Does 1 Amp make that big of a difference in glass fuses?

[klm123]

Hello, I have a Chinese 90w laser engraver, and recently the power supply went out. While operating, I heard a pop, and when I disassembled, I found one of the transistors had shorted with a black mark. I have since replaced this power supply, and replaced the fuse that is located in the receptacle that the electrical plug plugs into the back of the laser. The fuse that I replaced, was a 250v 3A glass fuse, and the one that I put in turned out to be a 250v 2A. It blew right away. I'm hoping that the 1A difference is the culprit, and not another electrical component, for these lasers have several. I will be installing a 3A 250v later today, but just wanted to get some opinions. Thanks. Oh, and there were no instructions that came with my laser, and since has been discontinued, so any available information on this is slim to none.

 

[DPG]

It's possible. But what is more likely is that it may be a quick blow rather than time lag fuse. Does the fuse that was fitted originally have a T next to the current rating?

 

[klm123]

It's possible. But what is more likely is that it may be a quick blow rather than time lag fuse. Does the fuse that was fitted originally have a T next to the current rating?

Yes. It has ‘T6.3AL.250v’. And I just tried a fuse that has just ‘3A250v’ on it, and it also blew as soon as I turn the key on.

 

[klm123]

Yes. It has ‘T6.3AL.250v’. And I just tried a fuse that has just ‘3A250v’ on it, and it also blew as soon as I turn the key on.

Now that I look closely, it may be a 6.3A fuse?

 

[DPG]

Try again with the correct fuse. But bear in mind there still may be a fault. Let us know what happens

 

[klm123]

Try again with the correct fuse. But bear in mind there still may be a fault. Let us know what happens

Just ordered a 10 pack. They are T6.3AL.250v. So the 'T', and the 'L' stands for 'time lag'? Will try this weekend after they come in. Fingers crossed! Thanks for the input. I will let you know.

 

[DPG]

The T

Just ordered a 10 pack. They are T6.3AL.250v. So the 'T', and the 'L' stands for 'time lag'? Will try this weekend after they come in. Fingers crossed! Thanks for the input. I will let you know.

The T is 'slow blow'. Yes, keep us posted.

 

[klm123]

The T


The T is 'slow blow'. Yes, keep us posted.

Just tried the laser with the right fuse, and it is back in action! I will have to do some additional runs on it just to make sure nothing else is damaged, but thanks to you, I was able to get it going again! Cheers!

 

[DPG]

Just tried the laser with the right fuse, and it is back in action! I will have to do some additional runs on it just to make sure nothing else is damaged, but thanks to you, I was able to get it going again! Cheers!

Nice one. And thanks for letting us know.

 

[brianmoooore]

The 'L' stands for low break capacity. I know this because I came across a blown wired in fuse in a bit of equipment two days ago, marked F1AL250V. Didn't know what the L was for, so did the research.