How do I read this amp meter

[Monacoach]

Trying to measure my chassis battery parasitic drain with this digital amp meter. I removed the negative battery cable and joined the cable to the batt post with the amp meter. Set it to the 10 amp position........the reading is - 2.5
What does this negative number mean?

[Skip426]

What brand and model of amp meter . Do you have the users manual?

[sdennislee]

Negative could be due to reversed leads on the meter. If the meter has red and black leads reverse the position of the leads. To see a simple example of this test a battery, red lead to positive, black lead to negative, note the meter reading, then switch the leads to, red to negative and black to positive you will see the reading go from positive to negative

[Ranger Smith]

reverse the leads

[the trainguy]

Originally Posted by Ranger Smith

reverse the leads

That's it!
Just be careful not to exceed the amp rating of your meter cause you can burn it up.
Most digital meters are good for 10 amps when reading current.

Bob

[Monacoach]

Its a mastercraft 052-0060-2 most likely came with a user manual but it should also have come with a reminder to the user to not lose the manual.
As far as reversing the leads would it make a difference seeing as i am going from negative terminal to negative cable not positive to negative?

[sdennislee]

Can you upload a picture or diagram of your set up?

[the trainguy]

It really doesn't matter if it reads positive or negative.
You have it set to "amps" making sure that the leads are plugged into the proper jacks on the meter.
One meter lead on the negative battery post and the other lead on the lifted negative battery cable.
You will be reading the dc current going through the meter.
Make sure it's set to "DC Current" on the dial or pushbuttons.
Just be careful not to exceed the meters current rating.

Bob

[dpinvidic]

2.5 amps is 2.5 amps, there is a direction to current flow, and the meter is just showing you the direction of the current...which is not important here.

If you turned on your charger, AND the charge current was less than 10 amps, the neg. sign would go away.


Be careful when measuring current. Many items have a higher "inrush" current, which can be higher than 10 amps. Your meter likely has a fuse inside....and maybe two fuses. The higher inrush current can blow the internal fuse.

For these cases, I disconnect the battery cable, then use a regular jumper wire connected to both probes. Then attach your probes to the circuit. The inrush goes through the jumper. When ready to measure, remove the jumper and the meter will show the current.

Regards,
Dan

[Old Radios]

Originally Posted by sdennislee

Negative could be due to reversed leads on the meter. If the meter has red and black leads reverse the position of the leads. To see a simple example of this test a battery, red lead to positive, black lead to negative, note the meter reading, then switch the leads to, red to negative and black to positive you will see the reading go from positive to negative

Holy Crap!!!! NO NO NO !!!
Don't test a car or house battery by putting the meter in amps and touching each test lead to the positive and negative terminals of the battery. That can create a dead short across the battery. At the least sparks could fly and you will blow a fuse in your meter. A lot worse could happen especially if it's a cheap meter.

[sdennislee]

Originally Posted by Old Radios

Holy Crap!!!! NO NO NO !!!
Don't test a car or house battery by putting the meter in amps and touching each test lead to the positive and negative terminals of the battery. That can create a dead short across the battery. At the least sparks could fly and you will blow a fuse in your meter. A lot worse could happen especially if it's a cheap meter.

Should have been clear, I meant to test something like a AA battery.

[TQ60]

First learn one strong habit.

NEVER leave the leads plugged in while in amps mode.

ALWAYS move the wire back to volts when finished.

The ammeter position is just a wire so leaving it as ammeter then checking a voltage later would have the voltmeter short out whatever you are working on.

Next, RED always goes toward positive.

If you disconnect the ground on the battery the battery negative post is more positive than the chassis.

Next, most vehicles have filter capacitors and possible high current items that may do a self test, so first connection causes a spark that can blow the internal fuse in the meter.

WHAT TO DO?

Get a couple clip leads to make your connections because you need more hands than 2.

Loosen the bolt for the ground wire.

Lift wire then count to 10 then touch back and observe spark.

Now disconnect and set aside and reconnect to battery with a clip lead.

Set ammeter to highest range usually 10 amps and use correct holes in meter..

Connect black to chassis and red to negative post.

Remove clip lead connecting ground to battery and read amps.

Adjust range downward until good reading.

If less than 2 amps and changing to 2 amps requires using different hole in meter reconnect ground clip lead then move lead at meter.

This process is more work but avoids needing to try to find that stupid fuse that nobody sells!

[Monacoach]

First no I cant post pics that would take a whole new thread
Second.. I guess I ignore the negative sign and assume that I have a 2.5 amp drain from the chassis. Seems high right?

[sdennislee]

Correct, ignore the negative symbol