Using clip on Inductive ammeter

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pcatterall

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I thought one might be useful on board and for my camper etc. So I bought a 30-0-30 version. I have tested it and it doesn't seem to work!! possibly I am doing something wrong.
Should it work on the DC side of my battery charger or on the DC lead going to my fridge ( these are the two places I have tried it so far)
Are there any tricks to using these devices? ( I know it wont be accurate)
 
pcatterall said:
I thought one might be useful on board and for my camper etc. So I bought a 30-0-30 version. I have tested it and it doesn't seem to work!! possibly I am doing something wrong.
Should it work on the DC side of my battery charger or on the DC lead going to my fridge ( these are the two places I have tried it so far)
Are there any tricks to using these devices? ( I know it wont be accurate)
Click to expand...


It should measure the current flowing in any wire it is clipped to.


Inductive ... if that is how its described, implies its an AC ammeter ( perhaps) ... but that would not be calibrated 30-0-30


Got a link to what you bought


Not clipping round a twin cable are you ?
 
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VicS said:
It should measure the current flowing in any wire it is clipped to.


....Not clipping round a twin cable are you ?
Click to expand...

Only one side of the circuit must go through it, otherwise the return current is subtracted, giving zero reading.
Or it could be broken of course!
 
It will only work on DC, not at all on AC.
The magnetic field around the cable is like a solenoid with just one turn.
It attracts or repels a magnet on the needle. Very crude but VERY useful.
As earlier, only one lead goes through it and you have to learn which way to clip it on to know which way the current is flowing. It's usually obvious, battery charger vs service loads.
Don't clp it on the starter cable, you might bend the needle!!
 
As mentioned, it will only work when clamped around a single conductor. Post above is incorrect, many cheap ones only display AC via the clamp but better models will handle both AC & DC. Ones capable of handling DC used to be fairly rare and expensive but nowadays they are very common. Still worth reading the spec. to make certain it will work with DC.

Unless it is broken then yours isn't workng because:
a) You aren't clamping it around just one wire
b) It isn't capable of displaying DC Amps.
c) You have chosen the wrong setting
d) Any combination of a & c

Example of spec. you don't want (form eBay)
Digital clamp ammeter
Meter Measures AC and DC Voltage
Diode Test
LCD Display
AC Current 0.1A - 1000A
AC Voltage 1V - 750V
DC Voltage 1V - 1000V

Note: DC current range not quoted so this model only works as an AC clamp ammeter. I've heard people complaining that their newly purchased meter doesn't work and it was because they'd just assumed it would measure AC & DC Amps.
 
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Hmmmm. thanks all. Not ebay and stated as DC. test on fridge was both wires.... point taken on that!! test on charger was just one lead though. I will test it my car head lamp or something that should give a decent reading.
Thanks
 
My answer is correct for a crude old fashioned clip-on ammeter. Looks like a round meter with a spring lip on the back.

If you a talking of an electronic clamp meter then I am incorrect. Has a loop that opens to feed the wire through and then closed.

Which is it?
 
Chalker said:
My answer is correct for a crude old fashioned clip-on ammeter. Looks like a round meter with a spring lip on the back.

If you a talking of an electronic clamp meter then I am incorrect. Has a loop that opens to feed the wire through and then closed.

Which is it?
Click to expand...

Similar to this (except that this one is designed for permanent installation in a motor car and has a fixed loop).

DSCF1173.jpg



DSCF1175.jpg
 
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Chalker said:
My answer is correct for a crude old fashioned clip-on ammeter. Looks like a round meter with a spring lip on the back.

If you a talking of an electronic clamp meter then I am incorrect. Has a loop that opens to feed the wire through and then closed.

Which is it?
Click to expand...

Apologies, yes I actually remember seeing these a long time ago. I'd forgotten and assumed OP meant a modern clamp ammeter (I've seen those described as inductive ammeters as well even though they are a completely different beast. The 30-0-30 is a giveaway that it is the old style. I didn't even know they were still for sale. Tend to think that things I saw as a lad have probably gone the way the dodo went. :D

In defence, I'd spoken to someone recently who'd bought a cheapo clamp meter and found it didn't measure DC current. So subject was fresh in my memory.
 
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