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Measuring current with dmm?

borgqueenx

borgqueenx

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Dont understand how...
When the laser is turned on i put the probes on the socket connector. Also tried to switch the probes from polarity(dangerous?)
But in both cases, i got a zero on the dmm...
 





RyanElectro

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I don't know what you mean by socket connector but are you using a testload? And you're using the voltage setting right?
 
lasersbee

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borgqueenx said:
Dont understand how...
When the laser is turned on i put the probes on the socket connector. Also tried to switch the probes from polarity(dangerous?)
But in both cases, i got a zero on the dmm...
Click to expand...

You have been here long enough to know that if you
don't give detailed info and/or pictures of a problem
it is almost impossible to give any help...

Which Laser.... which PS... which DMM... which socket...
which connection points.... which...........:thinking:

Garbage in = Garbage out...


Jerry
 
C

cilegray

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To test current IE amps your multimeter need to be in parallel to your load otherwise no current will flow thru it.
Take the battery cap off. Touch one probe to the battery, the other to the bare metal threads. It will light up and give you your reading
 
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Fiddy

Fiddy

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cilegray said:
To test current IE amps your multimeter need to be in parallel to your load otherwise no current will flow thru it.
Take the battery cap off. Touch one probe to the battery, the other to the bare metal threads. It will light up and give you your reading
Click to expand...

LoL no.

For starters, a ammeter has very low resistance, so if you put it in parallel, you will be putting a direct short circuit across what ever your testing, in most cases you will blow the meter's fuse.

A ammeter goes in Series, polarity doesn't matter as it will just show a negative value in the same amplitude. make sure you've got the right source selected too i.e. AC or DC.

Fiddy.
 
lasersbee

lasersbee

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borgqueenx said:
Yes it is!
Here are images:
kroonsteen - Google zoeken
Click to expand...

Nice pictures of many types of connectors...
That helps a lot....:undecided:

Fiddy said:
cilegray said:
To test current IE amps your multimeter need to be in parallel to your load otherwise no current will flow thru it.
Take the battery cap off. Touch one probe to the battery, the other to the bare metal threads. It will light up and give you your reading
Click to expand...
LoL no.

For starters, a ammeter has very low resistance, so if you put it in parallel, you will be putting a direct short circuit across what ever your testing, in most cases you will blow the meter's fuse.

A ammeter goes in Series, polarity doesn't matter as it will just show a negative value in the same amplitude. make sure you've got the right source selected too i.e. AC or DC.

Fiddy.
Click to expand...

Exactly.... and the DMM needs to be on the right scale or
you may blow the fuse on lower ranges..

Is your DMM's battery fresh/Fully charged...:thinking:
Are your Probe wires conducting from the meter to the
probes...:thinking:


Jerry
 
Last edited:
borgqueenx

borgqueenx

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Fiddy said:
LoL no.

For starters, a ammeter has very low resistance, so if you put it in parallel, you will be putting a direct short circuit across what ever your testing, in most cases you will blow the meter's fuse.

A ammeter goes in Series, polarity doesn't matter as it will just show a negative value in the same amplitude. make sure you've got the right source selected too i.e. AC or DC.

Fiddy.
Click to expand...

I did select the correct electricity kind.
Its not operated by battery, its a laser in my laser projector.
 
Fiddy

Fiddy

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So with this knowledge did you measure the current?
 
lasersbee

lasersbee

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borgqueenx said:
I did select the correct electricity kind.
Its not operated by battery, its a laser in my laser projector.
Click to expand...

How are we supposed to know that...:thinking:

Try reading Post #3....
"A problem well stated is a problem half solved. "

Jerry
 
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borgqueenx

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Fiddy said:
So with this knowledge did you measure the current?
Click to expand...

no because like i said it doesnt work^^
for some reason my DMM keeps saying 0.
i have 2 other DMM's wich supposly failed, so i dont think the DMM is broken or something.

the DMM is set to DC, mA, and the 2 poles are in 10A and the other one is in COM.
i also tried switching from auto range to a own set value, didnt work.
i cant get a freaking reading.

EDIT: just tried reading volts. didnt work either.

EDIT2: i think its somehow broken anyway. I tried with another DMM and it could at least measure voltage. unfortunatly it cant measure high currents.
is it beyond repair? it wont measure anything.
 
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Fiddy

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you most probably have blown the meter fuse and/or your projects fuse.
 
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borgqueenx

borgqueenx

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Fiddy said:
you most probably have blown the meter fuse and/or your projects fuse.
Click to expand...

that freaking sucks. Okay il try to open it up then.

edit: i checked the fuse, and its not blown i think. still a 1 micrometer thick wire going from one end to the other.
 
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