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to check the output of your alternator just connect the ammeter across the battery and set it to 20 v dc it should read 12v at tickover and rise to around 14v at 3k revs
to check the output of your alternator just connect the ammeter across the battery and set it to 20 v dc it should read 12v at tickover and rise to around 14v at 3k revs
Ammeters read in "Amps", hence the name, and measure current drawn NOT Potential difference (Volts).
An ammeter must be in line with the circuit rather than across it as the first poster said although I don't know the conections on a Subaru alternator, most cars will have a lead to the battery and starter, and one for the charge light.
The meter will need to go inline with the battery lead somewhere.
If your wanting to measure the output current you need to use the wire that goes to the bolt on the alternator, the plug in the alternator just has the warning light and sense wires going to it.