clamp meeter on ring

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i found a bit of a fryed cable on a job that the company i work for did a while ago. it was a 2.5 ring main supplying a comertial kitchen.
the ring was not over loaded and the burning was only on one cable.
i put a clamp meeter on the ring,
one leg was 10.4 A
the other was 0.6 A

shouldn't they be the same if it was a ring?

there was continuity between the 2 legs of the ring and no lose connections, all sockets were checked

any one had something like this happen to them before?

 

[RF Lighting]

The load will only be the same on both legs if the appliance is plugged in exactly at the mid point of the ring.

Electricity is lazy, and will take the path of least resistance (The shortest leg to the socket supplying the appliance)

 

[GaryMo]

Hence its very important to think about appliances that will be used on a ringmain and how you wire it.

 

[bernardgreen]

one leg was 10.4 A
the other was 0.6 A

shouldn't they be the same if it was a ring?

The ratio of the currents to a single load on a ring would be the inverse of the ratio of the resistances in the legs to the load. Assuming all wired in 2.5mm² the resistances per leg are proportional to length of leg.

ratio 10.4 to 0.6 is 17 so the one leg from CU to load was 17 times the length of the other leg if there were no high resistive joints


<<edit>> ratios 10.4 to 0.6 is 30 corrected (nayone got a decent calculator)

there was continuity between the 2 legs of the ring and no lose connections, all sockets were checked

Out of interest what were the resistances measured during the continuity testing.

 

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i cant rember it was a fue weeks ago i did put it down on paper but that could be any where by now

its just been puzzling me for a while