hi have a r1 r2 mystery

[ianphilip007]

hi have been doing some testing on a existing light circuit usual methos line /cpc linked at board leads and link lead nulled. come accross a very strange problem regurding a R1 R2 reading

Now measuring between sw live and cpc. rose 1/ 0.47 rose 2/1.15 (2WAY SWITCHING) 3 rose 3/0.51 rose 4/ 0.54 rose 5/1.07 rose6/1.97 (2 WAY SWITCHING)

all connections at rose 2 have been checked, switch connections on 2way switching checked, resistance of the actual switches has been measured and switches replaced as i just just thought it was a bad connection giving a false reading,or a high resistance switch but im still getting a high reading which is impossible as the R1 R2 reading at the next rose in the line is only 0.51. Its very strange as the measurment from loop in at the rose to CPC is fine and is as expectected which scuppered my other theory that this rose had been wired out of sequence.

any ideas any one. Just to add when ZS tested readings as expected which again just makes iot stranger.

 

[spark 68]

yes totallly agree spark that the longer the switch run the higher the reading but wouldnt the previous switch run resistance still show if all the switches are in closed postion at the next rose or am i missing something simple here its been along day

I think you are confusing your switch lives with your permanent lives.

The switch cable may be quite abit longer (bearing in mind the S/L has twice the distance of the run) than the next roses P/L which is only one length of the run (no return).

Each rose normally has it's own S/L unless both roses are switched from the same switch.

 

[spark 68]

Ian,
your S/L's are all only connected to the P/L via the switch cable at one side of each switch, you are effectively measuring your R1 at the other side of each switch at each rose, these are seperated from each other, or else all of your lights would come on together

 

[ianphilip007]

thanks alot guys for all your help much appreciated

 

[PC Electrics]

Draw it out on a piece of paper and it will become obvious to you what is being said above.

thanks alot guys for all your help much appreciated

Does this mean you're fed up thinking about it, or is the "light" on now?

 

[Strima]

or is the "light" on now?

Or is the 'lamp illuminated' a better phrase to use? :lol:

 

[ianphilip007]

yes thanks guys the light has come on as has been said when you draw it out its obvious thanks again

 

[Moses]

thats a thought one thing i didnt measure maybe its pendant giving a high reading at that point, what is baffling me is the next pendant is showing a lower reading surely this pendant would also be giving a high reading

there could be a connector/ J/B on the switched wire, with loose connections giving rise to Hi R1+R2