Multimeters ref O.L

[arfurrrr]

Could you sparkies clear up a question

I`m saying O.L means open loop and a few gas guys are saying it means over loaded .

My fluke f179 , when set on ohms and not connected to anything says O.L , when i connect it i get a reading , a resistance .

Surely when its not connected to anything it wouldn`t be classed as over loaded ? would it ?

Cheers in advance .

 

[aptsys]

Overload. It makes sense for the resistance measurement as disconnected leads have a resistance too high for the meter to read.

 

[sm1thson]

if you put it on the 2v max setting (presuming it isnt auto ranging) and put 3v in it and it says OL (most likely) then there you have it!

Over range would be better terminology but theres only so much you can display with 7 segment characters.

 

[Spark123]

Out of Limit might be a better way to think of it.

 

[ban-all-sheds]

theres only so much you can display with 7 segment characters.

 

[mattylad]

Or in fact "Off load" as there is no load, no resistance, nothing connected.

"Overload" would be wrong as AFAIK that would only happen when there is something connected (a load) & its drawing too much current (over).

However "Overload = OL" is basically what fluke are saying at the start of the user guide for that meter,

To alert you to the presence of a potentially
hazardous voltage, the Y symbol is displayed when
the Meter measures a voltage ≥ 30 V or a voltage
overload (OL) condition. When making frequency
measurements >1 kHz, the Y symbol is unspecified.

Also in the display listings:

0L = The input is too large for the selected range.

Yet they later on go to show the meter with OL and an open circuit connection.

AFAIK many analogue meters were calibrated & identified as measured "off load" when zeroing the meter needle.

So it is in fact "overload" and they are using this term to indicate that, when using the resistance settings the meter has too high a resistance than it is capable of measuring & hence this "load" is "over" the current ranges = "overload".


Nice & confusing eh.

 

[aptsys]

It all comes from the fact that a multimeter is just a panel meter (volt meter) and a current to voltage converter, resistance to voltage converter and whatever else to voltage converter. As far as the display is concerned, it's just measuring a voltage so if you're trying to read something higher than the range you have it set to, it's an overload condition for the display so it displays O.L.

 

[plugwash]

Yet they later on go to show the meter with OL and an open circuit connection.

I suspect whoever designed it was thinking of the voltage and current ranges when they came up with it and then they just stuck with the same display for the over range condition in all the modes.

 

[Spark123]

I've got one of those (AVO 8 )

 

[mattylad]

I have 2

not used em for years.

 

[aptsys]

I suspect whoever designed it was thinking of the voltage and current ranges when they came up with it and then they just stuck with the same display for the over range condition in all the modes.

As I said - The display knows no difference between the ranges. It just measures a voltage for every range/setting!

 

[conny]

Whilst not intending to hi-jack this thread can someone tell me what size battery I need in the top left corner and what function it may control.
Have checked resistance and AC voltage and both work ok.

Untitled

• conny
• 16 Oct 2008
• 1

Untitled

• conny
• 16 Oct 2008
• 1

 

[Spark123]

It controls at least one of the resistance ranges on mine, should be one of these cells: clicky

 

[conny]

Thanks Spark,
it appears to control the 10k resistance range.

Cheers mate.

 

[Gasguru]

circuit diagram