IET logo
 
IET
Decrease font size
Increase font size
Topic Title: circuit design
Topic Summary:
Created On: 05 March 2013 09:01 AM
Status: Post and Reply
Linear : Threading : Single : Branch
Search Topic Search Topic
Topic Tools Topic Tools
View similar topics View similar topics
View topic in raw text format. Print this topic.
 05 March 2013 09:01 AM
User is offline View Users Profile Print this message



newelectrician

Posts: 13
Joined: 05 July 2011

following was posted in another forum:

I can answer why Dom installers are hated so much in one question get it right and ill be very shocked. 3k heater wired in 2.5/1.5 over a 18 meter run bunched in trunking with a ze of 0.18 ohms 230v . Is this cpc ok? And give me the minimum cpc size you could use using calculations.
___________________________________________________

im still learning and tried to do the above calc, but dont i need to know how many cables/circuits are bunched in the trunking to get the correct answer (Cg). please help and advise or correct me thanks
 05 March 2013 09:11 AM
User is offline View Users Profile Print this message



AJJewsbury

Posts: 11379
Joined: 13 August 2003

It's only asking about the adequacy of the c.p.c. size, not the live conductors size, so you don't really need Cg to answer that bit.

You should be able to work out R1 and R2 from the cable length & c.s.a.s.

Even so, I'm not sure how it can be answered without knowing the characteristics of the protective device...

I presume the OP means a 3kW heater, rather than a 3 kelvin one, and there aren't any submains.

- Andy.
 05 March 2013 09:57 AM
User is offline View Users Profile Print this message



newelectrician

Posts: 13
Joined: 05 July 2011

thanks, i was just trying to test myself to see if i fully understood all the calcs involved, i thought something was missing from question
Statistics

See Also:



FuseTalk Standard Edition v3.2 - © 1999-2014 FuseTalk Inc. All rights reserved.