Ring main with IT equipment

[bramboy]

It looks like 4mm twin and earth ring mains to get all coductors upto 10mm. The powers that be have wanted this on all rings for a while with the highly insulated structures we come against nowadays

 

[sparks1234]

It looks like 4mm twin and earth ring mains to get all coductors upto 10mm. The powers that be have wanted this on all rings for a while with the highly insulated structures we come against nowadays

How does that work then, 4 + 4 + 1-5 =9-5mm

 

[marksparky]

i think he means 4+4+2.5=10.5

 

[sparks1234]

i think he means 4+4+2.5=10.5

I thought 4mm t an e had a 1=5 earth

 

[Des 56]

The 2.5 mm ring complies with the minimum 10 mm that they state
It is for all conductors including the live conductor 543.7.1.3
543.7.2.1 is just saying that a ring circuit can be used

The totoal of a standard 2.5 ring is 4x 2.5 and 2 x 1.5 = 13 mm

 

[bramboy]

Guidance note 5: Protection Against Electric Shock
(circuits with protective current exceeding 10mA)

Page 12 of the above figure 12.3 shows ring final circuit with 1.5 mm protective conductor.
figure 12.4 shows radial version with a 1.5 mm protective conductor wired as a ring, keeping duplicate protective conductor close to circuit conductors to reduce emc effects.