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Posted to uk.d-i-y
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Making a Shunt Resistor
On 12/01/13 23:40, wrote:
On Friday, January 4, 2013 9:53:47 PM UTC, alan wrote:
On 04/01/2013 08:43, harry wrote:
Of course current flows in the voltmeter, how else could it work?
The better the quality of the instrument, the lower current it needs
for full scale deflection, hence the less effect it has on the circuit
measured.
Even a 4 quid multimeter will have an input impedance in the mega Ohm
range. The inaccuracies due the the meter impedance and measurement
leads is vanishingly small and completely swamped by the specified
accuracy of the shunt resistor and voltmeter.
Analogue meters are much lower R than that. Good ones are usually 50k/V, cheapies more like 1/10th that.
NT
Ive yet to see one much less than 20kohm/V
--
Ineptocracy
(in-ep-toc-ra-cy) €“ a system of government where the least capable to
lead are elected by the least capable of producing, and where the
members of society least likely to sustain themselves or succeed, are
rewarded with goods and services paid for by the confiscated wealth of a
diminishing number of producers.
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