Although technically its R1+R2 for your radial circuits. Whereas you record r1+r2 around your RFC with the highest value being classed as R1+R2. Is this a play on the capital 'R' telectrix?
 
Although technically its R1+R2 for your radial circuits. Whereas you record r1+r2 around your RFC with the highest value being classed as R1+R2. Is this a play on the capital 'R' telectrix?

Don't forget your divide by 4 now! :-)
 
Quick quiz for you

A RFC has continuity values of r1=0.4 ohms, rn=0.4 ohms and r2=0.4 ohms

What is r1+r2?
What is R1+R2?
 
Although technically its R1+R2 for your radial circuits. Whereas you record r1+r2 around your RFC with the highest value being classed as R1+R2. Is this a play on the capital 'R' telectrix?

no. with a rfc, you measure end/end of each conductor. these values are denoted by lower case r. when you cross connect on a RFC, or just connect L-E on a radial, you then measure R1+R2. ( denoted by upper case R ).
 
Quick quiz for you

A RFC has continuity values of r1=0.4 ohms, rn=0.4 ohms and r2=0.4 ohms

What is r1+r2?
What is R1+R2?

Ok. Here it goes. I would take r1 (0.4) and r2 (0.4) add them together (0.8) and then divide by 4 (=0.2). This would be the reading I would expect for all outlets within the ring main. So I test and I test, and test some more jotting down all my values as r1+r2. As I test, I notice I have what I think is a spur as the value is greatest and is actually 0.36ohms. This value being the greatest of the circuit is recorded as my R1+R2 for the ring circuit. PS: with the values you gave, I'm guessing the cables used are singles. Did I Pass?
 
no. with a rfc, you measure end/end of each conductor. these values are denoted by lower case r. when you cross connect on a RFC, or just connect L-E on a radial, you then measure R1+R2. ( denoted by upper case R ).

I get it now haha :willy_nilly:
 
it also stands for Rugby Football Club, but i wouldn't like to attempt an IR test on a prop forward.
 
Ok. Here it goes. I would take r1 (0.4) and r2 (0.4) add them together (0.8) and then divide by 4 (=0.2). This would be the reading I would expect for all outlets within the ring main. So I test and I test, and test some more jotting down all my values as r1+r2. As I test, I notice I have what I think is a spur as the value is greatest and is actually 0.36ohms. This value being the greatest of the circuit is recorded as my R1+R2 for the ring circuit. PS: with the values you gave, I'm guessing the cables used are singles. Did I Pass?

yes, but cable could also be SWA with the armour earthed but not used as cpc. the cpc core is the same size as the L and N.
 
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0.00 ohms r1+r2 on radial circuit?
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Periodic Inspection Reporting & Certification
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