N
nrbspark
Hi Guys my question is with relation to the adiabatic equation, I am aware that the following is true.
S = Size of earth bonding conductor required.
I = pfc in amps.
t = disconnection time in seconds.
K = values in table 43.1.
If I am trying to work out if a 6mm gas and water bond is adequate on a TN-C-S system where in the regs do I find the following.
1. disconnection time (I presume it is for the main incomer fuse) which in this case is 80 amp BS1361.
2. What cable am I wanting the K value for and how do I find its characteristics if it was not installed by me.
Any help appreciated guys![Smile :) :)](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
If someone could do a working calculation it would be fantastic. pfc on this job is 2.4 KA.
Just to add I always upgrade the gas and water bonds if I am asked to change a consumer unit but in this case it is almost impossible without major disruption which the customer wants to avoid.
Also am I right in thinking that if it was a TN-S system then I would have to upgrade the gas and water earths to 10mm.
S = Size of earth bonding conductor required.
I = pfc in amps.
t = disconnection time in seconds.
K = values in table 43.1.
If I am trying to work out if a 6mm gas and water bond is adequate on a TN-C-S system where in the regs do I find the following.
1. disconnection time (I presume it is for the main incomer fuse) which in this case is 80 amp BS1361.
2. What cable am I wanting the K value for and how do I find its characteristics if it was not installed by me.
Any help appreciated guys
If someone could do a working calculation it would be fantastic. pfc on this job is 2.4 KA.
Just to add I always upgrade the gas and water bonds if I am asked to change a consumer unit but in this case it is almost impossible without major disruption which the customer wants to avoid.
Also am I right in thinking that if it was a TN-S system then I would have to upgrade the gas and water earths to 10mm.