Multi-function Tester Question/Advice

[Jim2287]

This should probably be in another place on forum, but wanted response from electricians... sorry

At work we have a Megger/AVO CM500 , which is pretty good tester in my opinion. It tests earth loop with just two probes (no neutral needed) ...only prob is we need another tester and the CM500 is quite bulky

was looking at
Megger MFT1500 Series but these have three probes (neutral included) for earth loop and other live tests.

Do you need to use all three probes for an accurate reading on earth loop?
Do you need to use all three probes for the tester not to trip RCDs ? It says that it only use 15mA current to do earth loop, so shouldnt trip 30mA whether you use neutral probe or not?

Anyone with these testers could give some advice? ... or anyone could advise on other Multi-function testers ?(dont like the idea of seperates)


thanks

 

[Jim2287]

no ?

 

[Cremeegg]

OK I'll put you out of your misery.

Megger MFT1552 (an excellent bit of British made kit) will do a non-tripping loop test with three leads or use Meggers own 13A style test lead. It'll do a high current loop test using two leads.

1552 now updated as 1553 that'll download your results via Bluetooth - but you pay for the technology and is probably only worth it if you do alot of testing and already have the PDA. Old luddite that I am I haven't - yet.

No doubt this will bring forth the usual debate on my Fluke can do this; my Alphatek can do that ........

 

[ricicle]

And my Metrel can do the other.................

 

[Cremeegg]

I knew it wouldn't take long

 

[ricicle]

 

[Jim2287]

so you can not do a low current earth loop test with only two probes (live + earth) and not trip RCDs with the MFT1552 ?

 

[ebee]

The metrel (or the one I used a couple of times) is effectively a two lead EFLI tester because you can piggyback two clips together (IE join N & E to one probe/clip)

 

[Cremeegg]

Jim - correct - as my original post - for non tripping low current use three leads on the MFT1552; for tripping high current use two.

 

[Jim2287]

hmm pain in the bum leads are

 

[securespark]

Only if you sit on them...

 

[Jim2287]

doing IR

 

[securespark]

Did that the other day. Well, not my bum... My finger was touching a probe & I pushed the button in error. OW!!

 

[Jim2287]

ive only been done on capacitance so far , but that hurts enough

did do it to my mate by accident though and he shouted a little