Maxim Integrated 71M6541 Demo Board - Manual (Page 55)

71M6541 Demo Board REV 3.0 User’s Manual
55 Rev 4.0
2.6.3 PLACEMENT OF SENSORS (IEC)
The arrangement of the current terminals in a typical IEC meter enclosure predetermines the spacing of the
shunts, and usually allows for only for 20 to 22 mm center-to-center spacing between the shunts. This means
that the clearance between adjacent shunts is typically only 10 mm or less. A typical arrangement is shown in
Figure 2-15, left side. This arrangement is not optimized for suppression of cross-talk.
In order to minimize cross-talk between phases, the shunts should be turned by 90 degrees as shown in Figure
2-15, right side. In this arrangement, the sensitive areas of the shunts are kept away from the adjacent currents.
Figure 2-15: Typical Sensor Arrangement (left), Recommended Arrangement (right)
Other arrangements are shown in Figure 2-16. In the left figure, the shunts are shown swiveled by 90 degrees
towards the terminals. In the right figure, the shunts are shown staggered in height, for example by using spac-
ers.
It is useful to minimize the loop area formed by the Manganin zone of the shunts and the wires. As with the AN-
SI sensors, it is recommended that sensor wires are tightly twisted to avoid loops that can be penetrated by the
magnetic fields of the sensors or conductors.
Figure 2-16: Improved Sensor Arrangement