alternator output

[Richard007]

Hi All

I have recently fitted a alternator to my MM and was wondering what I voltage output should be mine is giving me 12.5V on tick over then goes to 14.5v which is just in the high reading with my tester is this OK or should I be looking at a regulator.
Thanks

[mogbob]

Richard
The voltage figures look fine to me , i.e revving the engine produces 14.5 Volts. Once your battery has been "fully charged " , after a decent run , then you would expect the figure to settle down to a normal 12.6 volts ( fully charged battery ).

If you only use your car for short journeys then the battery will always be calling on the Alternator to produce more charge
i.e.more volts. With this cold weather upon us , demand on the battery is now in it's busy season , until the spring 2017.

Not sure I understand your reference to " looking at a regulator " . The Alternator incorporates it's own regulator. If it continues to pump out 14.5 volts after a long run ,it's probably an indication that the battery is getting near it's sell by date
and not holding it's charge.

Sounds to me that everything is OK so just enjoy some safe motoring but don't hesitate to clarify anything you're not sure of.
Welcome to the Forum.
Bob

[Richard007]

Thanks for that

[oliver90owner]

The alternator output voltage is generally regulated at around 14.3-14.4V. The current supplied will be adjusred by the regularor to maintain that output voltage, irrespective of age of battery, right up to the full output of the alternator. You would recognise a discharged or aged battery by cranking voltage drop. Not all testers are particularly accurate. DMMs are accurate to about 2% of full scale (as long as the DMM battery is OK.), but most are better than this standard.