Switchgear Selection Table Table of ratings for British Standard Oil tight fuses kv Part Number Voltage Rating Current Rating Breaking Capacity Dimensional Reference Cold resistance in free air at rated current Joule Intergral (I 2 t) Length Diameter ø Weight U n kv I n I 1 k BS 2692 m Ω Minimum Prercing 2 s Maximum Total Clearing mm mm kg OEFM OEFM OEFM OEFM OEFM OEFM OEFM OEFM OEFM OEFM OEFM0 OEFM5 OEFM0 OEFM0 OEGM OEGM OEGM0 OEGM5 OEGM0 OEGM0 OLGM2 OEFM OEFM0 OEFM1 OHGM0 OHGM5 OHGM1 OHGM0 OEFM OEFM OEFM OEFM OEFM OEFM OEFM OEFM OEFM OHFM71 OHFM OHGM OHGM OHGM OHGM OHGM OHGM OHGM OHGM OHGM OHGM71 OHGM OHGM90 OHGM0 OLGM5 OEFM OEFM OEFM OEFM OEFM OEFM OEFM OEFM OEFM OHGM71 OHGM OHGM90 OLGM0 OHGM OHGM OHGM 1 7.5OHGM OHGM OHGM OHGM OHGM OHGM OHGM OEGM OEGM OEGM OEGM OEGM OEGM OEGM OEGM F01 F02 F02 F01 F02 F01 F01 F02 F02 F01 F02 F02 F02 F X 1 1.4X 2 1.7X 2 2.7X 2 4.5X 2 1.0X 3 8.9X 3 1.6X 3 3.3X 3 5.2X 3 1.2X 4 X 4 1.5X 4 2.4X 4 3.2X 3 5.2X 3 5.0X 3 X 3 1.3X 4 2.9X 4 5.1X 4 3.2X 3 X 3 9.1X 3 5.0X 3 X 3 9.8X 3 1.3X 4 2.0X 1 1.4X 2 1.7X 2 3.4X 2 4.0X 2 8.9X 2 1.5X 3 2.9X 3 5.1X 3 3.2X 3 4.1X 3 2.0X 1 1.4X 2 1.7X 2 3.4X 2 4.0X 2 8.9X 2 1.5X 3 2.3X 3 4.1X 3 2.0X 3 3.2X 3 3.8X 3 X 3 1.0X 4 4.8X 1 4.0X 1 2.7X 1 4.5X 1 5.2X 1 1.2X 3 1.8X 3 3.3X 3 2.0X 3 2.5X 3 3.2X 3 5.0X 3 X 3 2.0X 1 1.4X 2 1.7X 2 3.4X 2 4.0X 2 9.0X 2 1.5X 3 2.9X 3 5.2X 3 3.8X 3 4.8X 1 2.5X 2 2.7X 2 4.4X 2 5.2X 2 1.2X 3 1.8X 3 1.2X 3 4.9X 2 1.4X 3 2.4X 3 X 3 4.8X 3 8.8X 3 1.0X 4 1.4X 4 2.4X 4 3.4X 4 6.2X 4 9.6X 4 1.6X 5 2.3X 5 X 4 2.7X 4 4.9X 4 6.4X 4 1.0X 5 1.8X 5 2.7X 5 5.8X 4 9.0X 4 1.3X 5 7.5X 4 9.6X 4 1.4X 5 1.8X 5 6.1X 2 1.8X 3 3.0X 3 5.0X 3 6.5X 3 1.2X 4 1.8X 4 2.8X 4 4.3X 4 5.4X 4 7.0X 4 6.1X 2 1.8X 3 3.0X 3 5.0X 3 6.5X 3 1.2X 4 1.8X 4 2.4X 4 3.7X 4 3.9X 4 5.5X 4 6.2X 4 8.9X 4 1.7X 5 1.0X 3 3.4X 3 3.4X 3 4.9X 3 1.1X 4 1.5X 4 2.0X 4 3.0X 4 3.9X 4 4.4X 4 5.4X 4 7.5X 4 9.6X 4 6.1X 2 1.8X 3 3.0X 3 5.0X 3 6.5X 3 1.2X 4 X 4 2.9X 4 4.5X 4 5.7X 4 1.0X 3 3.4X 3 3.4X 3 4.9X 3 1.1X 4 1.5X 4 2.0X 4 2.4X

39 Current Limiting Fuse Links for use in Oil Switchgear General guide to the selection of Oil tight Fuse Links for use in the primary circuit of three phase transformers Transformer Priority Voltage Transformer kv Product Code 3.3kV Current Rating () Rating kv Product Code 6.6kV Current Rating () Rating kv ESI 8 Ref. Product Code 11kV Current Rating () Rating kv Product Code 13.8kV Current Rating () Rating kv / / OEFM OEFM OEFM OEFM OEFM OEFM OLGM OLGM * OEFM OEFM OEFM OEFM OEFM OEFM OHGM OHGM OHGM * OEFM OEFM OEFM OEFM OEFM OEFM OHFM OGFM OGFM OLGM * OEFM OEFM OEFM OEFM OEFM OEFM OEFM OHGM OHGM OLGM * Selection of these fuse links has been based on a compromise between the following: 1 Withstand against magnetising inrush current is taken as times fullload current for 0.1 second. 2 Withstand against 1% permissible overload current. Recommendations marked with an asterisk or dagger have the following significance: * Limited to permissible overload of 130% Permits use of a kv OHFM fuse with a 00 kv transformer where permissible overload does not exceed 130%. 3 For 6.6kV systems, kv fuse links are recommended where possible in the interests of standardisation. 4 Wherever possible, 4mm long fuse links are offered rather than equivalent mm types. 5 The above recommendations are not generally applicable to transformers feeding motor circuits with starting currents in excess of the transformer full load current. In this event, please consult Bussmann application engineers. 38

40 Current Limiting Fuse Links for use in Oil Switchgear Time current characteristics for kv Oil Fuse Links, fuse type OEF PRE RCING TIME IN SECONDS CURVES RELTE TO MEN PRERCING TIME WITH TOLERNCE + % ON CURRENT RMS SYMMETICL PROSPECTIVE CURRENT IN MPERES 39

41 Current Limiting Fuse Links for use in Oil Switchgear Time current characteristics for kv Oil Fuse Links, fuse type OHG PRE RCING TIME IN SECONDS CURVES RELTE TO MEN PRERCING TIME WITH TOLERNCE + % ON CURRENT RMS SYMMETICL PROSPECTIVE CURRENT IN MPERES

42 Current Limiting Fuse Links for use in Oil Switchgear Time current characteristics for kv Oil Fuse Links, fuse types OEF and OHF PRE RCING TIME IN SECONDS CURVES RELTE TO MEN PRERCING TIME WITH TOLERNCE + % ON CURRENT RMS SYMMETICL PROSPECTIVE CURRENT IN MPERES 41

43 Current Limiting Fuse Links for use in Oil Switchgear Time current characteristics for kv Oil Fuse Links, fuse types OHG and OLG PRE RCING TIME IN SECONDS CURVES RELTE TO MEN PRERCING TIME WITH TOLERNCE + % ON CURRENT RMS SYMMETICL PROSPECTIVE CURRENT IN MPERES 42

44 Current Limiting Fuse Links for use in Oil Switchgear Time current characteristics for kv Oil Fuse Links, fuse types OEF, OHG and OLG PRE RCING TIME IN SECONDS CURVES RELTE TO MEN PRERCING TIME WITH TOLERNCE + % ON CURRENT RMS SYMMETICL PROSPECTIVE CURRENT IN MPERES 43

45 Current Limiting Fuse Links for use in Oil Switchgear Time current characteristics for kv Oil Fuse Links, fuse type OHG PRE RCING TIME IN SECONDS CURVES RELTE TO MEN PRERCING TIME WITH TOLERNCE + % ON CURRENT RMS SYMMETICL PROSPECTIVE CURRENT IN MPERES 44

46 Current Limiting Fuse Links for use in Oil Switchgear Time current characteristics for kv Oil Fuse Links, fuse type OEG PRE RCING TIME IN SECONDS CURVES RELTE TO MEN PRERCING TIME WITH TOLERNCE + % ON CURRENT RMS SYMMETICL PROSPECTIVE CURRENT IN MPERES

47 Current Limiting Fuse Links for use in ir High Voltage fuse links for use in ir, comply with BS dimensions. British Standard Range vailable in voltage ranges to 72.5kV. Full range performance option available at kv and kv. Wide variety of fixing arrangements available. Powerful pyrotechnic striker fitted. Erated North merican dimension products also available. Suitable for indoor or outdoor use. Bussmann Fuse Links for use in air The Bussmann range of fuse links for use in air are available in British Standard form, BS 2692, Part number of options are available, including full range capability, and alternative fixing arrangements such as different types of tag, studs and collars etc. Details are available on application. Higher current ratings can be obtained by using fuse links in parallel and special fixing arrangements are available for this purpose. Bussmann ir Range US Dimensions comprehensive range of 'E' rated North merican Dimension fuse links for industrial applications is also available. These are the latest technology full range fuse links in US Industrial Standard 2 inch and 3 inch diameter ferrule style. Extended ratings in double barrel assemblies; striker, indicator and tag versions are also available. 46

48 Current Limiting Fuse links for use in ir Selection Tables Table of ratings for British Standard air fuses 72.5kV Part Number * Voltage Rating U n kv Current Rating I n Breaking Capacity I 1 k Cold resistance in free air at rated current m Ω Minimum Prercing Joule Intergral (I 2 t) 2 s Maximum Total Clearing Length mm Diameter ø mm Weight kg DFH* DFH* DFH* DFH* DFH* DFH* DFH* DGH* DGH* DGH* DGH* DGH* DGH* DGH* DGH* DGH* DGH* DGH*0 DFH* DFH* DFH* DFH* DFH* DFH* DFH* DFH* DFH* FFH* FFH*0 BDGH* BDGH* BDGH* BDGH* BDGH* BDGH* BDGH* BDGH* BDGH* BDGH* BFGH*90 BFGH*0 BFGH*5 BFGH*1 BFGH*0 DFH* DFH* DFH* DFH* DFH* DFH* FFH* FFH* FFH* BDGH* BDGH* BDGH* BDGH* BDGH*22.4 BDGH* BDGH* BDGH* BDGH* BDGH* BDGH* BFGH*56 BFGH* BFGH*71 BFGH* BFGH*90 BFGH*0 KGH*1 KGH* x 1 2.3x 2 x 1 1.1x 2 2.0x 2 3.1x 2 7.1x 2 4.8x 1 3.1x 2 5.5x 2 9.8x 2 1.3x 2 2.9x 2 8.0x 2 1.6x 3 3.1x 3 x 3 9.8x 3 4.8x 1 x 1 x 1 1.1x 2 2.0x 2 3.8x 2 8.0x 2 1.3x 3 2.5x 3 x 3 9.8x 3 5.1x 1 1.0x 2 8.4x 1 1.1x 2 2.0x 2 4.6x 2 8.0x 2 1.6x 3 x 3 6.4x 3 1.0x 4 1.3x 4 1.6x 4 2.4x 4 2.9x 4 4.8x 1 1.3x 2 1.3x 2 3.1x 2 5.1x 2 8.0x 2 1.2x 3 2.0x 3 3.1x 3 5.2x 1 6.4x 1 6.4x 1 1.6x 2 2.4x 2 3.2x 2 5.8x 2 9.0x 2 1.2x 3 1.8x 3 2.5x 3 2.9x 3 3.4x 3 4.6x 3 6.1x 3 8.1x 3 1.1x 3 1.5x 4 x 4 x 2 2.3x 3 1.0x 3 1.5x 3 x 3 2.8x 3 7.7x 3 x 2 4.7x 3 8.3x 3 1.5x 4 1.5x 3 3.5x 3 9.6x 3 x 4 3.7x 4 7.6x 4 1.2x 5 5.6x 2 9.4x 2 8.6x 2 1.5x 3 x 3 4.8x 3 1.1x 4 1.4x 4 2.9x 4 6.9x 4 1.4x 5 6.0x 2 1.3x 3 1.0x 3 1.5x 3 x 3 5.8x 3 1.1x 4 1.8x 4 4.3x 4 7.0x 4 1.4x 5 x 5 x 5 3.3x 5 4.0x 5 5.0x 2 2.0x 3 2.0x 3 3.5x 3 6.1x 3 9.0x 3 1.5x 4 2.5x 4 3.9x 4 5.0x 2 1.0x 3 1.0x 3 1.8x 3 3.0x 3 3.8x 3 6.5x 3 1.1x 4 1.5x 4 2.3x 4 3.2x 4 3.7x 4 4.5x 4 x 4 7.8x 4 1.0x 5 1.4x 5 x 5 2.4x *The last letter of the ordering code on these items describes the tag required, please refer to How to order (page 61) for an explanation. 47

49 Current Limiting Fuse links for use in ir Table of ratings for British Standard air fuses 72.5kV Selection Tables Part Number Voltage Rating U n kv Current Rating I n Breaking Capacity I 1 k Cold resistance in free air at rated current m Ω Minimum Prercing Joule Intergral (I 2 t) 2 s Maximum Total Clearing Length mm Diameter ø mm Weight kg Fullrange FFGN49 FFGN49 FFGN49 FFGN49 FFGN49 FFGN49 FFGN49 FFGN49 BDGH* BDGH* BDGH* BDGH* BDGH* BDGH* BDGH* BFGH* BFGH* BFGH* BFGH*85 DIH DIH DIH DIH DIH DIH FIH FIH FIH FIH FIH90 Fullrange FDIH3.15 FDIH5 FDIH FDIH FDIH FDIH FDIH 36DIH DIH5 36DIH 36DIH 36DIH 36DIH 36DIH 36DIH 36FIH 36FKH 36FKH 36FKH FKH FKH5 72.5FKH 72.5FKH 72.5FKH 72.5FKH 72.5FKH 72.5FKH 72.5FKH x 2 4.2x 2 9.5x 2 1.6x 3 3.1x 3 4.7x 3 8.4x 3 x 3 4.8x 1 x 1 x 1 1.3x 2 2.4x 2 4.9x 2 9.6x 2 1.6x 3 3.2x 3 x 3 x 3 7.9x 1 x 1 1.3x 2 2.0x 2 3.1x 2 4.9x 2 1.2x 3 2.4x 3 3.2x 3 5.5x 3 x 3 3.1x 1 5.9x 1 5.9x 1 2.7x 2 1.1x 3 1.3x 3 5.3x 3 2.0x 1 4.4x 1 7.1x 1 x 1 1.1x 2 2.0x 2 3.1x 2 6.1x 2 1.2x 3 x 3 3.5x 3 5.5x 3 1.4x 1 1.1x 2 x 2 x 1 1.3x 2 3.1x 2 5.1x 2 1.0x 3 2.0x 3 4.7x 3 6.1x 3 1.1x 4 1.5x 4 2.5x 4 3.8x 4 5.6x 4 5.4x 4 8.5x 2 1.2x 3 1.2x 3 2.8x 3 4.3x 3 7.0x 3 1.2x 4 3.2x 4 4.6x 4 1.0x 5 1.0x 5 8.5x 2 1.1x 2 1.7x 3 2.8x 3 4.1x 3 6.8x 3 1.1x 4 2.2x 4 5.2x 4 8.2x 4 1.0x 5 9.8x 1 4.5x 2 4.5x 2 x 3 8.3x 3 4.8x 3 2.0x 4 2.5x 2 5.5x 2 8.9x 2 1.1x 3 1.7x 3 2.8x 3 4.5x 3 8.1x 3 x 4 2.8x 4 5.0x 4 8.2x 4 1.8x 2 1.4x 3 2.5x 3 9.3x 2 1.7x 3 4.0x 3 6.6x 3 1.3x 4 x Notes a) The fifth letter or number of the part reference denotes the end fixing arrangement. b) There are a wide variety of end terminations available, the most popular types, some of which have dimensional references to BS2692: Part 1, are: No Tags Ferrule BS Ref. F3 DIH / BS Ref. F4 FIH / BS Ref. F5 FKH B Offset Tag, single bolt fixing C & D Special Offset Tags, two hole fixings for Brush fuse switch equipment, BS Ref. T3. F & O Offset Tags two bolt fixing. 49 Centre Tags, single bolt fixing for use in Fused End Boxes. 6 Tags to BS26921 ref. T3 48

50 Current Limiting Fuse Links for use in ir General guide to the selection of ir Fuse Links for use in the primary circuit of three phase transformers Transformer Priority Voltage Transformer 6.6kV kv Fuse Type Current Rating Rating kv () Fuse Type 11kV Current Rating () Rating kv Fuse Type 13.8kV Current Rating () Rating kv / /0 00 BDG BDG BDG BFG BFG BFG BFG BFG BFG BFG BDG BDG BDG BDG BDG BFG BFG BFG KG KG BDG BDG BDG BDG BFG BFG BFG BFG BFG Selection of these fuse links has been based on a compromise between the following: 1 The fuse links should withstand transformer magnetising inrush currents, taken as times full load current for 0.1 seconds. 2 The fuse links should discriminate with the highest rating of secondary fuse link. 3 The fuse links should withstand periodic overcurrents of up to 1% of transformer full load current. 4 The fuse links should operate reasonably quickly in the event of a transformer interturn fault or a fault in the secondary terminal zone of the transformer. Notes a) The above recommendations are not generally applicable to transformers feeding motor circuits with starting currents in excess of the rated current of the fuse. In this event, please consult Bussmann. b) For 6.6kV transformers, kv Fuse Links are recommended, where the required current rating is available. c) Where the transformer is not subjected to periodic overcurrents, a lower fuse rating may be suitable, fuse ratings marked thus 3 are only suitable for use with the transformer sizes quoted, where significant over loading does not occur. Fuse links for use in transformers with primary voltages of 3.3kV, 22kV and 33kV are available, please consult Bussmann application engineers for further details and a recommendation. 49

51 Current Limiting Fuse Links for use in ir Time current characteristics for kv ir Fuse Links, fuse types BDG and BFG PRE RCING TIME IN SECONDS CURVES RELTE TO MEN PRERCING TIME WITH TOLERNCE + % ON CURRENT RMS SYMMETICL PROSPECTIVE CURRENT IN MPERES

52 Current Limiting Fuse Links for use in ir Time current characteristics for kv ir Fuse Links, fuse types BDG, BFG and KG PRE RCING TIME IN SECONDS CURVES RELTE TO MEN PRERCING TIME WITH TOLERNCE + % ON CURRENT RMS SYMMETICL PROSPECTIVE CURRENT IN MPERES

53 Current Limiting Fuse Links for use in ir Time current characteristics for kv ir Fuse Links, fuse type FFGN PRE RCING TIME IN SECONDS CURVES RELTE TO MEN PRERCING TIME WITH TOLERNCE + % ON CURRENT RMS SYMMETICL PROSPECTIVE CURRENT IN MPERES 52

54 Current Limiting Fuse Links for use in ir Time current characteristics for kv ir Fuse Links, fuse types DI and FI PRE RCING TIME IN SECONDS CURVES RELTE TO MEN PRERCING TIME WITH TOLERNCE + % ON CURRENT RMS SYMMETICL PROSPECTIVE CURRENT IN MPERES 53

55 Current Limiting Fuse Links for use in ir Time current characteristics for kv ir Fuse Links, fuse type FDI PRE RCING TIME IN SECONDS CURVES RELTE TO MEN PRERCING TIME WITH TOLERNCE + % ON CURRENT RMS SYMMETICL PROSPECTIVE CURRENT IN MPERES 54

56 Current Limiting Fuse Links for use in ir Time current characteristics for 36kV ir Fuse Links, fuse types DI, FI and FK PRE RCING TIME IN SECONDS CURVES RELTE TO MEN PRERCING TIME WITH TOLERNCE + % ON CURRENT RMS SYMMETICL PROSPECTIVE CURRENT IN MPERES 55

57 Current Limiting Fuse links for use in ir Dimensions (mm) C & D Tags CODE B C DØ DFHC DGHC BDGHC FFHD KGHD BFGHD Min Max striker travel after operation if fitted Tags (ferrule) CODE DØ DGH BDGH DIH FDIH KGH BFGH FIH KKH Min Max striker travel after operation if fitted F Tags CODE B C DØ DFHF DGHF BDGHF DIHF FDIHF FFHF KGHF BFGHF FIHF FKHF Min Max striker travel after operation if fitted 56

58 Liquid Fuse Links Replacement liquid fuse links sizes 1, 2 and 3. Wide range of voltages 6.6kV up to 75kV. Current ratings from 2 up to 75 amps (including E rated option). Standard and slow blow elements available. Rewiring kits available for sizes 2 and 3. Size 1 full range cartridge fuse available type FDSH48. Bussmann Liquid Fuse Links Bussmann manufacture a range of liquid filled fuse links for use outdoors, on pole mounted equipment. They provide a simple yet effective means of protection in distribution applications. However, it should be noted that liquid filled fuse links were first put into service before HV fuse standards were introduced and are therefore not covered by any present standard. They are principally for replacement purposes on existing systems. General Description The fuse body is of clear toughened glass to allow visual identification of a blown fuse element. Plated contact ferrules are hermetically sealed onto each end of the tube. The replacement fuse element assembly is held under tension within the tube, which is filled with fuse arc quenching liquid. ( data sheet on this product is available, please contact Bussmann for details.) The upper end of the fuse link is sealed by a tin diaphragm. This is designed to rupture during operation, permitting venting of arc products. The fuse link is sealed against the weather and has an indefinite service life, under normal conditions. The element assembly is enclosed by a fibre sleeve. This assists in the process of arc extinguishing during operation. Operation When a fuse link operates under fault conditions, the element and connecting strain wire melt, the tension spring then pulls the lower contact and element assembly through the arc quenching liquid to the bottom of the fuse link assembly. specially shaped liquid director cone, fitted on the assembly, creates a turbulence in the liquid to ensure rapid dispersal of arc products. Replacement of the Fuse Element Element replacement kits, complete with instructions, are available from Bussmann. We also advise that a minimum of one replacement kit be purchased with each order. Note that Size 1 fuse links do not have replaceable elements. 57

59 Liquid Fuse Links Selection Tables Ordering codes Symbol Rating Voltage Liquid Fuse Designation SIze Characteristic Current Meaning 33 Fuse is rated at 33kV for use on 33kV systems L Denotes a Liquid fuse link 3 Indicates size S Indicates characteristics (F = standard; S = slow blow) Current rating of the fuse link in mps The part number would be 33L3S meaning a fuse with a rated voltage of 33kV; L denoting a Liquid type fuse; 3 denoting size; S denoting slow blow and indicating rated current in mps. Selection Table Dimensions Table of Ratings kv Size B C ØD Size Type Current Rating (mps) Standard Standard Slow Standard Slow 2E 3E 5E 7E E E / 15/

60 Fuse Clips VT Fuse Clips for.4mm diameter. DIN Standard Clips for F and S range fuse links. BS Mounting Clips suitable for.8mm and.2mm Oil, ir and Motor Fuse Links up to 0. Bussmann Fuse Clips To complement the range of tag fixings offered by Bussmann, a range of fuse clips. These are suitable for use with British Standard, DIN dimensioned and VT ferrule style fuse links. The BS and DIN clips are rated up to 0 mps. They are designed to be fitted onto insulated studs or directly onto a busbar. Selection Table Fuse Type Clip Reference DIN fuse links to 43 6 Voltage transformer and auxiliary type fuse links or British standard fuse links.8mm (2 ) dia mm (2.5 ) dia.2mm (3 ) dia