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250FM
Fuse, Semiconductor, FM, 250 A, Fast Acting, 38.1mm x 113mm, 1.5" x 4.45", 500 V
⚠️ Reference pricing provided. In case of supply shortages, we will connect you with our trusted procurement partners to ensure your project's continuity.
- Manufacturer: EATON BUSSMANN
- Product type: Semiconductor Fuses
- Product Range:FM Series; Fuse Current:250A; Blow Characteristic:Fast Acting; Fuse Size Metric:38.1mm x 113mm; Fuse Size Imperial:1.5" x 4.45"; Voltage Rating V DC:500VDC; Voltage Rating VAC:690V
- SVHC: No SVHC (10-Jun-2022)
- Fuse Current: 250A
- Product Range: FM
- Fuse Size Metric: 38.1mm x 113mm
- Fuse Size Imperial: 1.5" x 4.45"
- Voltage Rating VAC: 690V
- Voltage Rating VDC: 500V
- Blow Characteristic: Fast Acting
| Delivery and price | |
|---|---|
| Units per pack | 10 |
| Price | 30.28 € |
| Current stock | 10+ |
| Lead time | 30 days |
Datasheet
**High Speed Fuses** ## **British BS 88 — 690V: 6-710A** ## **CT, ET, FE, EET, FEE, FM, FMM, MT, MMT** ## **Specifications** **Description:** BS 88 style stud-mount fuses. **Dimensions:** See dimensions illustrations. ## **Ratings:** Volts: — 690Vac/500Vdc Amps: — 6-710A IR: — 200kA RMS Sym. **Agency Information:** CE, Designed and tested to: BS 88 Part 4, IEC 269 Part 4, UL Recognized. MT and MMT — 350Vdc (IEC) rating. Consult Cooper Bussmann for UL Recognition status. ## **Electrical Characteristics** **==> picture [249 x 153] intentionally omitted <==** **----- Start of picture text -----**<br> Total Clearing I [2] t<br>1.6<br>The total clearing I [2] t at rated K<br>voltage and at power factor 1.4 eer<br>of 15% are given in the 1.2<br>electrical characteristics. For 1.0<br>other voltages, the clearing 0.8 | | |Lx<br>I [2] t is found by multiplying by<br>0.6 > ane<br>correction factor, K, given asa function of applied working 0.4 EZceam|<br>voltage, Eg, (rms). 0.2 [At 1) 2)<br>E<br>| | | | lt g<br>| [| [| |<br>200 300 400 500 600 690<br>1) CT, ET, EET, FE, FEE, MT, MMT<br>2) FM, FMM<br>**----- End of picture text -----**<br> ## **Arc Voltage** **==> picture [245 x 254] intentionally omitted <==** **----- Start of picture text -----**<br> UL<br>This curve gives the 1500 | | ty<br>1)<br>peak arc voltage, UL,<br>which may appear<br>1000<br>across the fuse during its 2)<br>operation as a function<br>of the applied working 500<br>voltage, Eg, (rms) at a<br>power factor of 15%.<br>E<br>g<br>Power Losses annin 200 400 600 660<br>1) CT<br>Watts loss at rated 2) ET, FE, EET, FEE, FM, FMM<br>current is given in the 1.0<br>electrical characteristics. 0.8 Kp<br>The curve allows the 0.6 SSEEe<br>calculation of the power 0.5<br>losses at load currents 0.4<br>lower than the rated 0.3 seer ann<br>current. The correction<br>0.2<br>factor, Kp, is given as a fle<br>function of the RMS load<br>current, Ib, in % of the 0.1 OEE Ib<br>rated current. 30 40 50 60 70 80 90 100%<br>**----- End of picture text -----**<br> ## **Features and Benefits** - Excellent cycling capability - Excellent DC performance - Low arc voltage and low energy let-through (I[2] t) - Low watts loss ## **Typical Applications** - DC common bus - DC drives - Power converters/rectifiers - Reduced voltage starters **==> picture [508 x 229] intentionally omitted <==** **----- Start of picture text -----**<br> Dimensions (mm)<br>Fig. 1: CT Fig. 2: ET, FE Fig. 3: EET, FEE Fig. 4: FM, MT Fig. 5: FMM, MMT<br>8.7<br>7.1 25.4 25.4<br>4<br>5.5<br>S j<br>en ad — te ‘ Tel<br>48 63.5 77 46 70 94 50 A 113 50 A 113<br>54.8 64.3 74.6<br>14<br>11.9<br>9.7 13.5 10.3<br>im uy 12.7 nfl 31.8 bey! =i<br>10.3<br>6.4 EE 17.1 3 7<br>8.7 8.7 19.1 19 41 83<br>vo 5 aaa > ° F<br>80) CE °° @! 3 8. 1 |<br>38<br>1mm = 0.0394” / 1” = 25.4mm Figs. 4 & 5 “A” Dimensions<br>Type “A”<br>FM 80-85mm<br>FMM 80-85mm<br>MT 85mm<br>MMT 85mm<br>**----- End of picture text -----**<br> **Data Sheet: 720024** For product data sheets, visit www.cooperbussmann.com/datasheets/ulcsa **191** **High Speed Fuses** ## **British BS 88 — 690V: 6-710A** ## **Catalog Numbers** ## **CT 6-20, ET 25-80A: 690V** ||||**Electrical **|**Characteristics**|**Characteristics**||||||||||||||||||||||||||||||||||||||||||||||||||||||| |---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---| |**Catalog**||**Rated**<br>**Current**||**I2t (A2 Sec)**<br>**Clearing**<br>**Clearing**||**Watts**|**Time-Current**||||||||||||||**Curve**||||||||||||||||||||||||||||||||||||||| |**Numbers**|**Type**|**RMS-Amps**|**Pre-arc**|**at 415V**|**at 660V**|**Loss**||104|||||||||||||||||||||||||||||||||||||||||||||||||||| |6CT||6|1.8|8.5|12|2||6|||||||||||||||||||||||||||||||||||||||||||||||||||| |10CT||10|7|30|48|3||4|||||||||||||||||||||||||||||||||||||||||||||||||||| |12CT|CT|12|10|40|65|3||2|||||||||||||||||||||||||||||||||||||||||||||||||||| |16CT<br>20CT||16<br>20|16<br>32|66<br>150|110<br>220|7<br>7||103<br>6|||||||||||||||||||||||||||||||||||||||||||||||||||| |25ET||25|25|150|250|7||4|||||||||||||||||||||||||||||||||||||25ET||||||||||||||| |32ET||32|32|190|350|11||2|||||||||||||||||||||||||||||||||||||32ET||||||||||||||| |35ET<br>40ET<br>45ET|ET|35<br>40<br>45|52<br>103<br>103|310<br>600<br>680|500<br>900<br>1100|11<br>9<br>11||6<br>4<br>102|||||||||||||||||||||||||||||||||||||56ET<br>45ET<br>40ET<br>35ET||||||||||||||| |56ET<br>63ET<br>80ET<br>35FE<br>40FE<br>45FE<br>50FE<br>63FE<br>71FE<br>80FE|FE|56<br>63<br>80<br>35<br>40<br>45<br>50<br>63<br>71<br>80|135<br>171<br>360<br>33<br>52<br>76<br>103<br>135<br>210<br>250|950<br>1200<br>2500<br>130<br>180<br>270<br>380<br>480<br>600<br>900|1500<br>2000<br>4000<br>200<br>300<br>450<br>600<br>750<br>950<br>1500|14<br>16<br>18<br>9<br>9<br>11<br>11<br>12<br>17<br>20|Virtual Pre-Arcing Time In Seconds|2<br>6<br>4<br>100<br>2<br>6<br>4<br>101<br>2|||||||||10CT<br>12CT<br>16CT<br>20CT<br>6CT||||||||||||||||||||||||||||80ET<br>63ET||||||||||||||| |90FE||90|360|1300|2100|20|10–1||||||||||||||||||||||||||||||||||||||||||||||||||||| |100FE<br>90EET||100<br>90|470<br>490|1800<br>3000|2800<br>4500|23<br>19||4<br>6|||||||||||||||||||||||||||||||||||||||||||||||||||| |110EET<br>140EET|EET|110<br>140|600<br>1050|4000<br>7000|6500<br>12000|27<br>35|2<br>10–2||||||||||||||||||||||||||||||||||||||||||||||||||||| |160EET||160|1500|10000|17000|39||6|||||||||||||||||||||||||||||||||||||||||||||||||||| |100FEE<br>120FEE||100<br>120|400<br>540|1600<br>1900|2400<br>3100|24<br>32||4<br>2|||||||||||||||||||||||||||||||||||||||||||||||||||| |140FEE<br>160FEE|FEE|140<br>160|850<br>1000|2500<br>3700|3800<br>5700|36<br>46|6<br>10–3||||||||||||||||||||||||||||||||||||||||||||||||||||| |180FEE<br>200FEE||180<br>200|1400<br>1900|5300<br>7100|8400<br>11400|46<br>52||2<br>4|||||||||||||||||||||||||||||||||||||||||||||||||||| |180FM<br>200FM||180<br>200|1400<br>2600|7500<br>10500|13500<br>18500|40<br>40|10–4||2|||||4||||6|||8||101||||**2**|||||||4||6<br>8||102|||||**2**|||||4||||6||8|||103||| |225FM||225|3700|14500|26500|44||||||||||||||||||||Prospective Current In Amps RMS|||||||||||||||||||||||||||||||||| |250FM|FM|250|5200|20500|37500|48|||||||||||||||||||||||||||||||||||||||||||||||||||||| |280FM||280|7000|30500|55000|48|||||||||||||||||||||||||||||||||||||||||||||||||||||| |315FM||315|10000|40000|77000|55|||||||||||||||||||||||||||||||||||||||||||||||||||||| |350FM<br>400FMM||350<br>400|15000<br>10000|60000<br>40000|105000<br>72500|55<br>85|**Peak**||||**Let-Through**|||||||||||||||**Curve**|||||||||||||||||||||||||||||||||| |450FMM<br>500FMM<br>550FMM|FMM|450<br>500<br>550|15000<br>20000<br>30000|60000<br>82000<br>120000|105000<br>150000<br>215000|90<br>100<br>100||4<br>6||||||||||||||||||||||||||||710MMT<br>630MMT<br>560MMT|||||||||||||||||||||||| |630FMM||630|45000|180000|310000|100||2||||||||||||||||||||||||||||500MMT<br>450MMT|||||||||||||||||||||||| |700FMM<br>160MT<br>180MT||700<br>160<br>180|60000<br>2400<br>3800|245000<br>15000<br>25000|420000<br>25000<br>38000|120<br>26<br>26||6<br>105|||||||||||||||||||||315MT 355MT 400MMT<br>280MT 355MMT<br>250MT 315MMT<br>280MMT<br>200MT<br>180MT 225MMT||||||||||||||||||||||||||||||| |200MT||200|6000|40000|58000|27||4||||||||||||||||||||||||||160MT 200MMT<br>180MMT|||||||||||||||||||||||||| |250MT<br>280MT<br>315MT<br>355MT<br>180MMT<br>200MMT<br>225MMT<br>280MMT<br>315MMT<br>355MMT<br>400MMT<br>450MMT|MT<br>MMT|250<br>280<br>315<br>355<br>180<br>200<br>225<br>280<br>315<br>355<br>400<br>450|11500<br>16500<br>19000<br>22000<br>1650<br>2200<br>3700<br>6600<br>8600<br>13500<br>21000<br>30000|80000<br>100000<br>125000<br>160000<br>12000<br>16000<br>26000<br>47000<br>62000<br>97000<br>150000<br>220000|110000<br>150000<br>180000<br>200000<br>18000<br>23000<br>40000<br>70000<br>91000<br>140000<br>220000<br>320000|32<br>35<br>42<br>51<br>42<br>42<br>42<br>47<br>51<br>54<br>60<br>57|Peak Let-Through Current|2<br>6<br>4<br>2<br>6<br>4<br>2<br>103<br>104|||||||||||||||||||||||||||||||||||80ET<br>63ET<br>56ET|||||||||160EET<br>140EET<br>110EET<br>90EET|||||||| |500MMT<br>560MMT<br>630MMT<br>710MMT||500<br>560<br>630<br>710|42000<br>60000<br>68500<br>78000|300000<br>430000<br>500000<br>600000|450000<br>640000<br>720000<br>850000|64<br>64<br>86<br>105||4<br>6<br>102||||||||||||||||||||||||||20CT<br>16CT<br>12CT<br>10CT<br>6CT|||||||||45ET<br>40ET<br>35ET<br>32ET<br>25ET||||||||||||||||| |• Watts loss provided at rated current.||||||||2|||||||||||||||||||||||||||||||||||||||||||||||||||| |• Note: FC, 8ET, 12ET, 15ET, 20ET, 65EET and 75EET are available for replacement<br>purposes on existing equipment.<br>• See accessories on page 195.||||||||101<br>101|||2||||4||6|||102||||2||4|||6||||103||2<br>4||6|||||104||2|||4|6|||105||||2||||| |||||||||||||||||||||||Prospective Short-Circuit Current Symmetrical|||||||||||||||||||||RMS||||||||||||||||| **Data Sheet: 35785312** For product data sheets, visit www.cooperbussmann.com/datasheets/ulcsa **192** **High Speed Fuses** ## **British BS 88 — 690V: 6-710A** ## **EET 90-160A, MT 160-355A: 690V** **Time-Current Curve** ## **MMT 180-710A: 690V** ## **Time-Current Curve** **==> picture [518 x 336] intentionally omitted <==** **----- Start of picture text -----**<br> 10 [4] 10 [4]<br>6 6<br>4 4<br>2 2<br>400MMT<br>10 [3] 10 [3] 450MMT<br>6 160MT 6 500MMT<br>4 180MT 4 560MMT<br>2 200MT250MT 2 630MMT710MMT<br>10 [2] 280MT<br>315MT 10 [2]<br>64 355MT 6<br>4<br>2<br>2 180MMT<br>10 [1] 200MMT<br>6 90EET 10 [1] 225MMT<br>4 110EET 6 280MMT<br>2 140EET160EET 4 315MMT355MMT<br>10 [0] 2<br>64 10 [0]<br>6<br>2 4<br>10 [–1] 2<br>6<br>4 10 [–1]<br>2 6<br>4<br>10 [–2]<br>6 2<br>4 10 [–2]<br>2 6<br>4<br>10 [–3]<br>6 2<br>4<br>10 [–3]<br>2<br>6<br>10 [–4] 2 4 6 8 10 [2] 2 4 6 8 10 [3] 2 4 6 8 104 4<br>Prospective Current In Amps RMS 2<br>10 [–4]<br>10 [2] 2 4 6 8 10 [3] 2 4 6 8 104<br>Data Sheet: 35785313 Prospective Current In Amps RMS<br>Virtual Pre-Arcing Time In Seconds<br>Virtual Pre-Arcing Time In Seconds<br>**----- End of picture text -----**<br> **Data Sheet: 35785311** ## **Peak Let-Through Curve** **==> picture [253 x 221] intentionally omitted <==** **----- Start of picture text -----**<br> 6<br>4 710MMT630MMT<br>560MMT<br>2 500MMT450MMT<br>315MT 355MT 400MMT<br>280MT 355MMT<br>10 [5] 250MT 315MMT<br>280MMT<br>6 180MT 225MMT 200MT<br>4 160MT 200MMT180MMT<br>2<br>10 [4]<br>6<br>4<br>2<br>10 [3]<br>6<br>160EET<br>4 140EET<br>110EET<br>80ET 90EET<br>2 63ET<br>56ET<br>10 [2] 6 20CT16CT12CT10CT6CT 45ET40ET35ET32ET25ET<br>4<br>2<br>10 [1] 10 [1] 2 4 6 10 [2] 2 4 6 10 [3] 2 4 6 10 [4] 2 4 6 10 [5] 2<br>Prospective Short-Circuit Current Symmetrical RMS<br>Peak Let-Through Current<br>**----- End of picture text -----**<br> For product data sheets, visit www.cooperbussmann.com/datasheets/ulcsa **193** **High Speed Fuses** ## **British BS 88 — 690V: 6-710A** ## **FE 35-100A & FM 180-350A: 690V** ## **Time-Current Curve** **==> picture [252 x 341] intentionally omitted <==** **----- Start of picture text -----**<br> 10 [4]<br>6<br>4<br>2<br>10 [3]<br>6<br>4<br>2<br>180FM<br>10 [2] 200FM<br>6 220FM<br>4 250FM<br>280FM<br>2 315FM<br>10 [1] 350FM<br>6<br>4<br>2<br>35FE<br>10 [0] 40FE<br>6 45FE<br>4 50FE<br>63FE<br>2 71FE<br>80FE<br>10 [–1] 90FE<br>6 100FE<br>4<br>2<br>10 [–2]<br>6<br>4<br>2<br>10 [–3]<br>6<br>4<br>2<br>10 [–4]<br>2 4 6 8 10 [2] 2 4 6 8 10 [3] 2 4 6 8 104<br>Prospective Current In Amps RMS<br>Virtual Pre-Arcing Time In Seconds<br>**----- End of picture text -----**<br> ## **FEE 100-200A & FMM 400-700A: 690V** ## **Time-Current Curve** **==> picture [252 x 337] intentionally omitted <==** **----- Start of picture text -----**<br> 10 [4]<br>6<br>4<br>2<br>10 [3]<br>6<br>4<br>2<br>400FMM<br>10 [2] 450FMM<br>6 500FMM<br>4 550FMM<br>630FMM<br>2 700FMM<br>10 [1]<br>6 100FEE<br>4 120FEE<br>140FEE<br>2 160FEE<br>180FEE<br>10 [0] 200FEE<br>6<br>4<br>2<br>10 [–1]<br>6<br>4<br>2<br>10 [–2]<br>6<br>4<br>2<br>10 [–3]<br>6<br>4<br>2<br>10 [–4]<br>10 [2] 2 4 6 8 10 [3] 2 4 6 8 104<br>Prospective Current In Amps RMS<br>Virtual Pre-Arcing Time In Seconds<br>**----- End of picture text -----**<br> ## **Peak Let-Through Curve** ## **Peak Let-Through Curve** **==> picture [522 x 217] intentionally omitted <==** **----- Start of picture text -----**<br> 10 [5] 8 700FMM<br>6 6 630FMM550FMM<br>4 500FMM<br>4 450FMM<br>2 350FM 400FMM<br>315FM<br>10 [4] 6 280FM250FM225FM200FM 2<br>4 180FM<br>2 10 [4]<br>8<br>10 [3] 6<br>6<br>4 4<br>2<br>100FE<br>90FE 2<br>10 [2] 80FE<br>71FE<br>6 63FE50FE<br>4 45FE40FE 10 [3]<br>35FE 8 200FEE<br>2 180FEE<br>6 160FEE<br>10 [1] 140FEE<br>10 [1] 2 4 6 10 [2] 2 4 6 10 [3] 2 4 6 10 [4] 2 4 6 10 [5] 2 4 120FEE<br>Prospective Short-Circuit Current Symmetrical RMS 100FEE<br>2 10 [2] 2 4 6 10 [3] 2 4 6 10 [4] 2 4 6 10 [5] 2<br>Prospective Short-Circuit Current Symmetrical RMS<br>Peak Let-Through Current<br>Peak Let-Through Current<br>**----- End of picture text -----**<br> **Data Sheet: 35785292** **Data Sheet: 35785314** For product data sheets, visit www.cooperbussmann.com/datasheets/ulcsa **194**
Updated at April 29, 2026
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