The device gain variant chosen, A1, A2, or A3 directly affects the feasible device placement locations. Figure 6-3 and Figure 6-4 aim to provide some intuition on the benefits of when to use each device variant.

In Figure 6-3 the device spacing is fixed at 9.5 mm from the center of the bus bar which represents the devices being aligned with the outer edges of the bus bar. The full-scale range was set at 1200A. The distance from the bus bar to sensor PCB was swept and the results shown for each device gain variant.

For the given configuration the A1 device gain variant is only feasible for a PCB distance up to 3 mm. The A2 variant is feasible up to 10 mm and the A3 variant up to 16 mm. Beyond these distances the sensors do not have enough gain to scale the magnetic field to meet the full-scale range specified.

Figure 6-3 Error vs Distance from PCB (different device gains)

Figure 6-4 shows the error vs device spacing for a fixed bus bar to sensor PCB distance of 4 mm. Once again A1 has the most limited range of device spacing whereas the A2 and A3 devices show reasonable error across the whole device spacing range tested.

Figure 6-4 Error vs Device Spacing (different device gains)