Re: Multimeter?

In article <20081210134510.43e53c3e@xxxxxxxxxxxxxxxxx>,
Alex Buell <alex.buell@xxxxxxxxxxxxx> wrote:
On Thu, 4 Dec 2008 00:12:29 -0000, I waved a wand and this message
magically appears in front of Mark:

http://www.maplin.co.uk/Module.aspx?ModuleNo=37279

That one arrived early this morning and I've just used it. Appears when
the engine is running it's measuring 14.49v. Which is good news. With
the engine off, voltage is about 13.08v. Is that normal?

The battery off charge volts will be higher than actual if you measure
then just after stopping the engine. Best to wait a while.

What's not so good is that I appear not to be able to measure how much
current is being drawn when switched off (i.e to see if its the car
alarm or the radio). How can I do that?

The meter needs to be switched to current - use the 10 amp range - and the
red lead moved to the 10 amp socket. Then disconnect one battery lead and
insert the meter between that lead and battery terminal. So they are wired
in series. If you get a minus reading swap the meter connections round.

If you previously were measuring voltage and simply switched to read
current on the low current range with the meter still connected you've
probably blown an internal fuse in it. Exactly as was pointed out earlier
in this thread.

--
*If you can't see my mirrors, I'm doing my hair*

Dave Plowman dave@xxxxxxxxxxxxxxx London SW
To e-mail, change noise into sound.
.

Relevant Pages

  • Re: Electronic keyboard repair (I hope)
    ... That board (or portion of the main circuit board where the ... DC adapter connects) is where the excess voltage is regulated down to a ... To what extent will such an accurate measuring device empty my po' wallet? ... which is why you need a meter that can read ...
    (sci.electronics.repair)
  • Re: Frequency Measurement with a DMM
    ... > In the Measuring Frequency section of the user's manual, ... you might damage your meter and expose yourself to ... It could damage the ... > limit voltage: AC 20 V max." in Item B? ...
    (sci.electronics.basics)
  • Re: Measuring the resistance of a hot resistor
    ... also need a meter for measuring current and another for measuring ... It is certainly easier to get an accurate current and voltage meter ... than it is an accurate ohm meter. ...
    (sci.electronics.basics)
  • Re: Measuring mA (debate solution needed)
    ... He's calculating the current in a circuit my measuring the voltage ... read the meter. ...
    (sci.electronics.design)
  • Re: 259 miles into addiction and the damn thing wont charge :(
    ... FJ-600 engine in a smaller chassis. ... The transistor would be ON or OFF, according to the voltage coming out ... electromagnet. ... As the rotor turns, the electromagnetic field turns and it induces ...
    (rec.motorcycles.tech)