Max demand Help needed please

[Dannywhite]

Hi I have an assignment to complete and it's asking for max demand before diversity and max demand with diversity, I'm basically stuck on how to work it out.

Any help is appreciated I have about 30-35 circuits

 

[Leesparkykent]

Hi Danny, do you have a copy of the on site guide?

 

[Dannywhite]

Yes mate what page?

Hi Danny, do you have a copy of the on site guide?

 

[Leesparkykent]

Yes mate what page?

I don't have the OSG around me but iirc appendix 1 around page 97ish....could be wrong though.

 

[Leesparkykent]

Just found this. http://www.napitonline.com/downloads/CP 4 07 P 10-11 16th Diversity.pdf

 

[Dannywhite]

Just found this. http://www.napitonline.com/downloads/CP 4 07 P 10-11 16th Diversity.pdf

Yeah that helps, how do I work it out before diversity though as it only applies diversity ?

 

[Leesparkykent]

Yeah that helps, how do I work it out before diversity though as it only applies diversity ?

what circuits do you have and what equipment is on the circuit? The question/scenario must give you some info to base calculations on? Could you scan/take a picture and post it up?

 

[Dannywhite]

I have a table of circuits with full Ib , Iz etc on it I will post it up shortly

 

[Dannywhite]

what circuits do you have and what equipment is on the circuit? The question/scenario must give you some info to base calculations on? Could you scan/take a picture and post it up?

 

[Dannywhite]

Anyone help please all the circuits are above, don't know how many in total but need the max demand before diversity and max demand after diversity !

 

[davesparks]

Ok, so first off do you understand what you are being asked to do and what terminology means?

 

[Dannywhite]

Ok, so first off do you understand what you are being asked to do and what terminology means?

Yeah I've been asked to work out the voltage drop, the Ib, Iz etc, after doing endless drawings Worked out the cable sizes and literally just stuck on max demand, I know before diversity is applied it's just the Ib added all together or the In (can't remember exactly but I'll put both figures in) and I'm stuck on the diversity bit thanks

 

[Ian1981]

Yeah I've been asked to work out the voltage drop, the Ib, Iz etc, after doing endless drawings Worked out the cable sizes and literally just stuck on max demand, I know before diversity is applied it's just the Ib added all together or the In (can't remember exactly but I'll put both figures in) and I'm stuck on the diversity bit thanks

Ib is your design current and In is your protective device.
Guidance note 1 and on site guide you need for working out diversity.

 

[telectrix]

Ib is your design current and In is your protective device.
Guidance note 1 and on site guide you need for working out diversity.

or just guess better than osg. their figures are at best a guess and at worst a value pulled out of a hat.

 

[Ian1981]

or just guess better than osg. their figures are at best a guess and at worst a value pulled out of a hat.

Agreed why they still bang on about 100w lamps max for domestic lighting, hopefully the new 18th will compensate for the lack of.