On 2005-03-02 d02mgt$hj8$ firstname.lastname@example.org said:
> email@example.com wrote:
>> > ... The really cheap meters will say something like 2 Kohm /
>> >volt or 3 K ohm /
volt on the face. A better quality one will
>>say >something like 20K ohm / volt. These ratings are usually
>>based on 1 >milliamp giving full scale deflection of the
>> No, not 1 mA.
>> 2 Kohm/volt = .5 mA
>> 3 Kohm/volt = .33 mA
>> 20 Kohm/volt = 50 microAmps
>You forget that there are different scales on the meter face.
No I didn't. Unless my simple, ohm's law calculations were wrong, meter
movement sensitivity is 1 / ohms per volt. To set measuring range of
meter you select a multiplier resistor which supplies full scale meter
current at your desired full scale voltage.
A 1Kohms/volt meter would use 10K to read 10V full scale.
A 20Kohms/volt would need 200K for the same range.
>scale deflection on one scale may be reading 250 volts and 10 volts
>on another. The meter movement HAS to see the same amperage in
>order to get fullscale deflection. The amount of resistance you
>have to add will, of course, vary with each scale,
>but at no time
>can the current EXCEED the 1 ma (or whatever) at full
Huh? Sorry, not clear to me what your point is here.
>please, shoot me now...
Naw - you're doing OK now.
Tom Willmon near Mountainair, (mid) New Mexico, USA
Net-Tamer V 1.12.0 - Registered