earth leakage

[Charlie_]

a friend of mine told me he uses the clamp meter for his ir tests dosent do any ir testing just calculates the ir from the leakage current he detects whats your thoughts on that says it saves him lots of time still need convincing that this is ok

I use that method on jobs where I need to know the ir but can’t turn the power off

 

[static zap]

a friend of mine told me he uses the clamp meter for his ir tests dosent do any ir testing just calculates the ir from the leakage current he detects

Does sound dodgy ,if no one else can get same figure with 500V .
Can see where he is coming from Not having to unplug all those delicate electronics (they get tested at 380-400VDC)

 

[Farmelectrics]

its a good idea and would save you lots of time quick clamp and calculate and onto the next one or better still the pub quicker. would be good before a board change

 

[Charlie_]

Also you need to know that when using ac to test we will be measuring impedance and not resistance as in a dc IR text

 

[Pete999]

Computers, SMPS, TV boxes, play stations. etc

 

[Charlie_]

RCBOs with functional earths?

 

[static zap]

.......... ac to test we will be measuring impedance and not resistance as in a dc IR text

Wot I need power factor in my clamp meter ?

 

[Charlie_]

Wot I need power factor in my clamp meter ?

Not sure what you mean?

So if using an EL clamp to calculate IR you would be calculating the impedance as the insulation has a capacitive reactance..
We use dc voltage to measure just the resistance and the capacitive component is ignored.

 

[static zap]

So if using an EL clamp to calculate IR you would be calculating the impedance as the insulation has a capacitive reactance..

Insulation impedance (including capacitive reactance that could raise current ,but not power consumption... Hence appearing a little lower Z than actual R.
Was hoping for some amazing science ,(but with only the current -It cannot know the phase of the voltage to {filter-out} capacitive part of current )
Not to matter.

 

[cliffed]

My reckoning ,0.046 M ohms.