<p>The fuse rating is same as described on the board - so that shall be no issue with it.</p>

<p><strong>My main concern is why the fuse is down?</strong></p>

<p>Was there a short-circuit? As this is mains fuse - that suggest a big-bang, so, please check carefully hot-end and bed heater connections before restarting the device, to avoid replacing another fuse.</p>

CC BY-SA 4.0
2018-07-07T21:38:28.403Z
Especially check the leads to the bed heater and the solder joints on it. Find a way to provide strain relief to the wires so the flexing doesn't take place at the solder point. Make sure your hot end wires are insulated at their solder joints too.
John Deters
CC BY-SA 4.0
2018-07-06T03:16:11.713Z
2018-07-06T03:16:11.713Z
profesor79
<p>To add to the answer of <em>@profesor79</em> (which you <strong>absolutely need to address first</strong> (find the cause why it blew); else the fuse might blow again), you might be interested in installing fuse clamps. As <em>@fred_dot_u</em> mentions:</p>

<blockquote>
  <p>use caution when soldering leads to the fuse that you do not de-solder
  the internal fuse from the caps</p>
</blockquote>

<p>is that if you incorrectly solder the fuse, you might de-solder the caps, soldering the clamps is easier.</p>

<p><em>Example of fuse clamp:</em><br>
<a href="https://i.sstatic.net/HwRFQ.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/HwRFQ.jpg" alt="5 mm fuse clamp"></a></p>

CC BY-SA 4.0
2018-07-06T09:58:49.330Z
as long as there is a place on the board and drilling holes for pins will not cut other paths  the board.
profesor79
CC BY-SA 4.0
2018-07-06T14:31:30.053Z
@profesor79 I would just cut off one leg and insert in the existing hole, no drilling necessary. Anyway, what I actually would do is buy a new supply (if I'm unsure about the reason why it blew).
0scar
CC BY-SA 4.0
2018-07-06T06:55:38.613Z
2018-07-06T06:55:38.613Z
0scar
<p>A little backstory to help you understand the situation.  I put the 3D printer together and turned it on and everything seemed fine until I started printing.  It didn't even get the first layer down when the screen reset and so did the print.  I didn't think anything of it, I just went back and tried again, but this time right when I pressed start, the fuse blew.  </p>

<p>I have done some research on the issue and haven't had any luck besides recommendations for putting in a secondary fuse before the power supply (which I will be doing in the near future).  As for now though, my plan is to just replace the power supply fuse if possible.  I went to the hardware store and picked up a Bussmann T5AL/250V fuse (photo attached below) and before I put it in, I just want to make sure this is the correct fuse and I'm not going to kill the entire printer this time.  </p>

<p><em>Picture showing the internals of the power supply unit:</em></p>

<p><a href="https://i.sstatic.net/fYGTI.jpg" rel="nofollow noreferrer" title="PSU, cover removed showing fuse"><img src="https://i.sstatic.net/fYGTI.jpg" alt="PSU, cover removed showing fuse" title="PSU, cover removed showing fuse"></a></p>

<p><em>Picture of the fuse I bought:</em></p>

<p><a href="https://i.sstatic.net/QU6dU.jpg" rel="nofollow noreferrer" title="Picture of the fuse I bought"><img src="https://i.sstatic.net/QU6dU.jpg" alt="Picture of the fuse I bought" title="Picture of the fuse I bought"></a></p>

<p>Any and all help is very much appreciated because as you might expect, I'm not too happy with the printer so far.</p>

CC BY-SA 4.0
2018-07-06T01:39:36.583Z
use caution when soldering leads to the fuse that you do not de-solder the internal fuse from the caps.
fred_dot_u
CC BY-SA 4.0
2018-07-06T07:00:05.913Z
Hi Kyle, welcome to 3D Printing.SE! My first printer was also the Anet A8. Although not the best printer around you can make the printer a lot better than standard out of the box. Mine is doing very great prints now. As a caution, be very careful when tinkering with the power supply! Please let us know why you think the fuse blew. Is there any action you know of that may have triggered this? Short circuit, power peak, etc.
0scar
CC BY-SA 4.0
2018-07-06T07:15:58.237Z
If you are not 100% confident of what you're doing, you have no business messing with the internals of a power supply. You should buy a new power supply.
Tom van der Zanden
<anet-a8><switching-power-supply>
Anet A8 (Prusa i3) Power Supply Fuse
kyle thode
# Anet A8 (Prusa i3) Power Supply Fuse

(Asked by: username_0 on 2018-07-06)

A little backstory to help you understand the situation. I put the 3D printer together and turned it on and everything seemed fine until I started printing. It didn't even get the first layer down when the screen reset and so did the print. I didn't think anything of it, I just went back and tried again, but this time right when I pressed start, the fuse blew.

I have done some research on the issue and haven't had any luck besides recommendations for putting in a secondary fuse before the power supply (which I will be doing in the near future). As for now though, my plan is to just replace the power supply fuse if possible. I went to the hardware store and picked up a Bussmann T5AL/250V fuse (photo attached below) and before I put it in, I just want to make sure this is the correct fuse and I'm not going to kill the entire printer this time.

*Picture showing the internals of the power supply unit:*

[![PSU, cover removed showing fuse](https://i.sstatic.net/fYGTI.jpg "PSU, cover removed showing fuse")](https://i.sstatic.net/fYGTI.jpg "PSU, cover removed showing fuse")

*Picture of the fuse I bought:*

[![Picture of the fuse I bought](https://i.sstatic.net/QU6dU.jpg "Picture of the fuse I bought")](https://i.sstatic.net/QU6dU.jpg "Picture of the fuse I bought")

Any and all help is very much appreciated because as you might expect, I'm not too happy with the printer so far.

**Tags:** anet-a8, switching-power-supply

> **Comments:**
> **username_1**: use caution when soldering leads to the fuse that you do not de-solder the internal fuse from the caps.  
> **username_2**: Hi username_0, welcome to 3D Printing.SE! My first printer was also the Anet A8. Although not the best printer around you can make the printer a lot better than standard out of the box. Mine is doing very great prints now. As a caution, be very careful when tinkering with the power supply! Please let us know why you think the fuse blew. Is there any action you know of that may have triggered this? Short circuit, power peak, etc.  
> **username_3**: If you are not 100% confident of what you're doing, you have no business messing with the internals of a power supply. You should buy a new power supply.  

---

## 2 answers

### Answer by username_4 on 2018-07-06. Score: 4

The fuse rating is same as described on the board - so that shall be no issue with it.

**My main concern is why the fuse is down?**

Was there a short-circuit? As this is mains fuse - that suggest a big-bang, so, please check carefully hot-end and bed heater connections before restarting the device, to avoid replacing another fuse.

> **Comments:**
> **username_5**: Especially check the leads to the bed heater and the solder joints on it. Find a way to provide strain relief to the wires so the flexing doesn't take place at the solder point. Make sure your hot end wires are insulated at their solder joints too.  

---

### Answer by username_2 on 2018-07-06. Score: 1

To add to the answer of *@username_4* (which you **absolutely need to address first** (find the cause why it blew); else the fuse might blow again), you might be interested in installing fuse clamps. As *@fred\_dot\_u* mentions:

> use caution when soldering leads to the fuse that you do not de-solder
> the internal fuse from the caps

is that if you incorrectly solder the fuse, you might de-solder the caps, soldering the clamps is easier.

*Example of fuse clamp:*  
[![5 mm fuse clamp](https://i.sstatic.net/HwRFQ.jpg)](https://i.sstatic.net/HwRFQ.jpg)

> **Comments:**
> **username_4**: as long as there is a place on the board and drilling holes for pins will not cut other paths  the board.  
> **username_2**: @username_4 I would just cut off one leg and insert in the existing hole, no drilling necessary. Anyway, what I actually would do is buy a new supply (if I'm unsure about the reason why it blew).  

---

