I have read a few posts about the supply to bathroom fans needing to be fused down to 3A and I have been working on approving a new product with BSI.
Putting these two things together I am wondering if the requirement for the addition fuse with skme manufacturers is actually to make the product into an installation category II product. This has a number of effects on things like creepage and clearance distances on the traces on any PCB etc.
Interestingly swapping the 6A MCB to a 3A wont change the category but putting a 3A fuse after the 6A MCB will even though you have no idea which will blow first in the event of a fault in some situations.
The test engineer I was working with was happy that an FCU puts the device into CAT II even though its still feeding fixed equipment.
Installation categories are also known as over voltage categories and the lower the category the lower the transient voltage the equipment needs to cope with.
Installation categories are defined in iec 60664-1 and shown here:
Has anyone got a fan manual that mentions the installation / overvoltage category used for the CE marking of the product?
Probably a boring post but I guess it may be of use to someone!
Putting these two things together I am wondering if the requirement for the addition fuse with skme manufacturers is actually to make the product into an installation category II product. This has a number of effects on things like creepage and clearance distances on the traces on any PCB etc.
Interestingly swapping the 6A MCB to a 3A wont change the category but putting a 3A fuse after the 6A MCB will even though you have no idea which will blow first in the event of a fault in some situations.
The test engineer I was working with was happy that an FCU puts the device into CAT II even though its still feeding fixed equipment.
Installation categories are also known as over voltage categories and the lower the category the lower the transient voltage the equipment needs to cope with.
Installation categories are defined in iec 60664-1 and shown here:
Has anyone got a fan manual that mentions the installation / overvoltage category used for the CE marking of the product?
Probably a boring post but I guess it may be of use to someone!
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