Hello. I need help. I want to chamge fuses on a musical keyboard. The fuses that were inside were 4A 250V. I bought 2 different brand packs of fuses marked 4A 250V but the fuses have a mark on them 4AL 250V. L for low breaking capacity i guess. The question is can i use these instead without ANY risk? Are they the same? Whats the breaking capacity of a fuse that doesnt mention its breaking capacity(standart)? Thanks

 

IEC Publication 60127 defines three breaking capacity
levels (interrupting rating). Low breaking capacity fuses
must pass a test of 35 amperes or ten times rated current,
whichever is greater, while enhanced breaking capacity
fuses must pass a test of 150 amperes and high breaking
capacity fuses must pass a test of 1500 amperes.

If it's on the primary side just replace with correct type.

 

Thanks for the reply, but whats the correct type? What breaking capacity a standart 4A fuse has? Enchansed?

 

Thanks for the reply, but whats the correct type? What breaking capacity a standart 4A fuse has? Enchansed?

OK what type of fuse?
http://www.farnell.com/datasheets/58287.pdf

*And don't use the L rated fuses

 

Thanks for help but i cant understand a lot from that, im new to electronics. I keep your advice for not using L rated fuses, and thanks for that i was about to try them out, and possibly damage my device.

 

Hello. I need help. I want to chamge fuses on a musical keyboard. The fuses that were inside were 4A 250V.

Is this the original fuse rating? 1000 watts for a keyboard sounds way, way too much.

Look on the keyboard. There should be information about the fuse needed. I there isn't then I suggest you find the manual for the keyboard and see what they say the replacement fuse should be.

If the fuse is internal then you may need service information to get the proper fuse. Look on-line for the manual for your model of keyboard.

If you post the make and model of your keyboard here then someone may be able to help find the manual.

 

Is this the original fuse rating? 1000 watts for a keyboard sounds way, way too much.

Look on the keyboard. There should be information about the fuse needed. I there isn't then I suggest you find the manual for the keyboard and see what they say the replacement fuse should be.

If the fuse is internal then you may need service information to get the proper fuse. Look on-line for the manual for your model of keyboard.

If you post the make and model of your keyboard here then someone may be able to help find the manual.

Hello Richardo, thanks for your reply.
4A i mean 4 ampere. The manual of the keyboard is here.
The fuses i need to replace are F3 & F4.
The problem is there is no exact parts list on the manual to see what the breaking capacity of these fuses are.

 

Something on the types of fuses available.
http://www.littelfuse.com/products/fuses.aspx
Max.

 

Can you post a photo of the original fuse and the ones you purchased as replacements? Do you know the manufacturer and type number for the replacements?

A photo of the original blown fuses can help reveal something about how they blew. Sometimes fuses that have been in service for a long time and are operated near their rating will open without a fault elsewhere. Usually if a fuse on the secondary side of a transformer blows it is because something in the circuitry that is powered had failed. Often you won't cause any further damage by trying a new fuse that blows right away, but the risk is not zero.

Low breaking capacity should be OK on the secondary of a transformer. Is there an AC line fuse somewhere that is accessible on the outside of the enclosure?

 

4A i mean 4 ampere. The manual of the keyboard is here.
The fuses i need to replace are F3 & F4.

OK. These fuses appear to be on the secondary of the transformer. Since this is low voltage I don't see that the breaking capacity is any problem. As long as you use a 250 volt fuse as the manual says there is nothing to worry about.

 

Before you replace those fuses you need to know why they failed, because fuses seldom fail for no reason. Otherwise the next fuses will also fail after a short time.