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Products => Test Equipment => Topic started by: mpmansell on January 28, 2018, 05:08:33 pm

Title: Precision Gold N56FU (EM6000) Multimeter Failure on Ohms/Diod/Continuity/mV
Post by: mpmansell on January 28, 2018, 05:08:33 pm

Hi there.

I have a Precision Gold N56FU meter which I bought from Maplin in the UK about 10 years ago. It hasn't been so heavily used, but has been a decent meter for use with my home projects.

Just today I took it out to check some resistances and match a few transistors and discovered that it had failed on the Ohms/Diode/continuity and mV ranges. On mV it beeps constantly, although not entirely regularly and sometimes shows a reading, even though there is noting under test and the test probes open. If left long enough, it sometimes stops the beeping and shows -ve symbol and starts counting down from approx 600 (as I type it is -523.0 and still counting down).

On Ohms/Diode/Continuity, it shows none of the expected symbols with a reading of -0L and the 'C' from temperature measurement showing. presisng range does nothing (short, long and very long) and the only thing select does is toggle bweteen 'c' and 'f'.

As far as I can tell without any other equipment available currently, the other ranges appear functional (although I have no way of telling if the readings are barking mad, or good)

I have tried 2 fresh batteries and they, as well as the originally installed battery, read in excess of 9V.

I have opened the unit and checked/cleaned connections. There are no other apparent faults but I will look again, more closely when I have access to more test gear again.

Any ideas ?

Thanks

Title: Re: Precision Gold N56FU (EM6000) Multimeter Failure on Ohms/Diod/Continuity/mV
Post by: retiredcaps on January 28, 2018, 06:48:05 pm

Quote from: mpmansell on January 28, 2018, 05:08:33 pm

On Ohms/Diode/Continuity, it shows none of the expected symbols with a reading of -0L and the 'C' from temperature measurement showing. presisng range does nothing (short, long and very long) and the only thing select does is toggle bweteen 'c' and 'f'.

Look at the main IC datasheet for the above.  Many of these meters seems to follow the schematic in the datasheet.

Check the range switch/contacts for debris or oxidiation?

Title: Re: Precision Gold N56FU (EM6000) Multimeter Failure on Ohms/Diod/Continuity/mV
Post by: mpmansell on January 28, 2018, 11:40:39 pm

Thanks. I checked all those prior to posting but am a little limited until I can find another meter to race things through with. A visual inspection showed nothing obvious so will have to trace things a little more closely once I get hold of another meter