Hi all, could someone remind me what the instantaneous tripping current for semi-enclosed 3036 fuses is. (How many times their rating?). I can`t remember where i seen it.Also on page 283 of the NICEIC Domestic periodic Inspection, Testing and Reporting, it states that it is the 5 second operating current for an overcurrent protective device (taken from the time/current characteristics of the device) that is used when you are deciding upon whether to supplementary bond or not. I thought that you used 0.4 now
Many thank`s
Time/Current characteristics graphs start at page 244 in BRB
3036's on pages 245 & 246... Is this what you wanted?
NIC DOM PIR book Page283...
It does NOT state:
"it states that it is the 5 second operating current for an overcurrent protective device ............. . I thought that you used 0.4 now"
This section starts on page 282, it is referring to identifying if additional supp bonding is requied....
where the opening sentence says that it is installations wired prior to BS7671 2008.
The example they give in point 1 Pg 283 is verifying a metal bathroom light on
an older installation wired with a 3036 fuse whereby the 5s dis time was the appropriate installation spec...
It is not saying current new installations to 17th ed 2008 should have 5s dis time.
They are testing what the potential touch voltage between the metallic parts of the bathroom could be under a lighting fault on this older pre 17th installation...
so the worst case should be a 5s dis time before any potential voltage rise will be disconnected by the 3036 fuse.
THIS BOOK IS PERIODIC INSPECTION TESTING...
not testing a new installtion you have just re-wired.
So older practices and compliance with previous versions of regs need to be verified such as to ascertain if its a "complies with older version but NOT unsafe" as compared to a Urgent action required.
much like you wouldn't fail an old installation cus you can't read the RCD operating times on the light circuit, when there was NO RCD needed when it was originally installed.!
:|
