Non continuous beep on DMM in continuity mode - Fluke 117

StephenS147

On a CPC I'm getting a reading of 0.5 ohms in ohms mode and in continuity mode the meter is a continuous beep.

Then on another CPC I'm getting a reading of 0.7 ohms in ohms mode then in continuity mode the DMM is a non continuous beep.

The meter is a fluke 117. Any reason why the beep is not a continuous one? The manual doesn't have any info on this.

Lex Luthor

StephenS147 wrote: »

On a CPC I'm getting a reading of 0.5 ohms in ohms mode and in continuity mode the meter is a continuous beep.

Then on another CPC I'm getting a reading of 0.7 ohms in ohms mode then in continuity mode the DMM is a non continuous beep.

The meter is a fluke 117. Any reason why the beep is not a continuous one? The manual doesn't have any info on this.

just out of curiosity, whats a CPC?

StephenS147

Lex Luthor wrote: »

just out of curiosity, whats a CPC?

The earth. Circuit protective conductor.

Lex Luthor

is it to do with the settings of the meter that anything over 0.5ohms it does an intermittent beep rather than continous?

StephenS147

Lex Luthor wrote: »

is it to do with the settings of the meter that anything over 0.5ohms it does an intermittent beep rather than continous?

I've checked the manual and all it says is to use the ohms mode to get a more accurate reading.

I just find it strange that it's beeping like that.

There doesn't appear to be any setting that I can see to set the threshold.

Lex Luthor

StephenS147 wrote: »

I've checked the manual and all it says is to use the ohms mode to get a more accurate reading.

I just find it strange that it's beeping like that.

There doesn't appear to be any setting that I can see to set the threshold.

it might not be a setting but something thats configured in the software and not changeable

StephenS147

Lex Luthor wrote: »

it might not be a setting but something thats configured in the software and not changeable

Quite possible. At least there's good continuity anyway. So good to go regards that.

Lex Luthor

StephenS147 wrote: »

Quite possible. At least there's good continuity anyway. So good to go regards that.

ya 0.7ohms is a good figure

next time I have my fluke out I'll check and see if its similar

Cerco

Could the non-continuous tone be a voltage alert?

2011

StephenS147 wrote: »

On a CPC I'm getting a reading of 0.5 ohms in ohms mode and in continuity mode the meter is a continuous beep.

Then on another CPC I'm getting a reading of 0.7 ohms in ohms mode then in continuity mode the DMM is a non continuous beep.

The meter is a fluke 117. Any reason why the beep is not a continuous one? The manual doesn't have any info on this.

My guess is that 0. 7 ohms is above the threshold to be considered continuity and 0.5 ohms is below the threshold and therefore is recognized as achieving continuity.

StephenS147

I'm going to contact fluke support because it's intriguing why it's set to 0.5 ohms of that's the cause. I suppose higher end models have a setting for the threshold.

2011

StephenS147 wrote: »

I'm going to contact fluke support because it's intriguing why it's set to 0.5 ohms of that's the cause. I suppose higher end models have a setting for the threshold.

Insteco are the Fluke agent. I deal with them a lot. They are great to deal with.

Lenar3556

StephenS147 wrote: »

I'm going to contact fluke support because it's intriguing why it's set to 0.5 ohms of that's the cause. I suppose higher end models have a setting for the threshold.

I would be interested to hear their feedback. I don’t think it’s because the resistance is a little higher. I have seen that meter buzz continually and solid at 10+ ohms.
I wonder would it be caused by some AC on the circuit under test?

StephenS147

Lenar3556 wrote: »

I would be interested to hear their feedback. I don’t think it’s because the resistance is a little higher. I have seen that meter buzz continually and solid at 10+ ohms.
I wonder would it be caused by some AC on the circuit under test?

Could be possible. How do I measure that?

Lenar3556

StephenS147 wrote: »

Could be possible. How do I measure that?

I am guessing this was a loop and the CPC was disconnected on both ends when you took the measurement?

Was the circuit or other circuits in the vicinity powered up? It would be interesting to see did the intermittent beep stop if you switched off the main incoming supply.

To check for an AC (likely induced) voltage I would put the meter on AC volts and measure between one end of your CPC and a valid earth ( like earth bar on DB for example).

StephenS147

Lenar3556 wrote: »

I am guessing this was a loop and the CPC was disconnected on both ends when you took the measurement?

Was the circuit or other circuits in the vicinity powered up? It would be interesting to see did the intermittent beep stop if you switched off the main incoming supply.

To check for an AC (likely induced) voltage I would put the meter on AC volts and measure between one end of your CPC and a valid earth ( like earth bar on DB for example).

Thanks, not 100% certain if the power to the DB was all off. I know the circuits that were involved were turned off (obviously).

The earth was disconnected were I was testing.

What I was doing was checking the ohms between the first socket CPC to the section I'm branching off with a wago maintenance free box in the same room and then from the branched section to 6 outlets further down the same radial. I was doing this to ensure the CPC was continuous for the branched off part as I don't have test leads long enough to go to the CU.

This explains the slightly different reading of a 0.2ohms difference but doesn't explain the difference of beeps.

I'll have to get a long lead for testing this. I'll measure the resistance of the lead and subtract that when I take the reading.

Zarco

Isn't that a standard feature the beeping on very low ohms?.

On most DMMs ?

StephenS147

Zarco wrote: »

Isn't that a standard feature the beeping on very low ohms?.

On most DMMs ?

In my case 0.5ohms is continuous but on another separate reading of the CPC it's 0.7ohms with a beep every half a second or so.

Could be;
A feature (as already mentioned)
Low battery.
Higher impedance circuit (for beeper)
Meter auto-ranging / interference from induced electrical noise.

The tone of my 87V changes long before the low battery icon appears.
Sign of a good meter? Flick the probes super quick like a flint stick and it ought to beep. So handy for reverse engineering circuit boards, saves a lottov time.

StephenS147

Sir Liamalot wrote: »

Could be;
A feature (as already mentioned)
Low battery.
Higher impedance circuit (for beeper)
Meter auto-ranging / interference from induced electrical noise.

The tone of my 87V changes long before the low battery icon appears.
Sign of a good meter? Flick the probes super quick like a flint stick and it ought to beep. So handy for reverse engineering circuit boards, saves a lottov time.

I've only had a few hours out of a brand new 9v battery.

I've always flick the probes before testing continuity and that's fine.

I've tested the voltage of the two points I'm testing and it's reading 0.025 with the two ohms readings of 0.5 and 0.7 so there's no leaking current.

Fluke got back to me today and said: (I wrote the exact same email to them as per the starting post)

We cannot tell either, only give some small tips to check.
The 117 will beep continuously at any resistance lower as 20 ohm , see table 6 of the manual :
https://dam-assets.fluke.com/s3fs-public/110__117umeng0000.pdf?B7CA.PXFW6bSDk5D9HbVGUu8WPBGUjJu

The beeper will be quiet when resistance is 0ver 250 ohm, everything in between is not specified.
Might be there is voltage or noise on that particular part ?
Is it connected or is its earthing part bad ?

Also this remark in the same table :

Beeper on <20 Ω, off >250 Ω. Detects opens or shorts of 500 μs or longer.

Can this be the case ?

I told them the voltage reading above and that all connections are good with no further correspondence.

It's the beep response time is the defining of a good meter. On cheapies you can touch the probes too quick it doesn't beep...this was anecdotal anyways.

Asking a 9v battery to power a speaker over what could be 100m or more of copper can be more than a PP3 is capable of was my thinking.
I use DMMs for circuit boards and things two probe lengths away then multi function testers for loop impedance...more volts, more powah...

You can pick up noise from looped conduit and all sorts of mad things. I've seen 24VAC coming outtov an "isolated (off)" 230V receptical in a shipping container when the lights cabled in the same steel conduit were on.