Low PFC

[LeighCage]

A quick measurement using a EZ 2500 shows a PFC of 6A @ 40 Ohm. Given a 240V supply, the maths works out, but is this PFC on the low side? Not yet sure how the earth is provided, perhaps an earth rod. 40 Ohm just seems a little high to me. There is a 30mA RCD.

 

[Murdochcat]

What is your role in this ?

Odd question to say the least

 

[Risteard]

A quick measurement using a EZ 2500 shows a PFC of 6A @ 40 Ohm. Given a 240V supply, the maths works out, but is this PFC on the low side? Not yet sure how the earth is provided, perhaps an earth rod. 40 Ohm just seems a little high to me. There is a 30mA RCD.

You're mixing up PFC and PEFC.

 

[ericmark]

My first loop impedance tester auto measured line - neutral as current in amps, and line - earth as impedance in ohms, and also auto swapped which contacts it used on the kettle type connector.

However moving firms so Robin to Seaman, the new tested did not auto change the pins in the connector, and having been use to the Robin I did not check until I came to measure a TT installation.

I don't know the EZ 2500 but you do need to find out how your meter works, they are not all the same.

 

[ebee]

Yup, the old meters (analogue needle scale) measured the mains voltage and you manually adjusted it with a little knob (potentiometer) to zero refence it then pressed button and it placed a known load on it (say 10 ohms or something) for a few seconds and noted the difference in readings. this would give volt drop for a known load and you might hope your incoming voltage was fairly consistent between the two readings. The resistor (dummy load) would get hot and you only had to press for a few seconds or it could burn out and you had to leave it a while to cool down before repeating a test. Then some got some circuitry to do some stages automatically and often the meter would be digital.
That was later given by some a circuit to do things a bit differently because the currents involved were OK for fuses and breakers but not with a RCD in place, it would trip them.
Robin had a system called D-Lok which put some DC on the probes and that would saturate the iron core of a RCD to prevent it tripping - it often worked but not always.
Some suggested using linkwires to bypass the RCD and it was important to remove them once test was over or calamity could occur.
Some then used lower current to not trip an RCD but over a longer time period and in little samples to get a kind of "Average".
During this time the "meggers" lost the wind up hand crank to develop voltages and electronics did it.
Test gear was and is always evolving and we do not so much use bells, buzzers and lamps to test (was I know - some apparently still use the age od "Bang Bang 240v Test" and a mains tester screwdriver) .