Notes on current measurements using Hall sensors

The device described in this documentation features one or several integrated Hall sensor for the purpose of current measurements.

During this process, the Hall sensor monitors the magnetic field generated by a current flowing through a conductor.

In order to prevent compromising the measurement we recommend screening exterior magnetic fields from the device, or to keep such fields at an adequate distance.

Background

A current-carrying conductor generates a magnetic field around it according to

B = µ₀ * I / (2π * d)

with

B [Tesla]    magnetic field

µ0 = 4*π*10^-7 [H/m] (assumption: no magnetic shielding)

I [A]    current

d [m]    distance to conductor

Interference from external magnetic fields The magnetic field strength should not exceed a permitted level all around the device. In practice this equates to a recommended minimum distance between a conductor and the device surface as follows: - Current 10 A: 12 mm - Current 20 A: 25 mm - Current 40 A: 50 mm Unless specified otherwise in the device documentation, stringing together modules (e.g. terminal blocks based on a 12 mm grid) of same type (e.g. EL2212-0000) is permitted.