Service cable, service head, meter tails

[Alessandro]

Hello, I looked everywhere but I'm still not 100% sure about the difference between:

• service cable,
  
• service head,
  
• meter tails.
  

I thought the service head was the bit of cable between the meter and the main CCU, but then what are the meter tails?

I've got 17th Edition tomorrow, good luck to me. :Salute

 

[Andy™]

service cable is the DNO supply coming in.

service head is the box on the end of above with the fuses.

meter tails are between the service head and meter, then meter to CU / switch fuse etc

 

[leesparkykent]

service cable is the cable entering the property from the network usually underground but sometimes over head.

service head is the cutout that the service cable enters which has a fuse to protect the distributors equipment.

meter tails are the cables that come from the service head to the meter and from the meter to the consumer unit. Usually insulated and sheathed singles.

 

[eodneil]

What the guys said above and here is an image to help

 

[Sharpend]

Ah now that's what I thought until today! Apparently that is not the case on a multi occupancy building. Have found out today that we have to install a ryefield board direct to service head then the meters are taken from there. So we are effectively responsible for the tails from the service head to the ryefield and to the meters and the meters to the CU, the dno responsibility stops at the service head. The meter monkey responsibility is purely the meter. 

Oh well everyday is a school day.

 

[Alessandro]

Thank you guys, clear and concise as always, and a nice picture.

 

[Tony S]

Ah now that's what I thought until today! Apparently that is not the case on a multi occupancy building. Have found out today that we have to install a ryefield board direct to service head then the meters are taken from there. So we are effectively responsible for the tails from the service head to the ryefield and to the meters and the meters to the CU, the dno responsibility stops at the service head. The meter monkey responsibility is purely the meter. 

Oh well everyday is a school day.

You need to read UKPN EDS 08-0143 regarding ownership boundaries.

 

[Sharpend]

Yes thank you Tony, I have been studying that very document tonight. Makes for interesting reading if you've not come across the situation before. 

We're apparently a BNO aswell now! 

What o find interesting is the slight subtle changes the individual DNO's put on their versions of the document. 

(Yes I know sad that I should read all the DNO's copies as well)

 

[phil d]

The worrying thing for me is that someone is about to sit an exam and doesn't know their way around the system.

 

[SLIPSHOD & SLAPDASH]

Ah now that's what I thought until today! Apparently that is not the case on a multi occupancy building. Have found out today that we have to install a ryefield board direct to service head then the meters are taken from there. So we are effectively responsible for the tails from the service head to the ryefield and to the meters and the meters to the CU, the dno responsibility stops at the service head. The meter monkey responsibility is purely the meter. 

Oh well everyday is a school day.

This is nothing new, its always been the case even pre-war. The  building owners have to put the infrastructure in and its adopted by the supplier, but  they take no responsibility  for its maintenance or replacement.

 

[Sharpend]

well it's strange cos everywhere else when we've done blocks of flats the dno have put everything in Upto the meter? 

I think also now the dno do not adopt it in all circumstances? 

 

[Alessandro]

The worrying thing for me is that someone is about to sit an exam and doesn't know their way around the system.

I wouldn't worry too much about people like me who study and ask questions when they don't know, and keep reading and studying to learn as much as possible. I would worry about all these electricians who know, but are not bothered to work properly, or who don't know and don't care.

I had this guy in class who said that a ring final ciruit wouldn't work for a lighting circuit. "It wouldn't work, how can it work, ring finals are only for power circuits". And he's been working in the sector for years. I tried to explain to him why it would indeed work (we passed science together after all) and he didn't want to listen, he simply shook his head mumbling something about his experience. This other guy said that he puts tape on switchgear to isolate circuits, so I explained to him that he is supposed to do safe isolation in a different way and the repy was "nobody does it, who cares". Then laughed. This worries me.

Anyway I passed with 100%, the first person to ever get 100% in this place. I think I'm doing well.

 

[Sharpend]

Well done fella. 

 

[apprentice87]

Well done from me too!!!!

john...

 

[eodneil]

Well done Alessandro. I believe you are still a student is that correct? If so then you are not expected to know everything otherwise there would be no need in doing the training and revising for an exam. You have done the right thing in researching your answer to understand it properly. I regularly tell my students that "No question is a stupid question in the classroom", this encourages them to ask questions rather than shy away and not understand something.

The beauty about this trade is that there is always something new to learn no matter how old and experienced you are.

Neil

 

[Alessandro]

Well done Alessandro. I believe you are still a student is that correct? If so then you are not expected to know everything otherwise there would be no need in doing the training and revising for an exam. You have done the right thing in researching your answer to understand it properly. I regularly tell my students that "No question is a stupid question in the classroom", this encourages them to ask questions rather than shy away and not understand something.

The beauty about this trade is that there is always something new to learn no matter how old and experienced you are.

Neil

Thank you Sharpend and apprentice87!

Yes I'm still a student, hated by my teacher because I ask too many questions. That's why sometimes I have to come here and ask questions (and I always try to find the answers first, books + Internet usually does the trick). I totally agree about your consideration about this trade, I know I've seen only a minute fraction of it so far and this makes it even more interesting.

 

[Tony S]

I had this guy in class who said that a ring final ciruit wouldn't work for a lighting circuit. "It wouldn't work, how can it work, ring finals are only for power circuits". And he's been working in the sector for years. I tried to explain to him why it would indeed work (we passed science together after all) and he didn't want to listen, he simply shook his head mumbling something about his experience.

Well done.

Regarding the lighting in a ring, the very few houses I’ve rewired have all had rings for the lights. Through the company I worked for cable was all but free so it couldn’t eat in to my non-existent profit (bloody families). Six houses in 40 years was five too many for me, the first was my own.

It’s just a long standing practice that is stuck permanently in peoples minds as “the only way”.

 

[leesparkykent]

well it's strange cos everywhere else when we've done blocks of flats the dno have put everything in Upto the meter? 

I think also now the dno do not adopt it in all circumstances? 

Its been done like this for a few years round my way. Most recent one I've done which I completed a few weeks ago for a block of 19 flats. 400A Glasgow fused switch that comes off the head, from fused switch to ryefield, ryefield to meters, meters to switch fuses which the swa's are glanded off into.

 

[Sharpend]

Which dno? 

 

[leesparkykent]

Which dno? 

UKPN.