DC Ground Point
The CP should be connected to the GP as shown in Figures 40 through 43 (unless one load is already grounded), making certain there is only one conductive path between these two points. This connection should be such that the total impedance from the DC Common for example, be the separate ground terminal located on one of the power supplies or loads in a system, or it may be a special system ground terminal, bus, or plane established expressly for ground connection purposes.
The CP should be connected to the GP as shown in Figure 40 through 43 (unless one load is already grounded), making certain there is only one conductive path between these two points. This connection should be such that the total impedance from the DC Common Point to the DC Ground Point is not large compared with the impedance from the GP to earth ground. Braided leads are sometimes used to further reduce the high frequency component of this ground load impedance.
Sometimes the impedance between the CP and the GP is minimized by using a single terminal or bar for both. In these cases, care should be taken that all DC System connections are made at one end of the terminal or bar, and any Ground System connection at the other, so that the DC and Ground System currents are not intertwined.
When checking for unintentional paths from dc to ground, be sure that any straps or wires between power supply output and ground terminals have been removed (unless, of course, this is the single desired connection between the CP and the GP).
Remote Error Sensing (Constant Voltage Operation Only)
Normally, a power supply achieves its optimum load and line regulation, its lowest output impedance, drift, ripple and noise, and its fastest transient recovery performance at the power supply output terminals (Figure 46).
Figure 46. Regulated Power Supply with Local (Normal) Error Sensing
If the load is separated from the output terminals by any lead length, some of these performance characteristics will be degraded at the load
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