sythai

~
Arms
Apr 29, 2010
1,692
420
101,758
Devon, United Kingdom
What type of forum member are you?
Practising Electrician (Qualified - Domestic or Commercial etc)
Hi Guys

Got an Emmeti UFH manifold box we wired up a while ago, fuse inside has gone 'pop' for some reason.

Not brought this type of fuse before - clear casing, got 4a marking on PCB above.

What do I search for is it a special type ?

Thanks Sy
 

Attachments

  • IMG_6068.JPG
    IMG_6068.JPG
    514.4 KB · Views: 92
  • IMG_6067.JPG
    IMG_6067.JPG
    395 KB · Views: 84
Fuses dont 'blow' like that without reason. Looks like the effect of a short circuit!
 
Fuses dont 'blow' like that without reason. Looks like the effect of a short circuit!
I'll back to find out once got a few fuses on board... something dodgy going on there 🕵️‍♂️
Hopefully not our wiring 😂
 
thanks Dave... just curious what difference is and why they would be in glass 🤔

They are glass so you can see whether or not they are intact. However glass fuses are only suitable for low levels of fault current as the glass cannot contain much energy.
 
  • Informative
Reactions: sythai
The rating of the fuse will be marked on one of the end caps, followed by a 'F' or 'T', standing for fast or slow( time) blow respectively. Be sure to fit the right type.
That fuse looks like it's been blown by a short circuit or large overload, so do some fault finding before just trying another fuse. Things like relay contacts can be irreparably damaged if subjected to successive shocks like this.
 
The rating of the fuse will be marked on one of the end caps, followed by a 'F' or 'T', standing for fast or slow( time) blow respectively. Be sure to fit the right type.
That fuse looks like it's been blown by a short circuit or large overload, so do some fault finding before just trying another fuse. Things like relay contacts can be irreparably damaged if subjected to successive shocks like this.
just checked with Emetti F1 4a time delay - thanks for heads up
 
  • Like
Reactions: Jim_e_Jib and DPG
5x20mm fuses come in both glass (LBC = low breaking capacity) and sand-filled ceramic (HBC = high breaking capacity) body versions. The glass type is standard within equipment especially for ELV circuits where the short-circuit current might only be a few amps. It's OK to replace an LBC with an HBC of the same rating and speed, but obviously not the other way round.

With PCB markings take care not to confuse the component identifier (e.g. F2 = fuse No. 2) with the rating (e.g. F2A = 2A fast-blow.) The marking 'F1 T2.5AH' would indicate that fuse No. 1 is an HRC 2.5A slow-blow type.

FWIW the speed letters are German. F = flink = nimble, T = träge = sluggish. There are also M (medium) and FF (ultra rapid) types but they are much less common.
 
Last edited by a moderator:
5x20mm fuses come in both glass (LBC = low breaking capacity) and sand-filled ceramic (HBC = high breaking capacity) body versions. The glass type is standard within equipment especially for ELV circuits where the short-circuit current might only be a few amps. It's OK to replace an LBC with an HBC of the same rating and speed, but obviously not the other way round.

With PCB markings take care not to confuse the component identifier (e.g. F2 = fuse No. 2) with the rating (e.g. F2A = 2A fast-blow.) The marking 'F1 T2.5AH' would indicate that fuse No. 1 is an HRC 2.5A slow-blow type.

FWIW the speed letters are German. F = flink = nimble, T = träge = sluggish. There are also M (medium) and FF (ultra rapid) types but they are much less common.

Never knew that's where the speed letters came from. I always thought it was T=Time lag and F = Fast.
 

Similar threads

OFFICIAL SPONSORS

Electrical Goods - Electrical Tools - Brand Names Electrician Courses Green Electrical Goods PCB Way Electric Underfloor Heating Electrician Courses Heating 2 Go Electrician Workwear Supplier
These Official Forum Sponsors May Provide Discounts to Regular Forum Members - If you would like to sponsor us then CLICK HERE and post a thread with who you are, and we'll send you some stats etc

Advert

Daily, weekly or monthly email

Thread starter

sythai

Arms
~
Joined
Location
Devon, United Kingdom
What type of forum member are you?
Practising Electrician (Qualified - Domestic or Commercial etc)

Thread Information

Title
Where do i get one of these please ?
Prefix
N/A
Forum
UK Electrical Forum
Start date
Last reply date
Replies
13

Advert

Thread statistics

Created
sythai,
Last reply from
sythai,
Replies
13
Views
1,923

Advert