Multi meters and rcds

[cardiy]

Do basic CHEAP multi meters trip rcds when testing LN LE NE AT SOCKETS AND LIGHT SWITCHES?

 

[333rocky333]

Very unlikely, when testing L to N.

Unless a recent install , unlikely when testing at a light switch either, as the circuit most likely, NOT via an RCD.

 

[ColJack]

nope..
you're only checking for voltage that's a high enough resistance to limit the current.

it's the Zs that trips the RCD / RCBO's... unless you have one of those fancy meters.

 

[flameport]

No, the input impedance of the meter will be far to high to trip any RCD.

 

[cardiy]

Thanks guys

 

[RF Lighting]

No, the input impedance of the meter will be far to high to trip any RCD.

Unless you're using a fluke T-50

 

[Taylortwocities]

So you must have tripped it when doing something else then

 

[DCC]

That would be when grasping the probes and the cores to take a reading

 

[davelx]

They will trip on LE and probably NE if you set them to a current range by mistake

 

[CortinaV8]

No, the input impedance of the meter will be far to high to trip any RCD.

Unless you're using a fluke T-50

Damn right!

 

[Paul_C]

240V / 30mA = 8000 ohms. Even something like a 500 o.p.v. multi-meter would be well over that input resistance on what would have to be at least a 250V range. It's only going to trip if the meter deliberately introduces a low resistance across the terminals to apply a minimal load.

 

[CharlieL]

Are there still test meters that are as low as 500ohms per volt?

Can an electrician installing RCDs and CUs be trusted if he can't put his meter on the right range? Oh, yes, ee's got a stifficate, han ee!

 

[Taylortwocities]

Was there a reason for digging up a 6-month old topic, just for a cheap remark?

Or do you have something constuctive to add?