Time to call it a day

[Risteard]

Fault levels in commercial are often similar to domestic with the same type of circuit protection.

And they are often much greater. If you look at the cable standards you will see that they are designed for domestic installations. You can claim that T&E in non-domestic installations is good practice all you want but it says more about you than me if you think that. It is frankly an abhorrent practice which only occurs because it is a cheap way of doing things - not because it is a good way.

 

[Ian1981]

And they are often much greater. If you look at the cable standards you will see that they are designed for domestic installations. You can claim that T&E in non-domestic installations is good practice all you want but it says more about you than me if you think that. It is frankly an abhorrent practice which only occurs because it is a cheap way of doing things - not because it is a good way.

An example would be dado trunking for a computer suite.
Where does it state and why not use twin and earth cables if seen fit.
Plenty of room in 100x 75mm trunking , capacity not exceeded to say you have to install singles is absurd

 

[Risteard]

An example would be dado trunking for a computer suite.
Where does it state and why not use twin and earth cables if seen fit.
Plenty of room in 100x 75mm trunking , capacity not exceeded to say you have to install singles is absurd

Trunking is designed for singles - not for T&E. And in Dado T&E is so inflexible as to be completely unsuitable.

 

[7029 dave]

Trunking is designed for singles - not for T&E. And in Dado T&E is so inflexible as to be completely unsuitable.

I agree on that.

 

[kingeri]

Trunking is designed for singles - not for T&E. And in Dado T&E is so inflexible as to be completely unsuitable.

Also there is no reference method B for t&e suggesting that it was not conceived originally that people would start putting it in conduit etc.

 

[Ian1981]

Trunking is designed for singles - not for T&E. And in Dado T&E is so inflexible as to be completely unsuitable.

So you wouldn't use trunking in domestic applications like trunking a twin and earth cable to a db for instance adding a circuit or if db is in a garage cables enter db on bare block work?

 

[Risteard]

Also there is no reference method B for t&e suggesting that it was not conceived originally that people would start putting it in conduit etc.

Precisely - again this is because it is not intended for non-domestic installation methods.

 

[Risteard]

So you wouldn't use trunking in domestic applications like trunking a twin and earth cable to a db for instance adding a circuit or if db is in a garage cables enter db on bare block work?

Mini-trunking is completely different to a proper metallic trunking system or dado trunking. So it's a bit of a silly point to make. There it is simply being used for tidiness and not as a containment system.

 

[Ian1981]

Also there is no reference method B for t&e suggesting that it was not conceived originally that people would start putting it in conduit etc.

There's a method B for cables 70 degree operational temp tables.
Sheathed cables

 

[Ian1981]

Mini-trunking is completely different to a proper metallic trunking system or dado trunking. So it's a bit of a silly point to make. There it is simply being used for tidiness and not as a containment system.

50 x 50 trunking is not mini trunking where the db is installed in say a garage on block work and the cables are installed in the said trunking entering the db.
Ref method B

 

[Risteard]

50 x 50 trunking is not mini trunking where the db is installed in say a garage on block work and the cables are installed in the said trunking entering the db.
Ref method B

Again, you are not talking about a containment system but merely a way of keeping the cables tidy. A containment system is completely enclosed for a start.

 

[Ian1981]

Again, you are not talking about a containment system but merely a way of keeping the cables tidy. A containment system is completely enclosed for a start.

Look to say you would try and ram in twin and earth cables in say 20mm galv conduit on a conduit system is not the correct way however to say twin earth cables can't be installed in all commercial containment if installed correctly I don't agree with

 

[Rpa07]

@Sparkhe did I mention that we bicker a lot and forget all about the original post! Electricians - like housewives sometimes! No offence @Midwest!

 

[Darkwood]

Has no one brought up the issue that the loads are in excess of 2 Kw and require independant circuits, it sounds like the OP fed a 2way board from a 32amp mcb with 2,5cable now if that was a ringmain tap off then he has breached the regulation in the fact that the designed loads are in excess of 2kw and would need their own individual circuit.
If the OP has wired it direct from its own 32amp mcb then I still think the installation is in poor design, it's been stated that these toasters are rated at 16amp so this should be the designed load value not a clamped value, we do not have enough info on the toasters to comment any further but they could be power regulated to control the heat better or the voltage to the premises may have been lower than normal that day due to network loading and VD, what would happen if that was rectified in the future thus these toasters may draw more current and possible overload the cable.

You cannot even use the fixed load regulation to allow a higher rated OCPD than the cable because the cable does not meet the specified ampage of the toasters combined so I have to agree here its a poorly design and could become dangerous, regardless of still been on the 16th edition here, this shouldn't have been design this way even if your on the 15th edition on paper.

 

[Sparkhe]

Has no one brought up the issue that the loads are in excess of 2 Kw and require independant circuits, it sounds like the OP fed a 2way board from a 32amp mcb with 2,5cable now if that was a ringmain tap off then he has breached the regulation in the fact that the designed loads are in excess of 2kw and would need their own individual circuit.
If the OP has wired it direct from its own 32amp mcb then I still think the installation is in poor design, it's been stated that these toasters are rated at 16amp so this should be the designed load value not a clamped value, we do not have enough info on the toasters to comment any further but they could be power regulated to control the heat better or the voltage to the premises may have been lower than normal that day due to network loading and VD, what would happen if that was rectified in the future thus these toasters may draw more current and possible overload the cable.

You cannot even use the fixed load regulation to allow a higher rated OCPD than the cable because the cable does not meet the specified ampage of the toasters combined so I have to agree here its a poorly design and could become dangerous, regardless of still been on the 16th edition here, this shouldn't have been design this way even if your on the 15th edition on paper.

Hi darkwood I see were you are coming from sounds about right. But I did not come off a ring main as that would have been stupid, it was from a 32amp mcb on a fuse board . So thanks for the input.