anyone recommend an earth leakage clamp meter ?

[petehall347]

How well does this meter do on DC current measurements I know how well Flukes do on AC current measurements but have no experience with them with dc clamp meters and if you want for DC current measurements is worth the extra money compared to the Fluke 902FC

Because I am looking at this one but I want to know is worth the difference between the one I have and the capability of this one
Fluke 376 FC True-RMS AC/DC Clamp Meter

https://www.ebay.com/itm/32609859833...Bk9SR8yryP_iYw

The difference between these two clamp on meters is about double the price

from what i have read there aren't any dc clamp meters that are accurate at low currents ,

[CapLeaker]

How well does this meter do on DC current measurements I know how well Flukes do on AC current measurements but have no experience with them with dc clamp meters and if you want for DC current measurements is worth the extra money compared to the Fluke 902FC

Because I am looking at this one but I want to know is worth the difference between the one I have and the capability of this one
Fluke 376 FC True-RMS AC/DC Clamp Meter

https://www.ebay.com/itm/32609859833...Bk9SR8yryP_iYw

The difference between these two clamp on meters is about double the price

What are you looking for to do with it? What are your minimum requirements?

[sam_sam_sam]

Fluke 393FC works every time.

How well does this meter do on DC current measurements I know how well Flukes do on AC current measurements but have no experience with them with dc clamp meters and if you want for DC current measurements is worth the extra money compared to the Fluke 902FC

Because I am looking at this one but I want to know is worth the difference between the one I have and the capability of this one
Fluke 376 FC True-RMS AC/DC Clamp Meter

https://www.ebay.com/itm/32609859833...Bk9SR8yryP_iYw

The difference between these two clamp on meters is about double the price

[petehall347]

been working out what system this is here .. best i can work out is TNCS with added ground rod . earth wire connects to incoming neutral and also to a ground rod .. i was always told its TT but it can't be .

[CapLeaker]

yes i have seen water pipe like that here . earth bonding to them too .

Well… that's creating grounding issues, A ground on a plastic pipe is worth zero. My CATV cable is grounded to the power entrance ground before it goes to the modem. Proper earth ground is your friend, Keep in mind your soil or rocks / ledge etc. As ground conductivity gets worse, you need more ground plates,

[redwire]

Also consider the natural gas and sewage pipes, if they are metal outside the house. You can get some weird paths for ground currents by appliances that cross-connect. CATV as well.
Here a (hot galvanized zinc) ground-plate I have seen embedded inside concrete foundation walls.
I've used copper ground rods but sometimes you can put one in and it's high impedance and you have to move to another spot. Depends on the soil and rock. Frequently the wire connection to the ground rod corrodes and goes bad with age.

I thought it's been really wet over there?

[petehall347]

Yeah, thanks but no thanks. Install proper grounding. Better than ground rods are ground plates. Not all water pipe is made out of metal either. I know places where all inside is metal piping. However the feed from the main water line on the street to the house is PVC. Do it right.

yes i have seen water pipe like that here . earth bonding to them too .

[CapLeaker]

Yeah, thanks but no thanks. Install proper grounding. Better than ground rods are ground plates. Not all water pipe is made out of metal either. I know places where all inside is metal piping. However the feed from the main water line on the street to the house is PVC. Do it right.

[stj]

LOL - that water pipe!
i went to a flat once that could zap you from the taps!!!
inductive coupling because the water company had replaced the old pipe with a poly one!!
i had to go into the basement and reconfigure the earthing from the water line to the incomming power shielding.
got some great sparks when i connected it!

[petehall347]

cant edit last post but that diagram is not exact same as here it has ground rod at entry point

[petehall347]

ah i see whats been done now . its combined tns and tt which shouldn't be done . however it did provide grounding to the main system when the incoming ground neutral became detached from the ground . thinking best way of doing the mobile homes is having their own ground rods independent of the main supply by disconnecting the supply ground wires at the mobile homes supply and just using ground rods . TT .
this is how it stands but water pipe is ground rod . there is no metal water pipes on site .

[CapLeaker]

Oyyy! This story is getting better by each post! The ground rods supposed to be connected together via a ground cable, not through the power cables! Maybe explain why each unit has a separate ground rod, while the main power entrance has one?
I've got multiple ground plates in 3 different locations around my house that are all joined together. Why? I didn't like the zapping during lightning storms. Since I did that 20 years ago, no more zapping going on inside my radios.
Extra ground rods that aren't connected through an extra large diameter ground cable to them selves is a no no!
If you measure at each ground rod, chances are good, every rod has different readings. That shouldn't be.

[petehall347]

Aren't all these ground rods connected directly together?

yes they connect together through the power cables .

[CapLeaker]

Aren't all these ground rods connected directly together?

[petehall347]

how do rats chew the cables? isnt it concentric?

they chew anything except anything coated in waste engine oil .

[redwire]

When the main earth rod went open, if there ever was a (distribution system) ground fault, high current would get pulled from your local ground plus any appliance with metal piping.
It's possible that overload made a ground wire/connection go open circuit. Look for an open ground resulting from the main ground failing.

[stj]

how do rats chew the cables? isnt it concentric?

[petehall347]

found something now and made it better . turned out the main earth rod that connects the supply neutral had corroded away so we no longer had that earth until i knocked it into the ground and watered it . now its just showing combined leakage of about 50 to 60ma . and the 2 other ground rods about 5ma as expected .
so its as i expected my supply and the other with ground rod was providing the earth .
plus i found the main cables were chewed by rats exposing the bare wires so coated them with conformal coating which lowered the leakage somewhat .
still not figured why the 30ma rcd is staying on with 30ma leakage . only cure i reckon is fit a 100ma rcd then it will be sorted .

[petehall347]

latest findings today up till now . there are 2 of us that run off the supply from the rcd in question and we are about 120 metres maybe more from the supply .there is about 5ma leakage each measured across live neutral so that's good . now where it gets interesting is we both have local ground rods and both are carrying around 30ma each after isolating our consumer units so its looking like the problem is closer to source .our neutral to grounds measure about 1.2v so can call that good .

[CapLeaker]

petehall347 while your at it, post some pics. Man, I am getting curious on where this comes from.