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mobman
01-08-2009, 01:35 PM
i just wanted to make sure I ask you guys before I install my new ammeter.

it has a positive and a negative terminal coming out of the back. Where exactly do I connect these two to be able to get an accurate reading about how much amps my HHO system draws?

H2OPWR
01-08-2009, 01:50 PM
i just wanted to make sure I ask you guys before I install my new ammeter.

it has a positive and a negative terminal coming out of the back. Where exactly do I connect these two to be able to get an accurate reading about how much amps my HHO system draws?

Most amp meters connect in line with only the positive lead. If you have a light in your amp meter that could be what the negative lead is all about. The other possibility is that your amp meter requires an external shunt.

Q-Hack!
01-08-2009, 01:58 PM
You need to connect it in series like this:


(+)-------(+)Ammeter(-)------(+)
Battery......................HHO
(-)--------------------------(-)

Ignore the periods above... they are just to make it format correctly.

Also, you can use the ammeter on the negative side of the circuit, just make sure to reverse the ammeter. The idea being that the positive lead of the ammeter needs to be on the more positive side of the circuit. ie. closer to the positive battery terminal than the negative lead.


(+)--------------------------(+)
Battery......................HHO
(-)-------(-)Ammeter(+)------(-)

mobman
01-08-2009, 02:04 PM
You need to connect it in series like this:


(+)-------(+)Ammeter(-)------(+)
Battery......................HHO
(-)--------------------------(-)

Ignore the periods above... they are just to make it format correctly.

Also, you can use the ammeter on the negative side of the circuit, just make sure to reverse the ammeter. The idea being that the positive lead of the ammeter needs to be on the more positive side of the circuit. ie. closer to the positive battery terminal than the negative lead.


(+)--------------------------(+)
Battery......................HHO
(-)-------(-)Ammeter(+)------(-)



Great explanation Q-Hack...I think I get it thank you! ;)

Q-Hack!
01-08-2009, 02:12 PM
The other possibility is that your amp meter requires an external shunt.

Many times you'll see an ammeter that has a built in current sense resistor. These are effectively a shunt but in a smaller package. This type of ammeter will have a + and - labled on the meter. Usually, if you bought the ammeter new and it requires a shunt, it will come with it. All bets are off if you bought it second hand.

The good news is that there is a real easy test for this... If you hook it up and it lets the magic smoke out... you now know that you needed a shunt. :D and a new meter

mobman
01-09-2009, 09:39 AM
Many times you'll see an ammeter that has a built in current sense resistor. These are effectively a shunt but in a smaller package. This type of ammeter will have a + and - labled on the meter. Usually, if you bought the ammeter new and it requires a shunt, it will come with it. All bets are off if you bought it second hand.

The good news is that there is a real easy test for this... If you hook it up and it lets the magic smoke out... you now know that you needed a shunt. :D and a new meter

I dont really know what a shunt is, but my ammeter does come with a + and - labelled at the back.