fluke 1652c continuity readings

[Lilyrose08]

Hi all I keep having problems with my fluke the continuity readings are all over the shop never stable I always check my readings on a calcard before testing and when nulled I get correct reading i will test it on calcard 5 minutes later and it's half an ohm out so never know if I am getting an accurate reading test leads are not that old and battery's are still Fine has anyone else had problems with fluke continuity readings

 

[flowlec1]

I've had problems but it's usually the leads. The rep did say to turn it on and wait before you put the leads in.

 

[HandySparks]

Yes sometimes.

If you have alternative leads, it's worth seeing if that makes a difference. Even new leads can be damaged if pulled. Also the lead sockets on the MFT can be damaged if your leads are caught up and you try to move the tester away.

I also think that cold and damp can affect a MFT. Don't keep it in the van overnight during the winter.

 

[yellowvanman]

My experience is that the leads aren't much good, have been for years. At the moment I've got a set of Megger leads that I use - bit more consistent

 

[LectriCare Ian]

I've had problems but it's usually the leads. The rep did say to turn it on and wait before you put the leads in.

He's suggesting this because the tester only performs a 'cut down' version of its power-on-self-test if leads are detected in either the Red L (V Ohms) or Green PE (COM) socket. The Blue N (N) socket does not have 'input jack detection' (as Fluke call it) but all three sockets are of the split type, the metal part of the socket is in two C-shaped halves as viewed from above, this means that the socket is slightly weaker than you might expect, plus the soldering of the sockets to the circuit board is often skimpy at best.

 

[Geoffsd]

I once had trouble with mine.

The fuse holder jaws were very loose.

 

[thekingiam]

hmm i have had same problem with my metrel lately might have a look at fuse connections its fine when nulled and can constantly get zero afterwards but when testing get vairying results under an ohm

 

[LectriCare Ian]

We're going off topic here a little, but I've seen a Metrel EasiTest give incorrect readings on continuity due to a very unusual problem. The problem was that the switch for the 'Start' button had become high in resistance - it is the most used switch after all. Each switch has a different value of resistor in series with it, the microcontroller 'knows' which button you've pressed because it receives a different voltage. The varying resistance of the Start switch caused it to occasionally 'mimic' the 'Cal' switch (Metrel's term for continuity zeroing). Since this was happening with the leads connected to the installation circuits being tested, rather than being shorted together, when the tester did produce a reading it was lower than expected and not consistent due to 'phantom re-zeroing' happening occasionally. A new Start switch cured the problem.

Thinking again about the OP's problem, this is a Fluke 1652C and therefore should have the latest type of test leads with thick black rubber insulation. These are much better quality than the coloured leads supplied with early testers. If the probes are removed, just one lead at a time can be connected to the tester's L (V Ohms) and PE (COM) terminals, forming a loop. Thus the leads can be checked individually for high resistance/breaks/zeroing issues. It is unlikely that all 3 would be faulty so if none seem to be stable this would suggest a problem with the tester itself. A poor connection on the fuseholder in the battery compartment could produce similar problems.