# Fuse, Surface Mount, 4 A, Time Delay, 250 V, 4818 [1245 Metric], 1245UMFT Series

![Product image](https://novapart.co/image/farnell:3929044RL/)

**URL**: https://novapart.co/products/TR-1245UMFT4-R/fuse-surface-mount-4-a-time-delay-250-v-4818-1245
**SKU**: TR-1245UMFT4-R
**Manufacturer**: EATON BUSSMANN
**Category**: Circuit Protection || Fuses & Fuse Accessories || Fuses || SMD Fuses
**Price**: €0.4210
**Stock**: 1000+
**Lead Time**: 99 days (indicative)

## Specifications

| Parameter | Value |
|---|---|
| Svhc | To Be Advised |
| Fuse Current | 4A |
| Product Range | 1245UMFT Series |
| Fuse Case Style | 4818 [1245 Metric] |
| Voltage Rating Vac | 250V |
| Voltage Rating Vdc | - |
| Blow Characteristic | Time Delay |
| Breaking Capacity Current Ac | 100A |
| Breaking Capacity Current Dc | - |

## Datasheet

📄 [Download PDF](https://novapart.co/datasheet/farnell:3929044RL/)

Technical Data **ELX1119** Effective December 2021 

## 1245UMFT Universal modular fuse, time delay, SMT 

## **Applications** 

- Power supply 

- White goods 

- Lighting system 

- Industrial equipment 

- Lighting ballast 

- AC/DC adaptor primary protection 

- Medical Equipment 

## **Product features** 

- 12.5 x 4.8 x 4.8 mm surface mount package 

- Complies with IEC60127-4 Universal modular fuse-links 

   - Battery protection 

   - LCD monitor 

   - Office electronic equipment 

   - Industrial equipment 

- Time delay 

- 250 Vac Voltage rating brick fuse 

- Ceramic square body with end cap design 

- Moisture sensitivity level (MSL): 1 

## **Agency information** 

cURus Recognition file number: (Pending) 

## **Environmental compliance** 

**==> picture [22 x 22] intentionally omitted <==**

**----- Start of picture text -----**<br>
HALOGEN<br>HF<br>FREE<br>**----- End of picture text -----**<br>


## **Ordering part number** 

The ordering code is the packaging code and part number replacing the “.” with a “-” i.e. 1.25=1-25 

**TR - 1245UMF  T x-xx - R** 

**==> picture [54 x 53] intentionally omitted <==**

**----- Start of picture text -----**<br>
Packaging code<br>Family name<br>Time delay option<br>Rated current<br>RoHS<br>**----- End of picture text -----**<br>


## **Packaging prefix** 

TR- (1000 parts on a 13” diameter tape and reel) 

1245UMFT Universal modular fuse, time delay, SMT 

Technical Data ELX1119 Effective December 2021 

## **Electrical characteristics** 

|||**1.25 In**||**2 In**|||
|---|---|---|---|---|---|---|
|**Amp Rating**||**minimum**||**maximum**||**10 In**|
|1.0 A ~ 6.3 A||1 hour||120 seconds||10 - 100 milliseconds|



## **Product specifications** 

||**Current**<br>**rating**|**Voltage**<br>**rating**|**Interrupting rating**<br>**@ rated voltage1**|**Typical**<br>**cold resistance2**|**Typical**<br>**voltage drop**|**Typical pre-arcing3**||
|---|---|---|---|---|---|---|---|
|**Part number**|**(A)**|**(Vac)**|**(A) Vac**|**(mΩ)**|**(mV)**|**I²t (A2s)**|**Part marking**|
|1245UMFT1-R|1|250|100|118|165|2.4|BUSS T1AL AC250V|
|1245UMFT1-25-R|1.25|250|100|85|150|5|BUSS T1.25AL AC250V|
|1245UMFT1-6-R|1.6|250|100|62|140|7.5|BUSS T1.6AL AC250V|
|1245UMFT2-R|2|250|100|42|116|11|BUSS T2AL AC250V|
|1245UMFT2-5-R|2.5|250|100|33|115|15|BUSS T2.5AL AC250V|
|1245UMFT3-15-R|3.15|250|100|23.6|95|31|BUSS T3.15AL AC250V|
|1245UMFT4-R|4|250|100|20|125|62|BUSS T4AL AC250V|
|1245UMFT5-R|5|250|100|14.5|100|105|BUSS T5AL AC250V|
|1245UMFT6-3-R|6.3|250|100|11|100|160|BUSS T6.3AL AC250V|



1. AC Interrupting rating (measured at rated voltage, >95% power factor); 

2. Typical cold  resistance is measured at <10% of rated current in ambient temperature of +25 °C 

3. Typical pre-arcing I[2] t are measured at 8 ms 

**Dimensions- mm** Drawing not to scale 

## **Recommended pad layout** 

Recommended trace thickness is 35 um; the minimum trace width is 5 mm Recommended stencil thickness is 0.15 mm 

## **General specifications** 

Operating temperature: -40 °C to +125 °C with proper derating factor applied 

Thermal shock: MIL-STD-202,Method 107, -40 °C to +125 °C, number of cycles 1000,  transfer time 20 seconds, dwell time 15 minutes air-air. Mechanical shock: MIL-STD-202, Figure 1 of Method 213, Condition C, 100 g, 6 ms 

Vibration: MIL-STD-202 Method 201, 2 hours each of 3 orientations. Test from 10 - 55 Hz in 1 minute Resistance to solder heat: MIL-STD-202 Method 210, Solder temperature +260 °C ± 5 °C,solder immersion time 10 s ± 5 s Solderability test: J-STD-002, Method B1 Steam aging 1 hour, Solder temperature +255 °C ± 5 °C, solder immersion time 5 s Humidity bias: MIL-STD-202 Method 103, 1000 hours +85 °C/85% RH. Specified conditions: 10% of operating power. Breaking capacity: Spec, Ambient Temperature +25 °C + -5 °C UMF-6.3 A: 250 Vac, 100 A High temperature operating life: MIL-STD-202 Method 108, Condition D, Steady state +70 °C at 60% rated current. 

2 

www.eaton.com/electronics 

Technical Data ELX1119 Effective December 2021 

## 1245UMFT Universal modular fuse, time delay, SMT 

## **Packaging information - mm** 

1000 parts per 13” diameter reel (EIA-481 compliant) Drawing not to scale 

|**Dimension**|**millimeter**|
|---|---|
|W|24.00|
|F|11.50|
|E1|1.75|
|E2|N/A|
|P0|4.00|
|P1|8.00|
|P2|2.00|
|DO|1.50|
|D1<br>A0<br>~~—_~~|1.50<br>4.85|
|B0|12.75|
|K0|4.90|
|T|0.40|



## **Reel dimension- mm** 

||**Dimension**|**millimeter**|
|---|---|---|
||A|330 ± 1|
||B|2.5 ± 0.2|
||C|13.5 ± 0.2<br>~~a~~|
||D|N/A|
|N<br>~~ee~~||100 ± 0.5|
|W1<br>24.8 ± 0.5<br>W2<br>30.4 max<br>~~OH~~|||
||W3|N/A|



3 

www.eaton.com/electronics 

1245UMFT Universal modular fuse, time delay, SMT 

Technical Data ELX1119 Effective December 2021 

## **Temperature derating curve** 

**==> picture [202 x 111] intentionally omitted <==**

**----- Start of picture text -----**<br>
0.9<br>08<br>07<br>50 -40 -30 -20 -10 0 10 20 30 40 50<br>Temperature (°C)<br>Derating factor<br>**----- End of picture text -----**<br>


## **Current vs. time curve** 

**==> picture [8 x 59] intentionally omitted <==**

**----- Start of picture text -----**<br>
Time (seconds)<br>**----- End of picture text -----**<br>


**==> picture [42 x 8] intentionally omitted <==**

**----- Start of picture text -----**<br>
Current (A)<br>**----- End of picture text -----**<br>


4 

www.eaton.com/electronics 

Technical Data ELX1119 Effective December 2021 

1245UMFT Universal modular fuse, time delay, SMT 

## **Wave solder profile** 

|**Temperature**<br>Tsmin<br>Tsmax<br>Tstyp<br>Tp<br>**Reference EN 61760-1:2006**<br>**Profile feature**|tp<br>First Wave<br>Second Wave<br>Preheat area<br>Cool down area|tp<br>First Wave<br>Second Wave<br>Preheat area<br>Cool down area|
|---|---|---|
||**Time**||
|Preheat                    • Temperature min.|(Tsmin)|100 °C<br>100 °C|
|• Temperature typ. (Tstyp)||120 °C<br>120 °C|
|• Temperature max. (Tsmax)||130 °C<br>130 °C|
|• Time (Tsmin to Tsmax) (ts)||70 seconds<br>70 seconds|
|D preheat tomax Temperature||150 °C max.<br>150 °C max.|
|Peak temperature (TP)*||235 °C – 260 °C<br>250 °C – 260 °C|
|Time at peak temperature (tp)||10 seconds max<br>5 seconds max each wave<br>10 seconds max<br>5 seconds max each wave|
|Ramp-down rate||~ 2 K/s min<br>~3.5 K/s typ<br>~5 K/s max<br>~ 2 K/s min<br>~3.5 K/s typ<br>~5 K/s max|
|Time 25 °C to 25 °C||4 minutes<br>4 minutes|



5 

www.eaton.com/electronics 

1245UMFT Universal modular fuse, time delay, SMT 

Technical Data ELX1119 Effective December 2021 

## **Solder reflow profile** 

**==> picture [328 x 182] intentionally omitted <==**

**----- Start of picture text -----**<br>
TP<br>TC -5°C<br>Max. Ramp Up Rate = 3°C/s tP<br>Max. Ramp Down Rate = 6°C/s<br>TL Preheat t |<br>ee" A<br>Tsmax<br>Tsmin<br>   ts<br>25°C<br>Time 25°C to Peak  Time<br>Temperature<br>**----- End of picture text -----**<br>


## **Table 1 - Standard SnPb solder (Tc)** 

|**Package**<br>**thickness**<br>**Volume**<br>**mm3**<br>**<350**<br>**Volume**<br>**mm3**<br>**≥350**|
|---|
|<2.5 mm<br>235 °C<br>220 °C<br>≥2.5 mm<br>220 °C<br>220 °C<br>~~a~~|



## **Table 2 - Lead (Pb) free solder (Tc)** 

|**Package**<br>**thickness**||**Volume**<br>**mm3**<br>**<350**||**Volume**<br>**mm3**<br>**350 - 2000**||**Volume**<br>**mm3**<br>**>2000**|
|---|---|---|---|---|---|---|
|<1.6 mm||260 °C||260 °C||260 °C|
|1.6 – 2.5 mm||260 °C||250 °C||245 °C|
|>2.5 mm||250 °C||245 °C||245 °C|



## **Reference J-STD-020** 

|**Profile feature**||**Standard SnPb solder**||**Lead (Pb) free solder**|
|---|---|---|---|---|
|Preheat and soak     • Temperature min. (Tsmin)||100 °C||150 °C|
|• Temperature max. (Tsmax)||150 °C||200 °C|
|• Time (Tsmin to Tsmax) (ts)||60-120 seconds||60-120 seconds|
|Ramp up rate TL to Tp||3 °C/ second max.||3 °C/ second max.|
|Liquidous temperature (Tl)||183 °C||217 °C|
|Time (tL) maintained above TL||60-150 seconds||60-150 seconds|
|Peak package body temperature (TP)*||Table 1||Table 2|
|Time (tp)* within 5 °C of the specified classification temperature (Tc)||20 seconds*||30 seconds*|
|Ramp-down rate (Tpto TL)||6 °C/ second max.||6 °C/ second max.|
|Time 25 °C to peak temperature||6 minutes max.||8 minutes max.|



* Tolerance for peak profile temperature (Tp) is defined as a supplier minimum and a user maximum. 

Life Support Policy: Eaton does not authorize the use of any of its products for use in life support devices or systems without the express written approval of an officer of the Company. Life support systems are devices which support or sustain life, and whose failure to perform, when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in significant injury to the user. 

Eaton reserves the right, without notice, to change design or construction of any products and to discontinue or limit distribution of any products. Eaton also reserves the right to change or update, without notice, any technical information contained in this bulletin. 

**Eaton Electronics Division** 1000 Eaton Boulevard Cleveland, OH 44122 United States Eaton.com/electronics © 2021 Eaton All Rights Reserved Printed in USA Publication No. ELX1119 BU-ELX21127 December 2021 

Follow us on social media to get the Eaton is a registered trademark. latest product and support information. All other trademarks are property of their respective owners. f/¥iinjo 



## Links

- [View this product on Novapart](https://novapart.co/products/TR-1245UMFT4-R/fuse-surface-mount-4-a-time-delay-250-v-4818-1245)
- [Request a quote for this part](https://novapart.co/quote/)
- [Supplier page](https://es.farnell.com/eaton-bussmann/tr-1245umft4-r/smd-fuse-time-delay-4a-250vac/dp/3929044RL)
---

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