# Fuse, PCB Leaded, 500 mA, 125 V, PICO II 251 Series, 125 V, Very Fast Acting, Axial Leaded

![Product image](https://novapart.co/image/farnell:9921966/)

**URL**: https://novapart.co/products/0251.500NAT1L/fuse-pcb-leaded-500-ma-125-v-pico-ii-251-series
**SKU**: 0251.500NAT1L
**Manufacturer**: LITTELFUSE
**Category**: Circuit Protection || Fuses & Fuse Accessories || Fuses || PCB Fuses
**Price**: €0.4810
**Stock**: 1000+
**Lead Time**: 78 days (indicative)

## Description

Fuse Current:500mA; Voltage Rating VAC:125VAC; Product Range:PICO II Series; Voltage Rating V DC:125VDC; Blow Characteristic:Very Fast Acting; Fuse Case Style:Axial Leaded; Breaking Capacity Curr

## Specifications

| Parameter | Value |
|---|---|
| Svhc | No SVHC (17-Dec-2014) |
| Fuse Current | 500mA |
| Product Range | PICO II 251 Series |
| Fuse Case Style | Axial Leaded |
| Voltage Rating Vac | 125V |
| Voltage Rating Vdc | 125V |
| Blow Characteristic | Very Fast Acting |
| Breaking Capacity Current Ac | 50A |
| Breaking Capacity Current Dc | 300A |

## Datasheet

📄 [Download PDF](https://novapart.co/datasheet/farnell:9921966/)

Fuse **Datasheet** 

**251 Series** PICO[® ] II Very Fast-Acting Fuse 

## **PS E** © CA@ 

## **Description** 

The PICO® II Very Fast-Acting Fuse is designed to meet an extensive array of performance characteristics in a space-saving subminiature package. 

## **Features and Benefits** 

- Very fast-acting ■ Halogen-free available 

- Small size 

   - Wide operating temperature range 

- Wide current rating range (0.062A- 15A) ■ Low temperature re-rating 

## **Applications** 

## **Web Resources** 

Download ECAD models, order samples, and find technical recources at www.littelfuse.com/251 

Secondary protection for space constrained applications 

   - Power supply 

- Flat–panel display TV 

- LCD monitor ■ Audio/Video system 

- LCD backlight inverter ■ Lighting system 

- Office machines ■ Medical equipment 

## **Agency Approvals** 

|**Agency**<br>~~ce~~|**Agency File/Certificate Number**|**Ampere Range**<br>0.062A - 15A|
|---|---|---|
||**251 Series**<br>N/A||
|~~ce~~|N/A|0.062A - 15A|
||E10480|0.062A - 15A|
|@.|29862|0.062A - 15A|
|**PS**<br>**E**<br>Oo|PSE_NBK200416-JP1021|1A - 5A|
|A|J50158379|0.500A - 10A|
||2020970207000061|0.500A, 1A, 2A,<br>2.5A, 3A, 4A, 5A|



**Note:** See Electrical Specifications by Item table for specific approved ratings. 

## **Electrical Characteristics for Series** 

|**% of Ampere Rating**<br>100%|**Ampere Rating**<br>0.062A - 15A|**Opening Time**<br>4 Hours, Min.|
|---|---|---|
|200%|0.062A - 7A|1 Second, Max.|
||10A|3 Seconds, Max.|
||12 - 15A|10 Seconds, Max.|
|275%|0.500A, 1A, 2A,<br>2.5A,3A,4A,5A|300 msecs., Max.|
|400%|0.5A, 1A, 2A, 2.5A,<br>3A,4A,5A|30 msecs., Max.|
|1000%|0.500A, 1A, 2A,<br>2.5A,3A,4A,5A|4 msecs., Max.|



© 2024 Littelfuse, Inc. Specifications are subject to change without notice. Revised: VL 09/26/24 

**1** 

Fuse **Datasheet** 

**251 Series** PICO[® ] II Very Fast-Acting Fuse 

## **Electrical Specifications by Item** 

|**Ampere**<br>**Rating**<br>**(A)**<br>.062|**Amp**<br>**Code**<br>.062|**Ordering Number**<br>**(Std.)**<br>251.062|**Ordering Number**<br>**Max**<br>**Voltage**<br>**Rating**<br>**(V)**<br>125|**Interrupting**<br>**Rating**<br>300 A @ 125VDC<br>50A@<br>125VAC|**Nominal**<br>**Cold**<br>**Resistance**<br>**(Ohms)**<br>7.000|**Nominal**<br>**Melting**<br>**I2t (A2 sec)**<br>0.000113|**Nom**<br>**Voltage**<br>**Drop**<br>**(V)**<br>1.4|**Agency Approvals**|**Agency Approvals**|**Agency Approvals**|**Agency Approvals**|**Agency Approvals**|**Agency Approvals**|**Agency Approvals**|
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|||||||||x<br>Ms|x<br>MsCO|x<br>C~~E~~|x<br>EG|**PS**<br>**E**<br>-<br> CA|-<br>CA|-|
|.125|.125|251.125|125||1.700|0.00174|0.285|x|x|x|x|-|-|-|
|.200|.200|251.200|125||0.895|0.0048|0.345|x|x|x|x|-|-|-|
|.250|.250|251.250|125||0.665|0.0116|0.24|x|x|x|x|-|-|-|
|.375|.375|251.375|125||0.395|0.0296|0.215|x|x|x|x|-|-|-|
|.500|.500|251.500|125||0.302|0.0598|0.2165|x|x|x|x|-|x|x|
|.630|.630|251.630|125||0.205|0.08|0.188|x|x|x|x|-|-|-|
|.750|.750|251.750|125||0.175|0.153|0.176|x|x|x|x|-|x|-|
|1.00|001.|251001.|125||0.128|0.256|0.194|x|x|x|x|x|x|x|
|1.25|1.25|2511.25|125||0.100|0.390|0.2|x|x|x|x|x|-|-|
|1.50|01.5|25101.5|125||0.0823|0.587|0.21|x|x|x|x|x|x|-|
|2.00|002.|251002.|125||0.0473|0.405|0.141|x|x|x|x|x|x|x|
|2.50|02.5|25102.5|125||0.0360|0.721|0.132|x|x|x|x|x|x|x|
|3.00|003.|251003.|125||0.0295|1.19|0.131|x|x|x|x|x|x|x|
|3.50|03.5|25103.5|125||0.0240|1.58|0.1205|x|x|x|x|x|x|-|
|4.00|004.|251004.|125||0.0204|2.45|0.114|x|x|x|x|x|x|x|
|5.00|005.|251005.|125||0.0158|4.14|0.11|x|x|x|x|x|x|x|
|7.00|007.|251007.|125||0.0107|10.4|0.102|x|x|x|x|-|x|-|
|10.0|010.|251010.|125||0.0072|25.5|0.1|x|x|x|x|-|x|-|
|12.0|012.|251012.|32|300A@32VDC<br>& 50A@32VAC|0.0059|45.2|0.0878|x|x|x|x|-|-|-|
|15.0|015.|251015.|32||0.00446|68.8|0.071|x|x|x|x|-|-|-|



**Note:** Higher ampere ratings are available. Please contact Littelfuse Technical Support or your Littelfuse products representative for assistance. 

## **Temperature Re-rating Curve** 

## **Average Time Current Curves** 

## **Note:** 

**1.** Re-rating depicted in this curve is in addition to the standard derating of 25% for continuous operation. 

© 2024 Littelfuse, Inc. Specifications are subject to change without notice. Revised: VL 09/26/24 

**2** 

Fuse **Datasheet** 

## **251 Series** PICO[® ] II Very Fast-Acting Fuse 

## **Product Characteristics** 

**Materials** Encapsulated, Epoxy-coated Body 251 Series: Pure tin-coated copper wire leads **Solderability** MIL-STD-202, Method 208 MIL-STD-202, Method 211, Test Condition A (will **Lead Pull Force** withstand a 7lbs. axial pull test) **Operating** –55ºC to +125ºC (Consider re-rating) **Temperature** 

**Vibration Shock Insulation Resistance (After Opening): Moisture Resistance Resistance to Soldering Heat Flammability Rating** 

MIL-STD-202, Method 201 (10–55 Hz); Method 204, Test Condition C (55–2000 Hz at 10 G’s Peak) MIL-STD-202, Method 213, Test Condition I (100 G’s peak for 6 msecs.) MIL-STD-202, Method 302, Test Condition A (10,000 ohms minimum at 100 volts) MIL-STD-202, Method 106[Withstands 60 seconds above 200][O][C ] and up to 260ºC, maximum UL 94V–0 

## **Soldering Parameters** 

## **Recommended Process Parameters:** 

|**Wave Parameter**<br>Preheat:<br>(Depends on Flux Activation Temperature)|**Lead-Free Recommendation**<br>**for 251 Series only**<br>(Typical Industry Recommendation)|
|---|---|
|Temperature Minimum:|100°C|
|Temperature Maximum:|150°C|
|Preheat Time:|60-180 seconds|
|Solder Pot Temperature:|260°C Maximum|
|Solder Dwell Time:|2-5 seconds|



## **Packaging** 

|**Packaging Option**<br>*T1: 52.4mm (2.062")<br>Tape and Reel|**Packaging**<br>**Specification**<br>EIA v296|**Quantity &**<br>**Packaging Code**<br>Please refer to<br>available quantities<br>above in "Part<br>Numbering<br>System”|
|---|---|---|



The default lead length for both ammo pack and loose pack is T1 for 251 and is T3 for 253. 

## **Notes:** 

**Recommended Hand Soldering Parameters:** 

Solder Iron Temperature: 350°C +/- 5°C Heating Time: 5 seconds max. 

- T1 dimension is defined as the length of the component between the two tapes. The full component length is 62.7mm (2.468"). **T1 length is for 251 series only.** 

**Note:** These devices are not recommended for IR or Convection Reflow process 

## **Dimensions** 

## **Part Numbering System** 

**Disclaimer Notice** - Information furnished is believed to be accurate and reliable. However, users should independently evaluate the suitability of and test each product selected for their own applications. Littelfuse products are not designed for, and may not be used in, all applications. Read complete Disclaimer Notice at: www.littelfuse.com/disclaimer-electronics. 

© 2024 Littelfuse, Inc. Specifications are subject to change without notice. Revised: VL 09/26/24 

**3** 



## Links

- [View this product on Novapart](https://novapart.co/products/0251.500NAT1L/fuse-pcb-leaded-500-ma-125-v-pico-ii-251-series)
- [Request a quote for this part](https://novapart.co/quote/)
- [Supplier page](https://es.farnell.com/littelfuse/0251-500nat1l/fuse-quick-blow-500ma/dp/9921966)
---

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