advantages and disadvantages

andy3050 · Posted: Wed Dec 08, 2004 1:30 pm Post Subject: advantages and disadvantages

what are the advantages and disadvantages of ring and radial circuits???

comms · Posted: Wed Dec 08, 2004 4:13 pm Post Subject:

Radial circuit; 4mm cable & a protective device of 30/32amp will serve a max floor area of 75m sq
Radial circuit; 2.5mm cable & a protective device of 20amp will serve a floor area of 50m sq

Ring main; 2.5mm cable & a protective device 0f 30/32amp will serve a floor area of 100m sq.

All the above can have unlimited outlets & fused spurs, you can have as many unfused spurs as there are outlets.

So basically it's down to area coverage & cost of 2.5mm cable against 4mm cable.

plugwash · Posted: Wed Dec 08, 2004 5:08 pm Post Subject:

the word spur has no real meaning in terms of a radial

its perfectly acceptable to take a branch off a radial to as many sockets as you like

pna · Posted: Thu Dec 09, 2004 11:54 am Post Subject:

Radials are easier to wire (ignoring 4mm over 2.5mm) as no need to get the cable back through to the CU to make a ring; the run length of cable for a radial circuits is also limited to circa 30m.