[time-nuts] Slightly OT: inexpensive USB analog-digital converter?

[Poul-Henning Kamp]

In message <47911B8F.5050100 at xtra.co.nz>, Bruce Griffiths writes:
>Poul-Henning Kamp wrote:
>> If you hook it to a Hall based current-sensor like the LEM LTSR, then
>> there is no problem with it.
>>   
>If a 0.7% accuracy and 6At range suffices.
>
>A feedback hall sensor has better linearity, however they have a
>relatively large offset drift.

They ARE feedback halls :-)

Their specs are pretty hard to read however.

The 6A is the "nominal range", but the "measurement range" is three
times larger (limited by the output voltage).

They have other models with larger nominal current and correspondingly
higher range.

The measurement errors are static and can be calibrated out, the
major one I found is stray magnetic fields.

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