Discuss MEASUREMENT OF LEAKAGE CURRENT in the Periodic Inspection Reporting & Certification area at ElectriciansForums.net

Welcome to ElectriciansForums.net - The American Electrical Advice Forum
Head straight to the main forums to chat by click here:   American Electrical Advice Forum

Farmelectrics

-
Arms
Reaction score
520
I WAS ONCE SHOWN HOW TO CALCULATE INSULATION RESISTANCE USING A CLAMP METER. SO I NEED HELP AS IVE FORGOTTEN. CAN ANYONE HELP WITH THIS FOLLOWING FORMULA 230 + (20X10-6) = 11.5Mohms how have the arrived at this. A clamp meter has been clamped around live and neutral tails at the consumer and 2mili amps leakage 0.02mA is apparently 20micro joules. HELP
 
I WAS ONCE SHOWN HOW TO CALCULATE INSULATION RESISTANCE USING A CLAMP METER. SO I NEED HELP AS IVE FORGOTTEN. CAN ANYONE HELP WITH THIS FOLLOWING FORMULA 230 + (20X10-6) = 11.5Mohms how have the arrived at this. A clamp meter has been clamped around live and neutral tails at the consumer and 2mili amps leakage 0.02mA is apparently 20micro joules. HELP

I WAS ONCE SHOWN HOW TO CALCULATE INSULATION RESISTANCE USING A CLAMP METER. SO I NEED HELP AS IVE FORGOTTEN. CAN ANYONE HELP WITH THIS FOLLOWING FORMULA 230 + (20X10-6) = 11.5Mohms how have the arrived at this. A clamp meter has been clamped around live and neutral tails at the consumer and 2mili amps leakage 0.02mA is apparently 20micro joules. HELP
 

Attachments

  • INSULATION RESISTANCE WITH A CLAMP METER.pdf
    1.5 MB · Views: 12
You've copied the (admittedly fuzzy) formula from the document wrongly. It's division, not '+'
Resistance = voltage divided by current!
and of course 20 times 10 to the power of -6 for micro amps 🙂
0.02mA is 20 microamps! Not 2 milliamps
And keep away from Joules - you want ohms law and resistance, not energy!

PS you would normally want to measure insulation resistance at increased voltage, eg 500v or 1kV if in doubt about condition of the wiring, so the clamp meter method is not ideal!

sum is 230/(20x10^-6) ohms
Same as 230/20 x 10^6
= 11.5 x 10^6 ohms
= 11.5 Megohms (or Megaohms if you prefer!)
 
Last edited:
You've copied the (admittedly fuzzy) formula from the document wrongly. It's division, not '+'
Resistance = voltage divided by current!
and of course 20 times 10 to the power of -6 for micro amps 🙂
0.02mA is 20 microamps! Not 2 milliamps
And keep away from Joules - you want ohms law and resistance, not energy!

PS you would normally want to measure insulation resistance at increased voltage, eg 500v or 1kV if in doubt about condition of the wiring, so the clamp meter method is not ideal!

sum is 230/(20x10^-6) ohms
Same as 230/20 x 10^6
= 11.5 x 10^6 ohms
= 11.5 Megohms (or Megaohms if you prefer!)
THANKS FOR YOUR HELP AVO
 

Reply to MEASUREMENT OF LEAKAGE CURRENT in the Periodic Inspection Reporting & Certification area at ElectriciansForums.net

OFFICIAL SPONSORS

Electrical Goods - Electrical Tools - Brand Names Electrician Courses Green Electrical Goods PCB Way Electrical Goods - Electrical Tools - Brand Names Pushfit Wire Connectors Electric Underfloor Heating Electrician Courses
These Official Forum Sponsors May Provide Discounts to Regular Forum Members - If you would like to sponsor us then CLICK HERE and post a thread with who you are, and we'll send you some stats etc
This website was designed, optimised and is hosted by Untold Media. Operating under the name Untold Media since 2001.
Back
Top
AdBlock Detected

We get it, advertisements are annoying!

Sure, ad-blocking software does a great job at blocking ads, but it also blocks useful features of our website. For the best site experience please disable your AdBlocker.

I've Disabled AdBlock