loop impedence

[lionelmcc]

I have to update to 17th so I was looking at some mock exam papers ( domelec),. One of them asked this question and quoted the relevant regulation for the answer:


The maximum earth fault loop impedance for stationary equipment controlled by a
BS88 general purpose 32 A fuse as part of a TN system is
a 1.09 Ω
b 1.14 Ω
c 1.04 Ω IEE regs 411.4.6 Table 41.2 (page 48)
d 1.20.Ω
In addition to the

Am I missing something?
By stationary do we mean “fixed"? or not?
If so then the relevant table would be 41.4 (5s disconnection?)

Someone put me right – I’m confused - or perhaps, in this case, fuse conned ?????

 

[makawhite]

OSG pg 21.

For TN systems A disconnection time of no more than 0.4 s is required for final circuits with a rating not exceeding 32A. 5s disconnection time is required for final circuits exceeding 32A