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TheCodboy

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Hi all, Doing some pre board change testing and ive found 2 sockets with high Zs readings. Everything else is fine, done all my end to ends and the Zs's are what should be expected. A couple of the sockets have Zs lower than expected but 2 are higher. They should be about 0.8 ohms but ive got one at 1.20 and one at 1.40. Taken the highest value socket off, re terminated, still high. Tested at the terminals of the socket just in case the socket was duff, but still high. Its a PME system with a good low ZE (0.15). Any thoughts people??
 
Hi all, Doing some pre board change testing and ive found 2 sockets with high Zs readings. Everything else is fine, done all my end to ends and the Zs's are what should be expected. A couple of the sockets have Zs lower than expected but 2 are higher. They should be about 0.8 ohms but ive got one at 1.20 and one at 1.40. Taken the highest value socket off, re terminated, still high. Tested at the terminals of the socket just in case the socket was duff, but still high. Its a PME system with a good low ZE (0.15). Any thoughts people??
Are the sockets in question spurs?
 
Did you test between line and neutral as well. Have you confirmed they are not spurred.
 
The property is a bungalow with the cable drops coming in from the loft. The socket with the highest value has the ring coming in from above, and the cable looks to be original.
 
I had a job this week, where I removed some diy work on what I thought was an RFC in an existing extension. Well I thought it was an RFC, but in fact it was fed via a spur from another RFC.
 
how many cables was at this socket ? you posted you had done end to end at consumer unit (assumed) what about r1 + r2
The socket with the highest reading had 2 x 2.5 T&E. Took L-L, N-N, E-E reading at the consumer unit. r1 + r2/4 + Ze = 0.82 Ze was measured at 0.14. The calculated Zs of 0.82 was very near what i was getting all around the ring. 2 sockets were a bit lower (0.45 & 0.55) and apart from the 2 that were high, the rest were virtually spot on. ( My end to end values were L=0.92 N=0.92 E=1.83)
 

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