Winston wrote:

In that case, you can simplify the arithmetic with:
ACS758ECB-200B-PSS-T (Straight Leads) OR
ACS758ECB-200B-PFF-T (Bent Leads)

With your DMM negative lead connected to
the center of a stiff, precision 2:1 voltage
divider and it's positive lead to pin 3 of
the chip, You just multiply the output by 100
to get your reading:

+2.000 V = 200.0 A
+0.153 V = 15.3 A
0 V = 0.0 A
-2.000 V = -200.0 A

Seven smackers each.

http://search.digikey.com/scripts/DkSearch/dksus.dll?lang=en&site=US&WT.z_homepage_link=hp_go _button&KeyWords=ACS758ECB-200B&x=0&y=0

Even better, thanks Winston.

Jon