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I have been using the 760-1 for about a year now and can't fault it in any way, the problem being if it ever goes missing and I go back to a multi position dial meter I am sure I will rely on the auto setting and blow it to smithereens.

If you have your 760-1 to hand, and some T&E cable lying around, can you have a go at L-E capacitance measurement, etc, just to see if it gives any usable results here?
 
I have the 760-1 to hand, but no T&E.

Maybe try with an IEC lead or similar?

A 2m "clover leaf" style cable here for a laptop supply measures around 180pF conductor to conductor on my capacitance meter, just be interesting to see if your multimeter can show that at all.
 
I also often use capacitance to roughly locate an open in a cable that has quirks and interconnections that will give confusing results on a TDR plot. Simply identifying which end of a cable has an open pin on a moulded connector is often all that is required, in which case the bad end will have near zero stray capacitance and the actual reading at the other end doesn't matter. In reality I probably use my capacitance meter more for that kind of thing than measuring capacitors. Capacitance measurement works well on T+E, but the results will vary according to how the CPC is connected and to a lesser extent how it is bundled or in contact with earthed stuff. Probably best to measure between one or both live cores and the CPC.

I had to create a Heath-Robinson TDR setup in the middle of nowhere, when I had access to a computer and a monitor but no test gear. A TDR set sends out pulses and times the delay before reflections are received that indicate open- and short-circuits by their abrupt changes in characteristic impedance. I used the computer and monitor to do the same thing. I stripped a section in the middle of the monitor's RGB cable, broke into the green channel and paralleled a pair of very short test leads. By displaying a clear vertical bar on the computer and measuring the distance on-screen between the true image and the ghost with the test leads connected to each end in turn, I could calculate what fraction of the length lay between each end and the fault (It was exactly 100m if my memory is correct. The cable was defective in manufacture and there was a feeding-in splice in the core that should never have been present in the finished product)
 
I also often use capacitance to roughly locate an open in a cable that has quirks and interconnections that will give confusing results on a TDR plot. Simply identifying which end of a cable has an open pin on a moulded connector is often all that is required, in which case the bad end will have near zero stray capacitance and the actual reading at the other end doesn't matter. In reality I probably use my capacitance meter more for that kind of thing than measuring capacitors. Capacitance measurement works well on T+E, but the results will vary according to how the CPC is connected and to a lesser extent how it is bundled or in contact with earthed stuff. Probably best to measure between one or both live cores and the CPC.

I had to create a Heath-Robinson TDR setup in the middle of nowhere, when I had access to a computer and a monitor but no test gear. A TDR set sends out pulses and times the delay before reflections are received that indicate open- and short-circuits by their abrupt changes in characteristic impedance. I used the computer and monitor to do the same thing. I stripped a section in the middle of the monitor's RGB cable, broke into the green channel and paralleled a pair of very short test leads. By displaying a clear vertical bar on the computer and measuring the distance on-screen between the true image and the ghost with the test leads connected to each end in turn, I could calculate what fraction of the length lay between each end and the fault (It was exactly 100m if my memory is correct. The cable was defective in manufacture and there was a feeding-in splice in the core that should never have been present in the finished product)

That's bloody creative is that.
 
That is a very inventive solution to not having TDR equipment to hand, shame it is no longer possible in the HDMI era!

Sometimes you get really odd results and then discover that you actually have a really odd setup. In one case I guy I worked with was deeply puzzled by some results and then pulled up the false floor panel to discover that yes, there really was 100m of cable between two racks barely 1m apart!
 
Tried various cables and permutations with no useful results, I don't think the 760-1 is sensitive/sophisticated enough, but an interesting exercise just the same.

Well that is at least useful to know, so unless someone has the '2' version of that meter or better it might not be usable.

I realised the cable I checked earlier was actually Doncaster 1.5mm T&E, found the Prysmian 2.5mm off-cut and it is 141pF/m for phase-earth, and 243pF/m for L+N -> E
 
I have spent quite a bit of my life troubleshooting under pressure, sometimes in adverse conditions. You get creative or get fired.
 
had somewhat similar recently. there was a 20A D/P switch in the kitchen. customer used to leave the FCU in the airing cupboard permanently on and use the kitchen switch. the fault was O/C pole in this switch.
Had exactly the same, one FCU in the airing cupboard and one in the under stairs cupboard.

The tenant pointed it out to me as I was busy pulling my hair out.
 
I've even found the original butchered cable, but it turns out the monitor I was going to use doesn't have a VGA input as I had thought, so I'll have to do it tomorrow.
 
had somewhat similar recently. there was a 20A D/P switch in the kitchen. customer used to leave the FCU in the airing cupboard permanently on and use the kitchen switch. the fault was O/C pole in this switch.
Had that before as well. However is want an open contact in switch. The tenants just hadn't turned the switch in the kitchen on as they didn't know what it was.
 

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