Distribution Circuit on DNO fuses.

[GeoffUB]

I looked at a job recently where a distribution circuit was feeding a 3ph dist board some 10m away.

My concern is that the only protection for the cable is by the DNO fuses (Labelled at 1361 100A - sealed so unable to confirm)

Cable is 16sq 4c clipped direct and rated at 94A (Table 4E4A - BS 7671) - Therefore not meeting requirements of Overcurrent protection for the cable (although very close)

The DNO have installed their own isolator (3pole switch) and a rotary isolator (3p) has been installed by a previous sparks

as further isolation. (Unable to ascertain current rating of rotary but that is another issue)

Anyone come across this issue before and how did you resolve it? Cheapest way I can see is to get DNO to derate fuses to 60A still would provide enough for end user.

 

[Lurch]

Switch fuse within 3m of the meter.

I wouldn't do anything else else unless there was absolutely no way that this was achievable.

 

[GeoffUB]

Switch fuse within 3m of the meter.

I wouldn't do anything else else unless there was absolutely no way that this was achievable.

That would do it but is there anything against using the DNO fuses to provide OC protection?

 

[Sidewinder]

DNO rules govern what you can use their fuse for, normally nothing over 3m long.

 

[GeoffUB]

DNO rules govern what you can use their fuse for, normally nothing over 3m long.

Thanks Sidewinder,

just trying to find confirmation 'online' to show the owner but cant seem to locate .....  any ideas where I might find confirmation?

FI - The meter tails are less than 3m in length, its just the issue of protecting the 16mm 4c cable.

 

[Sidewinder]

Who is the DNO?

 

[leesparkykent]

Thanks Sidewinder,

just trying to find confirmation 'online' to show the owner but cant seem to locate .....  any ideas where I might find confirmation?

FI - The meter tails are less than 3m in length, its just the issue of protecting the 16mm 4c cable.

https://www.meteroperators.org.uk/stakeholder-info

https://www.dcusa.co.uk/Documents/Panel _043 11 Electricity Metering FAQ Doc.pdf#search=length of meter tails

The Distribution Connection and Use of System Agreement (DCUSA) is as a multi-party contract between the licensed electricity distributors, suppliers and generators of Great Britain.

 

[Evans Electric]

I'd say that isolator should have been a 63A TPN  switch fuse Geoff ....no doubt on that .