| The 'measured' amps is then multipled up by passing the lead through multiple times.
One of the first observations is the B side is linear upto and including the 13 passes (84amps) but the A side gets saturated at about 60amps.
I not sure if this is just manufacturing variation or a 'bad' sensor - to my mind it is well outside manufacturing tollerances.
A table was then made for the measured values and I used Excel to goal seek the best fit number for the scale factor and then calculated the offset last.
I also found the EIS can take 'big' offset and factor numbers, if you multiple up the SF / SO by 10 decimal values can then be used. My test results are below:
Turns AMP A Volts Book A Cal A B Volts Book B Cal B
0 0 2.39 -1 0.4 2.39 0 0.4
1 6.4 2.62 17 6.8 2.49 7 6.8
2 12.8 2.85 34 13.3 2.59 15 13.2
3 19.2 3.08 51 19.7 2.69 22 19.6
4 25.6 3.32 69 26.1 2.79 30 26.0
5 32 3.55 86 32.5 2.89 37 32.6
6 38.4 3.80 105 39.4 2.99 45 38.9
7 44.8 4.02 121 45.4 3.09 52 45.5
8 51.2 4.23 137 51.2 3.19 59 51.6
9 57.6 4.49 156 58.4 3.29 67 58.0
10 64 4.72 173 64.7 3.39 74 64.3
11 70.4 4.74 175 65.2 3.49 81 70.6
12 76.8 4.74 175 65.2 3.59 89 77.2
13 83.2 4.74 175 65.2 3.69 97 83.7
Factor 186 688 186 1602
EIS Offset 357 1305 357 3057
Offset -179 -652 -179 -1528
For reference the equation is: Result = (Value * ScaleFactor / 2.5) + ScaleOffset
So we have 'an option' but the A side is still a concern. | 
