Varying continuity readings

[pig]

Hi all,
I am using a Fluke 1662 with fused test leads. I find when doing continuity tests such as R1+R2, as the test button is being held the result fluctuates dramatically. Both increasing and decreasing. Seems to happen on insulation resistance as well however not so much. I also find after zeroing the leads with the Fluke zeroing adaptor, I press the test button again with the leads still in the adaptor and get a reading between 0.20 and 0.80 ohms.
Used a Megger before and never came across this.

Regards.

 

[buzzlightyear]

Bad allergator clips ?or leads
Ring up fluke and ask the Tec dept .

 

[pig]

Bad allergator clips ?or leads
Ring up fluke and ask the Tec dept .

I did sway towards this as I don't seem to get it when using the plug top test lead. Just wondering if anyone had experienced something similar before

 

[buzzlightyear]

Not me always used a megger .have cut my teeth on them .what do the manual tell you for problems.

 

[pig]

Not me always used a megger .have cut my teeth on them .what do the manual tell you for problems.

Not a lot really. Says how to zero the leads etc but that's about it

 

[Midwest]

I had similar with a megger, even with replacment leads. Was a dodgy terminal, which required repair.

 

[suffolkspark]

If it doesnt do it with your plug in lead... Then its your leads lol, if you want a good set of leads and croc clips at the moment theres some new RS phase rotation meters on ebay for about £21.99 delivered

Item no. 223214624444

Its unlikely youll get a set of leads and crocs at that price alone

 

[Octopus]

When my Metrel does this, its time to buy new leads .........

 

[Pete999]

Bad allergator clips ?or leads
Ring up fluke and ask the Tec dept .

You mean Crocerdile clips don't you Buzz? sorry Mate just messing with your head no malice intended

 

[ChrisElectrical88]

Leads or clips or even batterys. I go through 3 or 4 pair of leads a year.

 

[Jim_e_Jib]

I did sway towards this as I don't seem to get it when using the plug top test lead. Just wondering if anyone had experienced something similar before

I remember reading somewhere, possibly on this forum, that the Fluke fused probes can be a bit temperamental. If you're dead testing, you could try the non fused probes and see if the results are any different. If they are, perhaps the fuses and contacts need a bit of a clean.

 

[PEG]

Any capacitance on the installations you are testing?
Are the symptoms identical,when leads are reversed?

 

[The Ghost]

I have had this problem but with an old meter. If I left it in the vehicle overnight it would be very variable on low ohms readings. Keep it in the warm and dry no problem. Obviously condensation problems in my case.

 

[Andy5678]

I think I may have the same sort of issue as vort. If I blow into the connections of the leads and the MFT the resistance of the leads drops from around 0.30 to 0.10 and I get much more accurate readings. Moving about the cable at the ports also helps too. I also change leads regulary and have the same problems each time . Calibration is also done every year.

 

[static zap]

.... If I blow into the connections of the leads and the MFT the resistance of the leads drops from around 0.30 to 0.10 ....

Different metals ,and slight temperature differences -that will disappear with time when plugged in . Can make any DC measurements drift ... milivolts !
(Not sure if MFT is using AC ?)